From fe185e5b8dd988df8f952c2a2106a8fd148e436b Mon Sep 17 00:00:00 2001
From: Alex <a@tushynski.me>
Date: Sat, 28 Mar 2026 21:51:47 +0000
Subject: [PATCH] chore: api and tool tests

---
 tests/agents/test_api_body_serializer.py      | 202 +++++++
 tests/agents/test_api_tool.py                 | 282 ++++++++++
 tests/agents/test_brave_tool.py               | 132 +++++
 tests/agents/test_cryptoprice_tool.py         |  85 +++
 tests/agents/test_duckduckgo_tool.py          | 145 +++++
 tests/agents/test_mcp_tool.py                 | 519 ++++++++++++++++++
 tests/agents/test_ntfy_tool.py                | 146 +++++
 tests/agents/test_postgres_tool.py            | 146 +++++
 tests/agents/test_read_webpage_tool.py        |  86 +++
 tests/agents/test_spec_parser.py              | 335 +++++++++++
 tests/agents/test_telegram_tool.py            |  79 +++
 tests/api/answer/routes/test_answer.py        | 235 ++++++++
 tests/api/answer/routes/test_stream.py        | 195 +++++++
 .../answer/services/compression/__init__.py   |   0
 .../compression/test_message_builder.py       | 303 ++++++++++
 .../services/compression/test_orchestrator.py | 447 +++++++++++++++
 .../services/compression/test_service.py      | 423 ++++++++++++++
 .../answer/services/compression/test_types.py | 131 +++++
 18 files changed, 3891 insertions(+)
 create mode 100644 tests/agents/test_api_body_serializer.py
 create mode 100644 tests/agents/test_api_tool.py
 create mode 100644 tests/agents/test_brave_tool.py
 create mode 100644 tests/agents/test_cryptoprice_tool.py
 create mode 100644 tests/agents/test_duckduckgo_tool.py
 create mode 100644 tests/agents/test_mcp_tool.py
 create mode 100644 tests/agents/test_ntfy_tool.py
 create mode 100644 tests/agents/test_postgres_tool.py
 create mode 100644 tests/agents/test_read_webpage_tool.py
 create mode 100644 tests/agents/test_spec_parser.py
 create mode 100644 tests/agents/test_telegram_tool.py
 create mode 100644 tests/api/answer/routes/test_answer.py
 create mode 100644 tests/api/answer/routes/test_stream.py
 create mode 100644 tests/api/answer/services/compression/__init__.py
 create mode 100644 tests/api/answer/services/compression/test_message_builder.py
 create mode 100644 tests/api/answer/services/compression/test_orchestrator.py
 create mode 100644 tests/api/answer/services/compression/test_service.py
 create mode 100644 tests/api/answer/services/compression/test_types.py

diff --git a/tests/agents/test_api_body_serializer.py b/tests/agents/test_api_body_serializer.py
new file mode 100644
index 00000000..b10d0429
--- /dev/null
+++ b/tests/agents/test_api_body_serializer.py
@@ -0,0 +1,202 @@
+"""Tests for application/agents/tools/api_body_serializer.py"""
+
+import json
+
+import pytest
+
+from application.agents.tools.api_body_serializer import (
+    ContentType,
+    RequestBodySerializer,
+)
+
+
+@pytest.mark.unit
+class TestContentTypeEnum:
+    def test_json_value(self):
+        assert ContentType.JSON == "application/json"
+
+    def test_form_urlencoded_value(self):
+        assert ContentType.FORM_URLENCODED == "application/x-www-form-urlencoded"
+
+    def test_multipart_value(self):
+        assert ContentType.MULTIPART_FORM_DATA == "multipart/form-data"
+
+    def test_text_plain_value(self):
+        assert ContentType.TEXT_PLAIN == "text/plain"
+
+    def test_xml_value(self):
+        assert ContentType.XML == "application/xml"
+
+    def test_octet_stream_value(self):
+        assert ContentType.OCTET_STREAM == "application/octet-stream"
+
+
+@pytest.mark.unit
+class TestSerializeJson:
+    def test_basic_json(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"key": "value"}, ContentType.JSON
+        )
+        assert json.loads(body) == {"key": "value"}
+        assert headers["Content-Type"] == "application/json"
+
+    def test_nested_json(self):
+        data = {"user": {"name": "Alice", "age": 30}}
+        body, headers = RequestBodySerializer.serialize(data, ContentType.JSON)
+        assert json.loads(body) == data
+
+    def test_empty_body_returns_none(self):
+        body, headers = RequestBodySerializer.serialize({}, ContentType.JSON)
+        assert body is None
+        assert headers == {}
+
+    def test_none_body(self):
+        body, headers = RequestBodySerializer.serialize(None, ContentType.JSON)
+        assert body is None
+
+    def test_unknown_content_type_falls_back_to_json(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"k": "v"}, "application/vnd.custom+json"
+        )
+        assert json.loads(body) == {"k": "v"}
+
+    def test_content_type_with_charset_suffix(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"k": "v"}, "application/json; charset=utf-8"
+        )
+        assert json.loads(body) == {"k": "v"}
+
+
+@pytest.mark.unit
+class TestSerializeFormUrlencoded:
+    def test_basic_form(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"name": "Alice", "age": "30"}, ContentType.FORM_URLENCODED
+        )
+        assert "name=Alice" in body
+        assert "age=30" in body
+        assert headers["Content-Type"] == "application/x-www-form-urlencoded"
+
+    def test_none_values_skipped(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"name": "Alice", "skip": None}, ContentType.FORM_URLENCODED
+        )
+        assert "name=Alice" in body
+        assert "skip" not in body
+
+    def test_list_explode_true(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"tags": ["a", "b"]},
+            ContentType.FORM_URLENCODED,
+            encoding_rules={"tags": {"style": "form", "explode": True}},
+        )
+        assert "tags=a" in body
+        assert "tags=b" in body
+
+    def test_list_explode_false(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"tags": ["a", "b"]},
+            ContentType.FORM_URLENCODED,
+            encoding_rules={"tags": {"style": "form", "explode": False}},
+        )
+        # Value is percent-encoded by _serialize_form_value then urlencoded again
+        assert "tags=" in body
+        assert "a" in body and "b" in body
+
+    def test_dict_value_json_content_type(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"metadata": {"key": "val"}},
+            ContentType.FORM_URLENCODED,
+            encoding_rules={"metadata": {"contentType": "application/json"}},
+        )
+        assert "metadata" in body
+
+
+@pytest.mark.unit
+class TestSerializeTextPlain:
+    def test_single_value(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"message": "hello"}, ContentType.TEXT_PLAIN
+        )
+        assert body == "hello"
+        assert headers["Content-Type"] == "text/plain"
+
+    def test_multiple_values(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"name": "Alice", "age": 30}, ContentType.TEXT_PLAIN
+        )
+        assert "name: Alice" in body
+        assert "age: 30" in body
+
+
+@pytest.mark.unit
+class TestSerializeXml:
+    def test_basic_xml(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"name": "Alice"}, ContentType.XML
+        )
+        assert '<?xml version="1.0"' in body
+        assert "<name>Alice</name>" in body
+        assert headers["Content-Type"] == "application/xml"
+
+    def test_nested_xml(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"user": {"name": "Alice"}}, ContentType.XML
+        )
+        assert "<user>" in body
+        assert "<name>Alice</name>" in body
+
+    def test_xml_escapes_special_chars(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"data": "<script>alert('xss')</script>"}, ContentType.XML
+        )
+        assert "&lt;script&gt;" in body
+
+
+@pytest.mark.unit
+class TestSerializeOctetStream:
+    def test_dict_body(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"key": "val"}, ContentType.OCTET_STREAM
+        )
+        assert isinstance(body, bytes)
+        assert headers["Content-Type"] == "application/octet-stream"
+
+
+@pytest.mark.unit
+class TestSerializeMultipartFormData:
+    def test_basic_multipart(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"field": "value"}, ContentType.MULTIPART_FORM_DATA
+        )
+        assert isinstance(body, bytes)
+        assert "multipart/form-data" in headers["Content-Type"]
+        assert "boundary=" in headers["Content-Type"]
+
+    def test_none_values_skipped(self):
+        body, headers = RequestBodySerializer.serialize(
+            {"field": "value", "empty": None}, ContentType.MULTIPART_FORM_DATA
+        )
+        body_str = body.decode("utf-8", errors="replace")
+        assert "field" in body_str
+        assert "empty" not in body_str
+
+
+@pytest.mark.unit
+class TestHelpers:
+    def test_percent_encode(self):
+        assert RequestBodySerializer._percent_encode("hello world") == "hello%20world"
+        assert RequestBodySerializer._percent_encode("a/b") == "a%2Fb"
+        assert RequestBodySerializer._percent_encode("safe", safe_chars="/") == "safe"
+
+    def test_escape_xml(self):
+        assert "&amp;" in RequestBodySerializer._escape_xml("&")
+        assert "&lt;" in RequestBodySerializer._escape_xml("<")
+        assert "&gt;" in RequestBodySerializer._escape_xml(">")
+        assert "&quot;" in RequestBodySerializer._escape_xml('"')
+        assert "&apos;" in RequestBodySerializer._escape_xml("'")
+
+    def test_dict_to_xml_list(self):
+        xml = RequestBodySerializer._dict_to_xml({"items": [1, 2, 3]})
+        assert "<item>1</item>" in xml
+        assert "<item>2</item>" in xml
diff --git a/tests/agents/test_api_tool.py b/tests/agents/test_api_tool.py
new file mode 100644
index 00000000..8f59c225
--- /dev/null
+++ b/tests/agents/test_api_tool.py
@@ -0,0 +1,282 @@
+"""Tests for application/agents/tools/api_tool.py"""
+
+import json
+from unittest.mock import MagicMock, patch
+
+import pytest
+import requests
+
+from application.agents.tools.api_tool import APITool
+
+
+@pytest.fixture
+def tool():
+    return APITool(
+        config={
+            "url": "https://api.example.com/data",
+            "method": "GET",
+            "headers": {"Accept": "application/json"},
+            "query_params": {},
+        }
+    )
+
+
+@pytest.fixture
+def post_tool():
+    return APITool(
+        config={
+            "url": "https://api.example.com/items",
+            "method": "POST",
+            "headers": {},
+            "query_params": {},
+        }
+    )
+
+
+@pytest.mark.unit
+class TestAPIToolInit:
+    def test_default_values(self):
+        tool = APITool(config={})
+        assert tool.url == ""
+        assert tool.method == "GET"
+        assert tool.headers == {}
+        assert tool.query_params == {}
+
+
+@pytest.mark.unit
+class TestMakeApiCall:
+    @patch("application.agents.tools.api_tool.validate_url")
+    @patch("application.agents.tools.api_tool.requests.get")
+    def test_successful_get(self, mock_get, mock_validate, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.headers = {"Content-Type": "application/json"}
+        mock_resp.json.return_value = {"result": "ok"}
+        mock_resp.content = b'{"result":"ok"}'
+        mock_get.return_value = mock_resp
+
+        result = tool.execute_action("any_action")
+
+        assert result["status_code"] == 200
+        assert result["data"] == {"result": "ok"}
+        assert result["message"] == "API call successful."
+
+    @patch("application.agents.tools.api_tool.validate_url")
+    @patch("application.agents.tools.api_tool.requests.post")
+    def test_successful_post(self, mock_post, mock_validate, post_tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 201
+        mock_resp.headers = {"Content-Type": "application/json"}
+        mock_resp.json.return_value = {"id": 1}
+        mock_resp.content = b'{"id":1}'
+        mock_post.return_value = mock_resp
+
+        result = post_tool.execute_action("create", name="test")
+
+        assert result["status_code"] == 201
+
+    @patch("application.agents.tools.api_tool.validate_url")
+    def test_ssrf_blocked(self, mock_validate, tool):
+        from application.core.url_validation import SSRFError
+
+        mock_validate.side_effect = SSRFError("blocked")
+
+        result = tool.execute_action("any")
+
+        assert result["status_code"] is None
+        assert "URL validation error" in result["message"]
+
+    @patch("application.agents.tools.api_tool.validate_url")
+    @patch("application.agents.tools.api_tool.requests.get")
+    def test_timeout_error(self, mock_get, mock_validate, tool):
+        mock_get.side_effect = requests.exceptions.Timeout()
+
+        result = tool.execute_action("any")
+
+        assert result["status_code"] is None
+        assert "timeout" in result["message"].lower()
+
+    @patch("application.agents.tools.api_tool.validate_url")
+    @patch("application.agents.tools.api_tool.requests.get")
+    def test_connection_error(self, mock_get, mock_validate, tool):
+        mock_get.side_effect = requests.exceptions.ConnectionError("refused")
+
+        result = tool.execute_action("any")
+
+        assert result["status_code"] is None
+        assert "Connection error" in result["message"]
+
+    @patch("application.agents.tools.api_tool.validate_url")
+    @patch("application.agents.tools.api_tool.requests.get")
+    def test_http_error(self, mock_get, mock_validate, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 404
+        mock_resp.text = "Not Found"
+        mock_resp.json.side_effect = json.JSONDecodeError("", "", 0)
+        mock_resp.raise_for_status.side_effect = requests.exceptions.HTTPError(
+            response=mock_resp
+        )
+        mock_get.return_value = mock_resp
+
+        result = tool.execute_action("any")
+
+        assert result["status_code"] == 404
+        assert "HTTP Error" in result["message"]
+
+    @patch("application.agents.tools.api_tool.validate_url")
+    def test_unsupported_method(self, mock_validate):
+        tool = APITool(
+            config={"url": "https://example.com", "method": "CUSTOM"}
+        )
+        result = tool.execute_action("any")
+        assert result["status_code"] is None
+        assert "Unsupported" in result["message"]
+
+    @patch("application.agents.tools.api_tool.validate_url")
+    @patch("application.agents.tools.api_tool.requests.put")
+    def test_put_method(self, mock_put, mock_validate):
+        tool = APITool(config={"url": "https://example.com/item/1", "method": "PUT"})
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.headers = {"Content-Type": "application/json"}
+        mock_resp.json.return_value = {}
+        mock_resp.content = b'{}'
+        mock_put.return_value = mock_resp
+
+        result = tool.execute_action("update", name="new")
+        assert result["status_code"] == 200
+
+    @patch("application.agents.tools.api_tool.validate_url")
+    @patch("application.agents.tools.api_tool.requests.delete")
+    def test_delete_method(self, mock_delete, mock_validate):
+        tool = APITool(config={"url": "https://example.com/item/1", "method": "DELETE"})
+        mock_resp = MagicMock()
+        mock_resp.status_code = 204
+        mock_resp.headers = {"Content-Type": "text/plain"}
+        mock_resp.content = b''
+        mock_delete.return_value = mock_resp
+
+        result = tool.execute_action("delete")
+        assert result["status_code"] == 204
+
+    @patch("application.agents.tools.api_tool.validate_url")
+    @patch("application.agents.tools.api_tool.requests.patch")
+    def test_patch_method(self, mock_patch, mock_validate):
+        tool = APITool(config={"url": "https://example.com/item/1", "method": "PATCH"})
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.headers = {"Content-Type": "application/json"}
+        mock_resp.json.return_value = {"patched": True}
+        mock_resp.content = b'{"patched":true}'
+        mock_patch.return_value = mock_resp
+
+        result = tool.execute_action("patch", field="val")
+        assert result["status_code"] == 200
+
+    @patch("application.agents.tools.api_tool.validate_url")
+    @patch("application.agents.tools.api_tool.requests.head")
+    def test_head_method(self, mock_head, mock_validate):
+        tool = APITool(config={"url": "https://example.com", "method": "HEAD"})
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.headers = {"Content-Type": "text/html"}
+        mock_resp.content = b''
+        mock_head.return_value = mock_resp
+
+        result = tool.execute_action("check")
+        assert result["status_code"] == 200
+
+    @patch("application.agents.tools.api_tool.validate_url")
+    @patch("application.agents.tools.api_tool.requests.options")
+    def test_options_method(self, mock_options, mock_validate):
+        tool = APITool(config={"url": "https://example.com", "method": "OPTIONS"})
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.headers = {"Content-Type": "text/plain"}
+        mock_resp.content = b''
+        mock_options.return_value = mock_resp
+
+        result = tool.execute_action("options")
+        assert result["status_code"] == 200
+
+
+@pytest.mark.unit
+class TestPathParamSubstitution:
+    @patch("application.agents.tools.api_tool.validate_url")
+    @patch("application.agents.tools.api_tool.requests.get")
+    def test_path_params_substituted(self, mock_get, mock_validate):
+        tool = APITool(
+            config={
+                "url": "https://api.example.com/users/{user_id}/posts/{post_id}",
+                "method": "GET",
+                "query_params": {"user_id": "42", "post_id": "7"},
+            }
+        )
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.headers = {"Content-Type": "application/json"}
+        mock_resp.json.return_value = []
+        mock_resp.content = b'[]'
+        mock_get.return_value = mock_resp
+
+        tool.execute_action("get")
+
+        called_url = mock_get.call_args[0][0]
+        assert "/users/42/posts/7" in called_url
+        assert "{user_id}" not in called_url
+
+
+@pytest.mark.unit
+class TestParseResponse:
+    def test_json_response(self, tool):
+        mock_resp = MagicMock()
+        mock_resp.headers = {"Content-Type": "application/json"}
+        mock_resp.json.return_value = {"key": "val"}
+        mock_resp.content = b'{"key":"val"}'
+
+        result = tool._parse_response(mock_resp)
+        assert result == {"key": "val"}
+
+    def test_text_response(self, tool):
+        mock_resp = MagicMock()
+        mock_resp.headers = {"Content-Type": "text/plain"}
+        mock_resp.text = "plain text"
+        mock_resp.content = b"plain text"
+
+        result = tool._parse_response(mock_resp)
+        assert result == "plain text"
+
+    def test_xml_response(self, tool):
+        mock_resp = MagicMock()
+        mock_resp.headers = {"Content-Type": "application/xml"}
+        mock_resp.text = "<root><item>1</item></root>"
+        mock_resp.content = b"<root><item>1</item></root>"
+
+        result = tool._parse_response(mock_resp)
+        assert "<root>" in result
+
+    def test_empty_content(self, tool):
+        mock_resp = MagicMock()
+        mock_resp.headers = {"Content-Type": "application/json"}
+        mock_resp.content = b""
+
+        result = tool._parse_response(mock_resp)
+        assert result is None
+
+    def test_html_response(self, tool):
+        mock_resp = MagicMock()
+        mock_resp.headers = {"Content-Type": "text/html"}
+        mock_resp.text = "<html><body>Hi</body></html>"
+        mock_resp.content = b"<html><body>Hi</body></html>"
+
+        result = tool._parse_response(mock_resp)
+        assert "<html>" in result
+
+
+@pytest.mark.unit
+class TestAPIToolMetadata:
+    def test_actions_metadata_empty(self, tool):
+        assert tool.get_actions_metadata() == []
+
+    def test_config_requirements_empty(self, tool):
+        assert tool.get_config_requirements() == {}
diff --git a/tests/agents/test_brave_tool.py b/tests/agents/test_brave_tool.py
new file mode 100644
index 00000000..0ff3c706
--- /dev/null
+++ b/tests/agents/test_brave_tool.py
@@ -0,0 +1,132 @@
+"""Tests for application/agents/tools/brave.py"""
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from application.agents.tools.brave import BraveSearchTool
+
+
+@pytest.fixture
+def tool():
+    return BraveSearchTool(config={"token": "test_api_key"})
+
+
+@pytest.mark.unit
+class TestBraveExecuteAction:
+    def test_unknown_action_raises(self, tool):
+        with pytest.raises(ValueError, match="Unknown action"):
+            tool.execute_action("invalid")
+
+    @patch("application.agents.tools.brave.requests.get")
+    def test_web_search_success(self, mock_get, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.json.return_value = {"web": {"results": [{"title": "Result"}]}}
+        mock_get.return_value = mock_resp
+
+        result = tool.execute_action("brave_web_search", query="python")
+
+        assert result["status_code"] == 200
+        assert "results" in result
+        assert "successfully" in result["message"]
+
+        call_kwargs = mock_get.call_args
+        assert call_kwargs[1]["headers"]["X-Subscription-Token"] == "test_api_key"
+
+    @patch("application.agents.tools.brave.requests.get")
+    def test_web_search_failure(self, mock_get, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 429
+        mock_get.return_value = mock_resp
+
+        result = tool.execute_action("brave_web_search", query="test")
+
+        assert result["status_code"] == 429
+        assert "failed" in result["message"].lower()
+
+    @patch("application.agents.tools.brave.requests.get")
+    def test_image_search_success(self, mock_get, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.json.return_value = {"results": [{"url": "https://img.com/1.jpg"}]}
+        mock_get.return_value = mock_resp
+
+        result = tool.execute_action("brave_image_search", query="cats")
+
+        assert result["status_code"] == 200
+        assert "results" in result
+
+    @patch("application.agents.tools.brave.requests.get")
+    def test_image_search_failure(self, mock_get, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 500
+        mock_get.return_value = mock_resp
+
+        result = tool.execute_action("brave_image_search", query="cats")
+
+        assert result["status_code"] == 500
+
+    @patch("application.agents.tools.brave.requests.get")
+    def test_count_capped_at_20(self, mock_get, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.json.return_value = {}
+        mock_get.return_value = mock_resp
+
+        tool.execute_action("brave_web_search", query="test", count=100)
+
+        params = mock_get.call_args[1]["params"]
+        assert params["count"] == 20
+
+    @patch("application.agents.tools.brave.requests.get")
+    def test_image_count_capped_at_100(self, mock_get, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.json.return_value = {}
+        mock_get.return_value = mock_resp
+
+        tool.execute_action("brave_image_search", query="test", count=500)
+
+        params = mock_get.call_args[1]["params"]
+        assert params["count"] == 100
+
+    @patch("application.agents.tools.brave.requests.get")
+    def test_freshness_param(self, mock_get, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.json.return_value = {}
+        mock_get.return_value = mock_resp
+
+        tool.execute_action("brave_web_search", query="news", freshness="pd")
+
+        params = mock_get.call_args[1]["params"]
+        assert params["freshness"] == "pd"
+
+    @patch("application.agents.tools.brave.requests.get")
+    def test_offset_capped(self, mock_get, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.json.return_value = {}
+        mock_get.return_value = mock_resp
+
+        tool.execute_action("brave_web_search", query="test", offset=100)
+
+        params = mock_get.call_args[1]["params"]
+        assert params["offset"] == 9
+
+
+@pytest.mark.unit
+class TestBraveMetadata:
+    def test_actions_metadata(self, tool):
+        meta = tool.get_actions_metadata()
+        assert len(meta) == 2
+        names = {a["name"] for a in meta}
+        assert "brave_web_search" in names
+        assert "brave_image_search" in names
+
+    def test_config_requirements(self, tool):
+        reqs = tool.get_config_requirements()
+        assert "token" in reqs
+        assert reqs["token"]["secret"] is True
+        assert reqs["token"]["required"] is True
diff --git a/tests/agents/test_cryptoprice_tool.py b/tests/agents/test_cryptoprice_tool.py
new file mode 100644
index 00000000..00f25b1c
--- /dev/null
+++ b/tests/agents/test_cryptoprice_tool.py
@@ -0,0 +1,85 @@
+"""Tests for application/agents/tools/cryptoprice.py"""
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from application.agents.tools.cryptoprice import CryptoPriceTool
+
+
+@pytest.fixture
+def tool():
+    return CryptoPriceTool(config={})
+
+
+@pytest.mark.unit
+class TestCryptoPriceExecuteAction:
+    def test_unknown_action_raises(self, tool):
+        with pytest.raises(ValueError, match="Unknown action"):
+            tool.execute_action("invalid_action")
+
+    @patch("application.agents.tools.cryptoprice.requests.get")
+    def test_successful_price_fetch(self, mock_get, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.json.return_value = {"USD": 65000}
+        mock_get.return_value = mock_resp
+
+        result = tool.execute_action("cryptoprice_get", symbol="BTC", currency="USD")
+
+        assert result["status_code"] == 200
+        assert result["price"] == 65000
+        assert "successfully" in result["message"]
+
+    @patch("application.agents.tools.cryptoprice.requests.get")
+    def test_currency_not_found(self, mock_get, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.json.return_value = {"EUR": 60000}
+        mock_get.return_value = mock_resp
+
+        result = tool.execute_action("cryptoprice_get", symbol="BTC", currency="USD")
+
+        assert result["status_code"] == 200
+        assert "Couldn't find" in result["message"]
+        assert "price" not in result
+
+    @patch("application.agents.tools.cryptoprice.requests.get")
+    def test_api_failure(self, mock_get, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 500
+        mock_get.return_value = mock_resp
+
+        result = tool.execute_action("cryptoprice_get", symbol="BTC", currency="USD")
+
+        assert result["status_code"] == 500
+        assert "Failed" in result["message"]
+
+    @patch("application.agents.tools.cryptoprice.requests.get")
+    def test_symbol_case_insensitive(self, mock_get, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.json.return_value = {"USD": 100}
+        mock_get.return_value = mock_resp
+
+        tool.execute_action("cryptoprice_get", symbol="btc", currency="usd")
+
+        called_url = mock_get.call_args[0][0]
+        assert "fsym=BTC" in called_url
+        assert "tsyms=USD" in called_url
+
+
+@pytest.mark.unit
+class TestCryptoPriceMetadata:
+    def test_actions_metadata(self, tool):
+        meta = tool.get_actions_metadata()
+        assert len(meta) == 1
+        assert meta[0]["name"] == "cryptoprice_get"
+        params = meta[0]["parameters"]
+        assert "symbol" in params["properties"]
+        assert "currency" in params["properties"]
+        assert "symbol" in params["required"]
+        assert "currency" in params["required"]
+
+    def test_config_requirements(self, tool):
+        assert tool.get_config_requirements() == {}
diff --git a/tests/agents/test_duckduckgo_tool.py b/tests/agents/test_duckduckgo_tool.py
new file mode 100644
index 00000000..3dc8727d
--- /dev/null
+++ b/tests/agents/test_duckduckgo_tool.py
@@ -0,0 +1,145 @@
+"""Tests for application/agents/tools/duckduckgo.py"""
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from application.agents.tools.duckduckgo import DuckDuckGoSearchTool
+
+
+@pytest.fixture
+def tool():
+    return DuckDuckGoSearchTool(config={})
+
+
+@pytest.mark.unit
+class TestDuckDuckGoExecuteAction:
+    def test_unknown_action_raises(self, tool):
+        with pytest.raises(ValueError, match="Unknown action"):
+            tool.execute_action("invalid")
+
+    @patch.object(DuckDuckGoSearchTool, "_get_ddgs_client")
+    def test_web_search_success(self, mock_client_factory, tool):
+        mock_client = MagicMock()
+        mock_client.text.return_value = [
+            {"title": "Result 1", "href": "https://example.com", "body": "snippet"}
+        ]
+        mock_client_factory.return_value = mock_client
+
+        result = tool.execute_action("ddg_web_search", query="python")
+
+        assert result["status_code"] == 200
+        assert len(result["results"]) == 1
+        assert "successfully" in result["message"]
+
+    @patch.object(DuckDuckGoSearchTool, "_get_ddgs_client")
+    def test_image_search_success(self, mock_client_factory, tool):
+        mock_client = MagicMock()
+        mock_client.images.return_value = [{"image": "https://img.com/1.jpg"}]
+        mock_client_factory.return_value = mock_client
+
+        result = tool.execute_action("ddg_image_search", query="cats")
+
+        assert result["status_code"] == 200
+        assert len(result["results"]) == 1
+
+    @patch.object(DuckDuckGoSearchTool, "_get_ddgs_client")
+    def test_news_search_success(self, mock_client_factory, tool):
+        mock_client = MagicMock()
+        mock_client.news.return_value = [{"title": "News"}]
+        mock_client_factory.return_value = mock_client
+
+        result = tool.execute_action("ddg_news_search", query="tech")
+
+        assert result["status_code"] == 200
+        assert len(result["results"]) == 1
+
+    @patch.object(DuckDuckGoSearchTool, "_get_ddgs_client")
+    def test_search_error_returns_500(self, mock_client_factory, tool):
+        mock_client = MagicMock()
+        mock_client.text.side_effect = Exception("Network error")
+        mock_client_factory.return_value = mock_client
+
+        result = tool.execute_action("ddg_web_search", query="test")
+
+        assert result["status_code"] == 500
+        assert "failed" in result["message"].lower()
+        assert result["results"] == []
+
+    @patch.object(DuckDuckGoSearchTool, "_get_ddgs_client")
+    def test_max_results_capped_at_20(self, mock_client_factory, tool):
+        mock_client = MagicMock()
+        mock_client.text.return_value = []
+        mock_client_factory.return_value = mock_client
+
+        tool.execute_action("ddg_web_search", query="test", max_results=100)
+
+        call_kwargs = mock_client.text.call_args[1]
+        assert call_kwargs["max_results"] == 20
+
+    @patch.object(DuckDuckGoSearchTool, "_get_ddgs_client")
+    def test_image_max_results_capped_at_50(self, mock_client_factory, tool):
+        mock_client = MagicMock()
+        mock_client.images.return_value = []
+        mock_client_factory.return_value = mock_client
+
+        tool.execute_action("ddg_image_search", query="test", max_results=200)
+
+        call_kwargs = mock_client.images.call_args[1]
+        assert call_kwargs["max_results"] == 50
+
+    @patch("application.agents.tools.duckduckgo.time.sleep")
+    @patch.object(DuckDuckGoSearchTool, "_get_ddgs_client")
+    def test_rate_limit_retries(self, mock_client_factory, mock_sleep, tool):
+        mock_client = MagicMock()
+        mock_client.text.side_effect = [
+            Exception("RateLimit exceeded"),
+            [{"title": "Result"}],
+        ]
+        mock_client_factory.return_value = mock_client
+
+        result = tool.execute_action("ddg_web_search", query="test")
+
+        assert result["status_code"] == 200
+        assert len(result["results"]) == 1
+        mock_sleep.assert_called_once()
+
+    @patch.object(DuckDuckGoSearchTool, "_get_ddgs_client")
+    def test_empty_results(self, mock_client_factory, tool):
+        mock_client = MagicMock()
+        mock_client.text.return_value = []
+        mock_client_factory.return_value = mock_client
+
+        result = tool.execute_action("ddg_web_search", query="obscure query")
+
+        assert result["status_code"] == 200
+        assert result["results"] == []
+
+    @patch.object(DuckDuckGoSearchTool, "_get_ddgs_client")
+    def test_none_results(self, mock_client_factory, tool):
+        mock_client = MagicMock()
+        mock_client.text.return_value = None
+        mock_client_factory.return_value = mock_client
+
+        result = tool.execute_action("ddg_web_search", query="test")
+
+        assert result["status_code"] == 200
+        assert result["results"] == []
+
+
+@pytest.mark.unit
+class TestDuckDuckGoMetadata:
+    def test_actions_metadata(self, tool):
+        meta = tool.get_actions_metadata()
+        assert len(meta) == 3
+        names = {a["name"] for a in meta}
+        assert "ddg_web_search" in names
+        assert "ddg_image_search" in names
+        assert "ddg_news_search" in names
+
+    def test_config_requirements(self, tool):
+        assert tool.get_config_requirements() == {}
+
+    def test_custom_timeout(self):
+        tool = DuckDuckGoSearchTool(config={"timeout": 30})
+        assert tool.timeout == 30
diff --git a/tests/agents/test_mcp_tool.py b/tests/agents/test_mcp_tool.py
new file mode 100644
index 00000000..eb17c757
--- /dev/null
+++ b/tests/agents/test_mcp_tool.py
@@ -0,0 +1,519 @@
+"""Tests for application/agents/tools/mcp_tool.py"""
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+
+# mcp_tool has a circular import at module level (mcp_tool -> tasks -> user -> mcp.py -> mcp_tool).
+# We must patch the dependencies BEFORE the module is first imported.
+@pytest.fixture(autouse=True)
+def _patch_mcp_globals(monkeypatch):
+    """Patch module-level MongoDB and cache to avoid real connections."""
+    import sys
+
+    # If the module is already loaded, just patch attributes directly
+    if "application.agents.tools.mcp_tool" in sys.modules:
+        mcp_mod = sys.modules["application.agents.tools.mcp_tool"]
+    else:
+        # Break the circular import by pre-populating the tasks import
+        # with a mock before mcp_tool tries to import it
+        mock_tasks = MagicMock()
+        monkeypatch.setitem(sys.modules, "application.api.user.tasks", mock_tasks)
+        import application.agents.tools.mcp_tool as mcp_mod
+
+    mock_mongo = MagicMock()
+    mock_db = MagicMock()
+    mock_db.__getitem__ = MagicMock(return_value=MagicMock())
+    monkeypatch.setattr(mcp_mod, "mongo", mock_mongo)
+    monkeypatch.setattr(mcp_mod, "db", mock_db)
+    monkeypatch.setattr(mcp_mod, "_mcp_clients_cache", {})
+
+
+@pytest.fixture
+def mcp_config():
+    return {
+        "server_url": "https://mcp.example.com/api",
+        "transport_type": "http",
+        "auth_type": "none",
+        "timeout": 10,
+    }
+
+
+@pytest.fixture
+def bearer_config():
+    return {
+        "server_url": "https://mcp.example.com/api",
+        "transport_type": "http",
+        "auth_type": "bearer",
+        "auth_credentials": {"bearer_token": "tok_123"},
+        "timeout": 10,
+    }
+
+
+@pytest.mark.unit
+class TestMCPToolInit:
+    def test_basic_init(self, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        with patch.object(MCPTool, "_setup_client"):
+            tool = MCPTool(mcp_config)
+
+            assert tool.server_url == "https://mcp.example.com/api"
+            assert tool.transport_type == "http"
+            assert tool.auth_type == "none"
+            assert tool.timeout == 10
+
+    def test_bearer_auth_credentials(self, bearer_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        with patch.object(MCPTool, "_setup_client"):
+            tool = MCPTool(bearer_config)
+            assert tool.auth_credentials["bearer_token"] == "tok_123"
+
+    def test_no_server_url_skips_setup(self):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        with patch.object(MCPTool, "_setup_client") as mock_setup:
+            MCPTool({"server_url": "", "auth_type": "none"})
+            mock_setup.assert_not_called()
+
+    def test_oauth_skips_setup(self):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        with patch.object(MCPTool, "_setup_client") as mock_setup:
+            MCPTool(
+                {
+                    "server_url": "https://mcp.example.com",
+                    "auth_type": "oauth",
+                }
+            )
+            mock_setup.assert_not_called()
+
+
+@pytest.mark.unit
+class TestGenerateCacheKey:
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_none_auth(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        assert "none" in tool._cache_key
+        assert "mcp.example.com" in tool._cache_key
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_bearer_auth(self, mock_setup, bearer_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(bearer_config)
+        assert "bearer:" in tool._cache_key
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_api_key_auth(self, mock_setup):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(
+            {
+                "server_url": "https://mcp.example.com",
+                "auth_type": "api_key",
+                "auth_credentials": {"api_key": "sk-test12345678"},
+            }
+        )
+        assert "apikey:" in tool._cache_key
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_basic_auth(self, mock_setup):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(
+            {
+                "server_url": "https://mcp.example.com",
+                "auth_type": "basic",
+                "auth_credentials": {"username": "user1", "password": "pass"},
+            }
+        )
+        assert "basic:user1" in tool._cache_key
+
+
+@pytest.mark.unit
+class TestCreateTransport:
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_http_transport(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        transport = tool._create_transport()
+        assert transport is not None
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_sse_transport(self, mock_setup):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(
+            {
+                "server_url": "https://mcp.example.com/sse",
+                "transport_type": "sse",
+                "auth_type": "none",
+            }
+        )
+        transport = tool._create_transport()
+        assert transport is not None
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_auto_detects_sse(self, mock_setup):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(
+            {
+                "server_url": "https://mcp.example.com/sse",
+                "transport_type": "auto",
+                "auth_type": "none",
+            }
+        )
+        transport = tool._create_transport()
+        assert transport is not None
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_stdio_transport_disabled(self, mock_setup):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(
+            {
+                "server_url": "https://mcp.example.com",
+                "transport_type": "stdio",
+                "auth_type": "none",
+            }
+        )
+        with pytest.raises(ValueError, match="STDIO transport is disabled"):
+            tool._create_transport()
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_api_key_header_injected(self, mock_setup):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(
+            {
+                "server_url": "https://mcp.example.com",
+                "transport_type": "http",
+                "auth_type": "api_key",
+                "auth_credentials": {
+                    "api_key": "sk-test",
+                    "api_key_header": "X-Custom-Key",
+                },
+            }
+        )
+        # _create_transport will be called; verify it doesn't raise
+        transport = tool._create_transport()
+        assert transport is not None
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_basic_auth_header_injected(self, mock_setup):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(
+            {
+                "server_url": "https://mcp.example.com",
+                "transport_type": "http",
+                "auth_type": "basic",
+                "auth_credentials": {"username": "user", "password": "pass"},
+            }
+        )
+        transport = tool._create_transport()
+        assert transport is not None
+
+
+@pytest.mark.unit
+class TestFormatTools:
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_format_list_of_dicts(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        result = tool._format_tools([{"name": "tool1", "description": "desc"}])
+        assert len(result) == 1
+        assert result[0]["name"] == "tool1"
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_format_tools_with_name_attribute(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        mock_tool = MagicMock()
+        mock_tool.name = "my_tool"
+        mock_tool.description = "A tool"
+        mock_tool.inputSchema = {"type": "object", "properties": {}}
+
+        result = tool._format_tools([mock_tool])
+        assert len(result) == 1
+        assert result[0]["name"] == "my_tool"
+        assert result[0]["inputSchema"] == {"type": "object", "properties": {}}
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_format_tools_response_object(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        resp = MagicMock()
+        resp.tools = [{"name": "t1", "description": "d1"}]
+
+        result = tool._format_tools(resp)
+        assert len(result) == 1
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_format_empty(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        assert tool._format_tools([]) == []
+        assert tool._format_tools("unexpected") == []
+
+
+@pytest.mark.unit
+class TestFormatResult:
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_format_result_with_content(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        mock_result = MagicMock()
+        text_item = MagicMock()
+        text_item.text = "Hello"
+        del text_item.data
+        mock_result.content = [text_item]
+        mock_result.isError = False
+
+        result = tool._format_result(mock_result)
+        assert result["content"][0]["type"] == "text"
+        assert result["content"][0]["text"] == "Hello"
+        assert result["isError"] is False
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_format_raw_result(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        raw = {"key": "value"}
+        assert tool._format_result(raw) == raw
+
+
+@pytest.mark.unit
+class TestExecuteAction:
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_no_server_raises(self, mock_setup):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool({"server_url": "", "auth_type": "none"})
+        with pytest.raises(Exception, match="No MCP server configured"):
+            tool.execute_action("test_action")
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    @patch("application.agents.tools.mcp_tool.MCPTool._run_async_operation")
+    def test_successful_execute(self, mock_run, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        tool._client = MagicMock()
+        mock_run.return_value = {"key": "value"}
+
+        result = tool.execute_action("test_action", param1="val1")
+
+        mock_run.assert_called_once_with("call_tool", "test_action", param1="val1")
+        assert result == {"key": "value"}
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    @patch("application.agents.tools.mcp_tool.MCPTool._run_async_operation")
+    def test_empty_kwargs_cleaned(self, mock_run, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        tool._client = MagicMock()
+        mock_run.return_value = {}
+
+        tool.execute_action("test", param1="", param2=None, param3="real")
+
+        call_kwargs = mock_run.call_args[1]
+        assert "param1" not in call_kwargs
+        assert "param2" not in call_kwargs
+        assert call_kwargs["param3"] == "real"
+
+
+@pytest.mark.unit
+class TestTestConnection:
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_no_server_url(self, mock_setup):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool({"server_url": "", "auth_type": "none"})
+        result = tool.test_connection()
+        assert result["success"] is False
+        assert "No server URL" in result["message"]
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_invalid_scheme(self, mock_setup):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(
+            {"server_url": "ftp://bad.com", "auth_type": "none"}
+        )
+        result = tool.test_connection()
+        assert result["success"] is False
+        assert "Invalid URL scheme" in result["message"]
+
+
+@pytest.mark.unit
+class TestMapError:
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_timeout_error(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+        import concurrent.futures
+
+        tool = MCPTool(mcp_config)
+        err = tool._map_error("test", concurrent.futures.TimeoutError())
+        assert "Timed out" in str(err)
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_connection_refused(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        err = tool._map_error("test", ConnectionRefusedError())
+        assert "Connection refused" in str(err)
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_403_forbidden(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        err = tool._map_error("test", Exception("403 Forbidden"))
+        assert "Access denied" in str(err)
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_ssl_error(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        err = tool._map_error("test", Exception("SSL certificate verify failed"))
+        assert "SSL" in str(err)
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_unknown_error_passthrough(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        original = RuntimeError("something weird")
+        err = tool._map_error("test", original)
+        assert err is original
+
+
+@pytest.mark.unit
+class TestGetActionsMetadata:
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_empty_tools(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        tool.available_tools = []
+        assert tool.get_actions_metadata() == []
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_tools_with_input_schema(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        tool.available_tools = [
+            {
+                "name": "search",
+                "description": "Search things",
+                "inputSchema": {
+                    "type": "object",
+                    "properties": {"query": {"type": "string"}},
+                    "required": ["query"],
+                },
+            }
+        ]
+        meta = tool.get_actions_metadata()
+        assert len(meta) == 1
+        assert meta[0]["name"] == "search"
+        assert "query" in meta[0]["parameters"]["properties"]
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_tools_without_schema(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        tool.available_tools = [{"name": "ping", "description": "Ping"}]
+        meta = tool.get_actions_metadata()
+        assert meta[0]["parameters"]["properties"] == {}
+
+    @patch("application.agents.tools.mcp_tool.MCPTool._setup_client")
+    def test_config_requirements(self, mock_setup, mcp_config):
+        from application.agents.tools.mcp_tool import MCPTool
+
+        tool = MCPTool(mcp_config)
+        reqs = tool.get_config_requirements()
+        assert "server_url" in reqs
+        assert "auth_type" in reqs
+        assert reqs["server_url"]["required"] is True
+
+
+@pytest.mark.unit
+class TestMCPOAuthManager:
+    def test_handle_callback_success(self):
+        from application.agents.tools.mcp_tool import MCPOAuthManager
+
+        mock_redis = MagicMock()
+        manager = MCPOAuthManager(mock_redis)
+
+        result = manager.handle_oauth_callback(state="abc123", code="auth_code")
+
+        assert result is True
+        mock_redis.setex.assert_called()
+
+    def test_handle_callback_no_redis(self):
+        from application.agents.tools.mcp_tool import MCPOAuthManager
+
+        manager = MCPOAuthManager(None)
+        result = manager.handle_oauth_callback(state="abc", code="code")
+        assert result is False
+
+    def test_handle_callback_error(self):
+        from application.agents.tools.mcp_tool import MCPOAuthManager
+
+        mock_redis = MagicMock()
+        manager = MCPOAuthManager(mock_redis)
+
+        result = manager.handle_oauth_callback(
+            state="abc", code="", error="access_denied"
+        )
+        assert result is False
+
+    def test_get_oauth_status_no_task(self):
+        from application.agents.tools.mcp_tool import MCPOAuthManager
+
+        manager = MCPOAuthManager(MagicMock())
+        result = manager.get_oauth_status("")
+        assert result["status"] == "not_started"
+
+
+@pytest.mark.unit
+class TestDBTokenStorage:
+    def test_get_base_url(self):
+        from application.agents.tools.mcp_tool import DBTokenStorage
+
+        assert (
+            DBTokenStorage.get_base_url("https://mcp.example.com/api/v1")
+            == "https://mcp.example.com"
+        )
+
+    def test_get_db_key(self):
+        from application.agents.tools.mcp_tool import DBTokenStorage
+
+        mock_db = MagicMock()
+        storage = DBTokenStorage(
+            server_url="https://mcp.example.com/api",
+            user_id="user1",
+            db_client=mock_db,
+        )
+        key = storage.get_db_key()
+        assert key["server_url"] == "https://mcp.example.com"
+        assert key["user_id"] == "user1"
diff --git a/tests/agents/test_ntfy_tool.py b/tests/agents/test_ntfy_tool.py
new file mode 100644
index 00000000..ab5f0bdc
--- /dev/null
+++ b/tests/agents/test_ntfy_tool.py
@@ -0,0 +1,146 @@
+"""Tests for application/agents/tools/ntfy.py"""
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from application.agents.tools.ntfy import NtfyTool
+
+
+@pytest.fixture
+def tool():
+    return NtfyTool(config={"token": "test_token"})
+
+
+@pytest.fixture
+def tool_no_token():
+    return NtfyTool(config={})
+
+
+@pytest.mark.unit
+class TestNtfyExecuteAction:
+    def test_unknown_action_raises(self, tool):
+        with pytest.raises(ValueError, match="Unknown action"):
+            tool.execute_action("bad_action")
+
+    @patch("application.agents.tools.ntfy.requests.post")
+    def test_send_message_basic(self, mock_post, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_post.return_value = mock_resp
+
+        result = tool.execute_action(
+            "ntfy_send_message",
+            server_url="https://ntfy.sh",
+            message="Hello",
+            topic="test",
+        )
+
+        assert result["status_code"] == 200
+        assert result["message"] == "Message sent"
+        mock_post.assert_called_once()
+        call_args = mock_post.call_args
+        assert call_args[0][0] == "https://ntfy.sh/test"
+        assert call_args[1]["data"] == b"Hello"
+
+    @patch("application.agents.tools.ntfy.requests.post")
+    def test_send_with_title_and_priority(self, mock_post, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_post.return_value = mock_resp
+
+        tool.execute_action(
+            "ntfy_send_message",
+            server_url="https://ntfy.sh",
+            message="Alert",
+            topic="urgent",
+            title="Warning",
+            priority=5,
+        )
+
+        headers = mock_post.call_args[1]["headers"]
+        assert headers["X-Title"] == "Warning"
+        assert headers["X-Priority"] == "5"
+
+    @patch("application.agents.tools.ntfy.requests.post")
+    def test_auth_header_with_token(self, mock_post, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_post.return_value = mock_resp
+
+        tool.execute_action(
+            "ntfy_send_message",
+            server_url="https://ntfy.sh",
+            message="Hi",
+            topic="t",
+        )
+
+        headers = mock_post.call_args[1]["headers"]
+        assert headers["Authorization"] == "Basic test_token"
+
+    @patch("application.agents.tools.ntfy.requests.post")
+    def test_no_auth_without_token(self, mock_post, tool_no_token):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_post.return_value = mock_resp
+
+        tool_no_token.execute_action(
+            "ntfy_send_message",
+            server_url="https://ntfy.sh",
+            message="Hi",
+            topic="t",
+        )
+
+        headers = mock_post.call_args[1]["headers"]
+        assert "Authorization" not in headers
+
+    def test_invalid_priority_raises(self, tool):
+        with pytest.raises(ValueError, match="between 1 and 5"):
+            tool.execute_action(
+                "ntfy_send_message",
+                server_url="https://ntfy.sh",
+                message="Hi",
+                topic="t",
+                priority=10,
+            )
+
+    def test_non_numeric_priority_raises(self, tool):
+        with pytest.raises(ValueError, match="convertible to an integer"):
+            tool.execute_action(
+                "ntfy_send_message",
+                server_url="https://ntfy.sh",
+                message="Hi",
+                topic="t",
+                priority="abc",
+            )
+
+    @patch("application.agents.tools.ntfy.requests.post")
+    def test_trailing_slash_stripped(self, mock_post, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_post.return_value = mock_resp
+
+        tool.execute_action(
+            "ntfy_send_message",
+            server_url="https://ntfy.sh/",
+            message="Hi",
+            topic="test",
+        )
+
+        assert mock_post.call_args[0][0] == "https://ntfy.sh/test"
+
+
+@pytest.mark.unit
+class TestNtfyMetadata:
+    def test_actions_metadata(self, tool):
+        meta = tool.get_actions_metadata()
+        assert len(meta) == 1
+        assert meta[0]["name"] == "ntfy_send_message"
+        assert "server_url" in meta[0]["parameters"]["properties"]
+        assert "message" in meta[0]["parameters"]["properties"]
+        assert "topic" in meta[0]["parameters"]["properties"]
+
+    def test_config_requirements(self, tool):
+        reqs = tool.get_config_requirements()
+        assert "token" in reqs
+        assert reqs["token"]["secret"] is True
diff --git a/tests/agents/test_postgres_tool.py b/tests/agents/test_postgres_tool.py
new file mode 100644
index 00000000..6610883a
--- /dev/null
+++ b/tests/agents/test_postgres_tool.py
@@ -0,0 +1,146 @@
+"""Tests for application/agents/tools/postgres.py"""
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from application.agents.tools.postgres import PostgresTool
+
+
+@pytest.fixture
+def tool():
+    return PostgresTool(config={"token": "postgresql://user:pass@localhost/testdb"})
+
+
+@pytest.mark.unit
+class TestPostgresExecuteAction:
+    def test_unknown_action_raises(self, tool):
+        with pytest.raises(ValueError, match="Unknown action"):
+            tool.execute_action("invalid")
+
+    @patch("application.agents.tools.postgres.psycopg2.connect")
+    def test_select_query(self, mock_connect, tool):
+        mock_conn = MagicMock()
+        mock_cur = MagicMock()
+        mock_cur.description = [("id",), ("name",)]
+        mock_cur.fetchall.return_value = [(1, "Alice"), (2, "Bob")]
+        mock_conn.cursor.return_value = mock_cur
+        mock_connect.return_value = mock_conn
+
+        result = tool.execute_action(
+            "postgres_execute_sql", sql_query="SELECT id, name FROM users"
+        )
+
+        assert result["status_code"] == 200
+        assert result["response_data"]["column_names"] == ["id", "name"]
+        assert len(result["response_data"]["data"]) == 2
+        assert result["response_data"]["data"][0] == {"id": 1, "name": "Alice"}
+        mock_conn.close.assert_called_once()
+
+    @patch("application.agents.tools.postgres.psycopg2.connect")
+    def test_insert_query(self, mock_connect, tool):
+        mock_conn = MagicMock()
+        mock_cur = MagicMock()
+        mock_cur.rowcount = 1
+        mock_conn.cursor.return_value = mock_cur
+        mock_connect.return_value = mock_conn
+
+        result = tool.execute_action(
+            "postgres_execute_sql",
+            sql_query="INSERT INTO users (name) VALUES ('Alice')",
+        )
+
+        assert result["status_code"] == 200
+        assert "1 rows affected" in result["response_data"]["message"]
+        mock_conn.commit.assert_called_once()
+        mock_conn.close.assert_called_once()
+
+    @patch("application.agents.tools.postgres.psycopg2.connect")
+    def test_db_error(self, mock_connect, tool):
+        import psycopg2
+
+        mock_connect.side_effect = psycopg2.Error("connection refused")
+
+        result = tool.execute_action(
+            "postgres_execute_sql", sql_query="SELECT 1"
+        )
+
+        assert result["status_code"] == 500
+        assert "Database error" in result["error"]
+
+    @patch("application.agents.tools.postgres.psycopg2.connect")
+    def test_get_schema(self, mock_connect, tool):
+        mock_conn = MagicMock()
+        mock_cur = MagicMock()
+        mock_cur.fetchall.return_value = [
+            ("users", "id", "integer", "nextval(...)", "NO"),
+            ("users", "name", "varchar", None, "YES"),
+            ("posts", "id", "integer", "nextval(...)", "NO"),
+        ]
+        mock_conn.cursor.return_value = mock_cur
+        mock_connect.return_value = mock_conn
+
+        result = tool.execute_action("postgres_get_schema", db_name="testdb")
+
+        assert result["status_code"] == 200
+        assert "users" in result["schema"]
+        assert "posts" in result["schema"]
+        assert len(result["schema"]["users"]) == 2
+        assert result["schema"]["users"][0]["column_name"] == "id"
+        mock_conn.close.assert_called_once()
+
+    @patch("application.agents.tools.postgres.psycopg2.connect")
+    def test_get_schema_db_error(self, mock_connect, tool):
+        import psycopg2
+
+        mock_connect.side_effect = psycopg2.Error("auth failed")
+
+        result = tool.execute_action("postgres_get_schema", db_name="testdb")
+
+        assert result["status_code"] == 500
+        assert "Database error" in result["error"]
+
+    @patch("application.agents.tools.postgres.psycopg2.connect")
+    def test_connection_closed_on_error(self, mock_connect, tool):
+        import psycopg2
+
+        mock_conn = MagicMock()
+        mock_cur = MagicMock()
+        mock_cur.execute.side_effect = psycopg2.Error("syntax error")
+        mock_conn.cursor.return_value = mock_cur
+        mock_connect.return_value = mock_conn
+
+        tool.execute_action("postgres_execute_sql", sql_query="BAD SQL")
+
+        mock_conn.close.assert_called_once()
+
+    @patch("application.agents.tools.postgres.psycopg2.connect")
+    def test_select_with_no_description(self, mock_connect, tool):
+        mock_conn = MagicMock()
+        mock_cur = MagicMock()
+        mock_cur.description = None
+        mock_cur.fetchall.return_value = []
+        mock_conn.cursor.return_value = mock_cur
+        mock_connect.return_value = mock_conn
+
+        result = tool.execute_action(
+            "postgres_execute_sql", sql_query="SELECT 1 WHERE false"
+        )
+
+        assert result["status_code"] == 200
+        assert result["response_data"]["column_names"] == []
+
+
+@pytest.mark.unit
+class TestPostgresMetadata:
+    def test_actions_metadata(self, tool):
+        meta = tool.get_actions_metadata()
+        assert len(meta) == 2
+        names = {a["name"] for a in meta}
+        assert "postgres_execute_sql" in names
+        assert "postgres_get_schema" in names
+
+    def test_config_requirements(self, tool):
+        reqs = tool.get_config_requirements()
+        assert "token" in reqs
+        assert reqs["token"]["secret"] is True
diff --git a/tests/agents/test_read_webpage_tool.py b/tests/agents/test_read_webpage_tool.py
new file mode 100644
index 00000000..7a568ba4
--- /dev/null
+++ b/tests/agents/test_read_webpage_tool.py
@@ -0,0 +1,86 @@
+"""Tests for application/agents/tools/read_webpage.py"""
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+import requests
+
+from application.agents.tools.read_webpage import ReadWebpageTool
+
+
+@pytest.fixture
+def tool():
+    return ReadWebpageTool()
+
+
+@pytest.mark.unit
+class TestReadWebpageExecuteAction:
+    def test_unknown_action(self, tool):
+        result = tool.execute_action("unknown_action")
+        assert "Error" in result
+        assert "Unknown action" in result
+
+    def test_missing_url(self, tool):
+        result = tool.execute_action("read_webpage")
+        assert "Error" in result
+        assert "URL parameter is missing" in result
+
+    @patch("application.agents.tools.read_webpage.validate_url")
+    @patch("application.agents.tools.read_webpage.requests.get")
+    def test_successful_fetch(self, mock_get, mock_validate, tool):
+        mock_validate.return_value = "https://example.com"
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_resp.text = "<html><body><h1>Title</h1><p>Content</p></body></html>"
+        mock_get.return_value = mock_resp
+
+        result = tool.execute_action("read_webpage", url="https://example.com")
+
+        assert "Title" in result
+        assert "Content" in result
+
+    @patch("application.agents.tools.read_webpage.validate_url")
+    @patch("application.agents.tools.read_webpage.requests.get")
+    def test_request_error(self, mock_get, mock_validate, tool):
+        mock_validate.return_value = "https://example.com"
+        mock_get.side_effect = requests.exceptions.ConnectionError("refused")
+
+        result = tool.execute_action("read_webpage", url="https://example.com")
+
+        assert "Error fetching URL" in result
+
+    @patch("application.agents.tools.read_webpage.validate_url")
+    def test_ssrf_blocked(self, mock_validate, tool):
+        from application.core.url_validation import SSRFError
+
+        mock_validate.side_effect = SSRFError("blocked")
+
+        result = tool.execute_action("read_webpage", url="http://169.254.169.254/")
+
+        assert "Error" in result
+        assert "validation failed" in result
+
+    @patch("application.agents.tools.read_webpage.validate_url")
+    @patch("application.agents.tools.read_webpage.requests.get")
+    def test_http_error(self, mock_get, mock_validate, tool):
+        mock_validate.return_value = "https://example.com/404"
+        mock_resp = MagicMock()
+        mock_resp.raise_for_status.side_effect = requests.exceptions.HTTPError("404")
+        mock_get.return_value = mock_resp
+
+        result = tool.execute_action("read_webpage", url="https://example.com/404")
+
+        assert "Error fetching URL" in result
+
+
+@pytest.mark.unit
+class TestReadWebpageMetadata:
+    def test_actions_metadata(self, tool):
+        meta = tool.get_actions_metadata()
+        assert len(meta) == 1
+        assert meta[0]["name"] == "read_webpage"
+        assert "url" in meta[0]["parameters"]["properties"]
+        assert "url" in meta[0]["parameters"]["required"]
+
+    def test_config_requirements(self, tool):
+        assert tool.get_config_requirements() == {}
diff --git a/tests/agents/test_spec_parser.py b/tests/agents/test_spec_parser.py
new file mode 100644
index 00000000..cb6eb779
--- /dev/null
+++ b/tests/agents/test_spec_parser.py
@@ -0,0 +1,335 @@
+"""Tests for application/agents/tools/spec_parser.py"""
+
+import json
+
+import pytest
+
+from application.agents.tools.spec_parser import (
+    _extract_metadata,
+    _generate_action_name,
+    _get_base_url,
+    _load_spec,
+    _param_to_property,
+    _resolve_ref,
+    _validate_spec,
+    parse_spec,
+)
+
+
+MINIMAL_OPENAPI = json.dumps(
+    {
+        "openapi": "3.0.0",
+        "info": {"title": "Test API", "version": "1.0.0"},
+        "servers": [{"url": "https://api.example.com"}],
+        "paths": {
+            "/users": {
+                "get": {
+                    "operationId": "listUsers",
+                    "summary": "List all users",
+                    "parameters": [
+                        {
+                            "name": "limit",
+                            "in": "query",
+                            "schema": {"type": "integer"},
+                        }
+                    ],
+                    "responses": {"200": {"description": "OK"}},
+                }
+            }
+        },
+    }
+)
+
+MINIMAL_SWAGGER = json.dumps(
+    {
+        "swagger": "2.0",
+        "info": {"title": "Swagger API", "version": "2.0.0"},
+        "host": "api.example.com",
+        "basePath": "/v1",
+        "schemes": ["https"],
+        "paths": {
+            "/pets": {
+                "get": {
+                    "operationId": "listPets",
+                    "summary": "List pets",
+                    "parameters": [],
+                    "responses": {"200": {"description": "OK"}},
+                }
+            }
+        },
+    }
+)
+
+
+@pytest.mark.unit
+class TestLoadSpec:
+    def test_load_json(self):
+        spec = _load_spec('{"openapi": "3.0.0"}')
+        assert spec["openapi"] == "3.0.0"
+
+    def test_load_yaml(self):
+        spec = _load_spec("openapi: '3.0.0'\ninfo:\n  title: Test")
+        assert spec["openapi"] == "3.0.0"
+
+    def test_empty_raises(self):
+        with pytest.raises(ValueError, match="Empty"):
+            _load_spec("")
+
+    def test_whitespace_only_raises(self):
+        with pytest.raises(ValueError, match="Empty"):
+            _load_spec("   \n  ")
+
+    def test_invalid_json_raises(self):
+        with pytest.raises(ValueError, match="Invalid"):
+            _load_spec("{invalid json}")
+
+
+@pytest.mark.unit
+class TestValidateSpec:
+    def test_valid_openapi(self):
+        spec = json.loads(MINIMAL_OPENAPI)
+        _validate_spec(spec)  # should not raise
+
+    def test_valid_swagger(self):
+        spec = json.loads(MINIMAL_SWAGGER)
+        _validate_spec(spec)
+
+    def test_missing_version_raises(self):
+        with pytest.raises(ValueError, match="Unsupported"):
+            _validate_spec({"paths": {"/a": {}}})
+
+    def test_no_paths_raises(self):
+        with pytest.raises(ValueError, match="No API paths"):
+            _validate_spec({"openapi": "3.0.0"})
+
+    def test_empty_paths_raises(self):
+        with pytest.raises(ValueError, match="No API paths"):
+            _validate_spec({"openapi": "3.0.0", "paths": {}})
+
+    def test_non_dict_raises(self):
+        with pytest.raises(ValueError, match="valid object"):
+            _validate_spec("not a dict")
+
+
+@pytest.mark.unit
+class TestExtractMetadata:
+    def test_openapi_metadata(self):
+        spec = json.loads(MINIMAL_OPENAPI)
+        meta = _extract_metadata(spec, is_swagger=False)
+        assert meta["title"] == "Test API"
+        assert meta["version"] == "1.0.0"
+        assert meta["base_url"] == "https://api.example.com"
+
+    def test_swagger_metadata(self):
+        spec = json.loads(MINIMAL_SWAGGER)
+        meta = _extract_metadata(spec, is_swagger=True)
+        assert meta["title"] == "Swagger API"
+        assert meta["base_url"] == "https://api.example.com/v1"
+
+    def test_missing_info(self):
+        spec = {"openapi": "3.0.0", "paths": {"/a": {}}}
+        meta = _extract_metadata(spec, is_swagger=False)
+        assert meta["title"] == "Untitled API"
+
+    def test_description_truncated(self):
+        spec = {
+            "openapi": "3.0.0",
+            "info": {"title": "T", "description": "x" * 1000},
+            "paths": {"/a": {}},
+        }
+        meta = _extract_metadata(spec, is_swagger=False)
+        assert len(meta["description"]) <= 500
+
+
+@pytest.mark.unit
+class TestGetBaseUrl:
+    def test_openapi_servers(self):
+        spec = {"servers": [{"url": "https://api.example.com/v2/"}]}
+        assert _get_base_url(spec, is_swagger=False) == "https://api.example.com/v2"
+
+    def test_openapi_no_servers(self):
+        assert _get_base_url({}, is_swagger=False) == ""
+
+    def test_swagger_with_host(self):
+        spec = {"host": "api.test.com", "basePath": "/v1", "schemes": ["https"]}
+        assert _get_base_url(spec, is_swagger=True) == "https://api.test.com/v1"
+
+    def test_swagger_no_host(self):
+        assert _get_base_url({}, is_swagger=True) == ""
+
+    def test_swagger_default_scheme(self):
+        spec = {"host": "api.test.com", "basePath": ""}
+        assert _get_base_url(spec, is_swagger=True) == "https://api.test.com"
+
+
+@pytest.mark.unit
+class TestGenerateActionName:
+    def test_uses_operation_id(self):
+        assert _generate_action_name({"operationId": "getUser"}, "get", "/users") == "getUser"
+
+    def test_fallback_to_method_path(self):
+        name = _generate_action_name({}, "get", "/users/{id}")
+        assert name.startswith("get_")
+        assert "users" in name
+
+    def test_truncates_long_names(self):
+        name = _generate_action_name({}, "get", "/" + "a" * 200)
+        assert len(name) <= 64
+
+    def test_sanitizes_special_chars(self):
+        name = _generate_action_name({"operationId": "get.user@v2"}, "get", "/")
+        assert "." not in name
+        assert "@" not in name
+
+
+@pytest.mark.unit
+class TestParamToProperty:
+    def test_string_param(self):
+        param = {"name": "q", "in": "query", "schema": {"type": "string"}}
+        prop = _param_to_property(param)
+        assert prop["type"] == "string"
+        assert prop["required"] is False
+
+    def test_integer_param(self):
+        param = {
+            "name": "limit",
+            "in": "query",
+            "required": True,
+            "schema": {"type": "integer"},
+        }
+        prop = _param_to_property(param)
+        assert prop["type"] == "integer"
+        assert prop["required"] is True
+        assert prop["filled_by_llm"] is True
+
+    def test_number_maps_to_integer(self):
+        param = {"name": "score", "in": "query", "schema": {"type": "number"}}
+        prop = _param_to_property(param)
+        assert prop["type"] == "integer"
+
+
+@pytest.mark.unit
+class TestResolveRef:
+    def test_no_ref(self):
+        obj = {"type": "string"}
+        assert _resolve_ref(obj, {}, {}) == obj
+
+    def test_components_ref(self):
+        components = {"schemas": {"User": {"type": "object", "properties": {"name": {"type": "string"}}}}}
+        obj = {"$ref": "#/components/schemas/User"}
+        result = _resolve_ref(obj, components, {})
+        assert result["type"] == "object"
+
+    def test_definitions_ref(self):
+        definitions = {"Pet": {"type": "object"}}
+        obj = {"$ref": "#/definitions/Pet"}
+        result = _resolve_ref(obj, {}, definitions)
+        assert result["type"] == "object"
+
+    def test_unsupported_ref(self):
+        obj = {"$ref": "#/external/something"}
+        assert _resolve_ref(obj, {}, {}) is None
+
+    def test_non_dict_returns_none(self):
+        assert _resolve_ref("string", {}, {}) is None
+        assert _resolve_ref(42, {}, {}) is None
+
+
+@pytest.mark.unit
+class TestParseSpec:
+    def test_openapi_full_parse(self):
+        metadata, actions = parse_spec(MINIMAL_OPENAPI)
+        assert metadata["title"] == "Test API"
+        assert len(actions) == 1
+        assert actions[0]["name"] == "listUsers"
+        assert actions[0]["method"] == "GET"
+        assert actions[0]["url"] == "https://api.example.com/users"
+        assert "limit" in actions[0]["query_params"]["properties"]
+
+    def test_swagger_full_parse(self):
+        metadata, actions = parse_spec(MINIMAL_SWAGGER)
+        assert metadata["title"] == "Swagger API"
+        assert len(actions) == 1
+        assert actions[0]["name"] == "listPets"
+        assert actions[0]["method"] == "GET"
+
+    def test_multiple_methods(self):
+        spec = json.dumps(
+            {
+                "openapi": "3.0.0",
+                "info": {"title": "T", "version": "1"},
+                "paths": {
+                    "/items": {
+                        "get": {"operationId": "listItems", "responses": {}},
+                        "post": {
+                            "operationId": "createItem",
+                            "requestBody": {
+                                "content": {
+                                    "application/json": {
+                                        "schema": {
+                                            "type": "object",
+                                            "properties": {
+                                                "name": {"type": "string"}
+                                            },
+                                            "required": ["name"],
+                                        }
+                                    }
+                                }
+                            },
+                            "responses": {},
+                        },
+                    }
+                },
+            }
+        )
+        metadata, actions = parse_spec(spec)
+        assert len(actions) == 2
+        names = {a["name"] for a in actions}
+        assert "listItems" in names
+        assert "createItem" in names
+
+        create = next(a for a in actions if a["name"] == "createItem")
+        assert "name" in create["body"]["properties"]
+
+    def test_header_params(self):
+        spec = json.dumps(
+            {
+                "openapi": "3.0.0",
+                "info": {"title": "T", "version": "1"},
+                "paths": {
+                    "/data": {
+                        "get": {
+                            "operationId": "getData",
+                            "parameters": [
+                                {"name": "X-API-Key", "in": "header", "schema": {"type": "string"}}
+                            ],
+                            "responses": {},
+                        }
+                    }
+                },
+            }
+        )
+        _, actions = parse_spec(spec)
+        assert "X-API-Key" in actions[0]["headers"]["properties"]
+
+    def test_invalid_spec_raises(self):
+        with pytest.raises(ValueError):
+            parse_spec("")
+
+    def test_yaml_spec(self):
+        yaml_spec = """
+openapi: "3.0.0"
+info:
+  title: YAML API
+  version: "1.0"
+paths:
+  /health:
+    get:
+      operationId: healthCheck
+      responses:
+        "200":
+          description: OK
+"""
+        metadata, actions = parse_spec(yaml_spec)
+        assert metadata["title"] == "YAML API"
+        assert actions[0]["name"] == "healthCheck"
diff --git a/tests/agents/test_telegram_tool.py b/tests/agents/test_telegram_tool.py
new file mode 100644
index 00000000..f0e8b0e9
--- /dev/null
+++ b/tests/agents/test_telegram_tool.py
@@ -0,0 +1,79 @@
+"""Tests for application/agents/tools/telegram.py"""
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from application.agents.tools.telegram import TelegramTool
+
+
+@pytest.fixture
+def tool():
+    return TelegramTool(config={"token": "bot123:ABC"})
+
+
+@pytest.mark.unit
+class TestTelegramExecuteAction:
+    def test_unknown_action_raises(self, tool):
+        with pytest.raises(ValueError, match="Unknown action"):
+            tool.execute_action("invalid")
+
+    @patch("application.agents.tools.telegram.requests.post")
+    def test_send_message(self, mock_post, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_post.return_value = mock_resp
+
+        result = tool.execute_action(
+            "telegram_send_message", text="Hello", chat_id="12345"
+        )
+
+        assert result["status_code"] == 200
+        assert result["message"] == "Message sent"
+        call_args = mock_post.call_args
+        assert "bot123:ABC/sendMessage" in call_args[0][0]
+        assert call_args[1]["data"]["text"] == "Hello"
+        assert call_args[1]["data"]["chat_id"] == "12345"
+
+    @patch("application.agents.tools.telegram.requests.post")
+    def test_send_image(self, mock_post, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 200
+        mock_post.return_value = mock_resp
+
+        result = tool.execute_action(
+            "telegram_send_image", image_url="https://img.com/cat.jpg", chat_id="12345"
+        )
+
+        assert result["status_code"] == 200
+        assert result["message"] == "Image sent"
+        call_args = mock_post.call_args
+        assert "bot123:ABC/sendPhoto" in call_args[0][0]
+        assert call_args[1]["data"]["photo"] == "https://img.com/cat.jpg"
+
+    @patch("application.agents.tools.telegram.requests.post")
+    def test_api_error_status(self, mock_post, tool):
+        mock_resp = MagicMock()
+        mock_resp.status_code = 403
+        mock_post.return_value = mock_resp
+
+        result = tool.execute_action(
+            "telegram_send_message", text="Hi", chat_id="999"
+        )
+
+        assert result["status_code"] == 403
+
+
+@pytest.mark.unit
+class TestTelegramMetadata:
+    def test_actions_metadata(self, tool):
+        meta = tool.get_actions_metadata()
+        assert len(meta) == 2
+        names = {a["name"] for a in meta}
+        assert "telegram_send_message" in names
+        assert "telegram_send_image" in names
+
+    def test_config_requirements(self, tool):
+        reqs = tool.get_config_requirements()
+        assert "token" in reqs
+        assert reqs["token"]["secret"] is True
diff --git a/tests/api/answer/routes/test_answer.py b/tests/api/answer/routes/test_answer.py
new file mode 100644
index 00000000..53f2525d
--- /dev/null
+++ b/tests/api/answer/routes/test_answer.py
@@ -0,0 +1,235 @@
+"""Tests for application/api/answer/routes/answer.py"""
+
+import json
+from unittest.mock import MagicMock, patch
+
+import pytest
+from bson import ObjectId
+
+
+@pytest.fixture
+def mock_stream_processor():
+    """Create a mock StreamProcessor."""
+    with patch(
+        "application.api.answer.routes.answer.StreamProcessor"
+    ) as MockProcessor:
+        processor = MagicMock()
+        processor.decoded_token = {"sub": "test_user"}
+        processor.conversation_id = str(ObjectId())
+        processor.agent_config = {}
+        processor.agent_id = str(ObjectId())
+        processor.is_shared_usage = False
+        processor.shared_token = None
+        processor.model_id = "gpt-4"
+        processor.build_agent.return_value = MagicMock()
+        MockProcessor.return_value = processor
+        yield processor
+
+
+@pytest.fixture
+def answer_client(mock_mongo_db, flask_app):
+    """Create a test client with the answer route registered."""
+    from flask_restx import Api
+
+    from application.api.answer.routes.answer import answer_ns
+
+    api = Api(flask_app)
+    api.add_namespace(answer_ns)
+    flask_app.config["TESTING"] = True
+    return flask_app.test_client()
+
+
+@pytest.mark.unit
+class TestAnswerResourcePost:
+    def test_missing_question_returns_400(self, answer_client, mock_stream_processor):
+        resp = answer_client.post(
+            "/api/answer",
+            data=json.dumps({}),
+            content_type="application/json",
+        )
+        assert resp.status_code == 400
+
+    def test_successful_answer(self, answer_client, mock_stream_processor):
+        conv_id = str(ObjectId())
+        with patch.object(
+            mock_stream_processor.build_agent.return_value,
+            "gen",
+            return_value=iter([]),
+        ):
+            with patch(
+                "application.api.answer.routes.answer.AnswerResource.validate_request",
+                return_value=None,
+            ), patch(
+                "application.api.answer.routes.answer.AnswerResource.check_usage",
+                return_value=None,
+            ), patch(
+                "application.api.answer.routes.answer.AnswerResource.complete_stream",
+                return_value=iter(
+                    [
+                        f'data: {json.dumps({"type": "answer", "answer": "Hello"})}\n\n',
+                        f'data: {json.dumps({"type": "id", "id": conv_id})}\n\n',
+                        f'data: {json.dumps({"type": "end"})}\n\n',
+                    ]
+                ),
+            ), patch(
+                "application.api.answer.routes.answer.AnswerResource.process_response_stream",
+                return_value=(conv_id, "Hello", [], [], "", None),
+            ):
+                resp = answer_client.post(
+                    "/api/answer",
+                    data=json.dumps({"question": "What is Python?"}),
+                    content_type="application/json",
+                )
+                assert resp.status_code == 200
+                data = resp.get_json()
+                assert data["answer"] == "Hello"
+                assert data["conversation_id"] == conv_id
+
+    def test_unauthorized_returns_401(self, answer_client, mock_stream_processor):
+        mock_stream_processor.decoded_token = None
+        with patch(
+            "application.api.answer.routes.answer.AnswerResource.validate_request",
+            return_value=None,
+        ):
+            resp = answer_client.post(
+                "/api/answer",
+                data=json.dumps({"question": "test"}),
+                content_type="application/json",
+            )
+            assert resp.status_code == 401
+            assert resp.get_json()["error"] == "Unauthorized"
+
+    def test_usage_exceeded_returns_error(self, answer_client, mock_stream_processor):
+
+        with patch(
+            "application.api.answer.routes.answer.AnswerResource.validate_request",
+            return_value=None,
+        ), patch(
+            "application.api.answer.routes.answer.AnswerResource.check_usage",
+        ) as mock_check:
+            with flask_app_context(answer_client):
+                mock_check.return_value = ({"error": "Usage limit exceeded"}, 429)
+
+                resp = answer_client.post(
+                    "/api/answer",
+                    data=json.dumps({"question": "test"}),
+                    content_type="application/json",
+                )
+                assert resp.status_code == 429
+
+    def test_stream_error_returns_400(self, answer_client, mock_stream_processor):
+        with patch(
+            "application.api.answer.routes.answer.AnswerResource.validate_request",
+            return_value=None,
+        ), patch(
+            "application.api.answer.routes.answer.AnswerResource.check_usage",
+            return_value=None,
+        ), patch(
+            "application.api.answer.routes.answer.AnswerResource.complete_stream",
+            return_value=iter([]),
+        ), patch(
+            "application.api.answer.routes.answer.AnswerResource.process_response_stream",
+            return_value=(None, None, None, None, None, "Stream error"),
+        ):
+            resp = answer_client.post(
+                "/api/answer",
+                data=json.dumps({"question": "test"}),
+                content_type="application/json",
+            )
+            assert resp.status_code == 400
+            assert resp.get_json()["error"] == "Stream error"
+
+    def test_exception_returns_500(self, answer_client, mock_stream_processor):
+        with patch(
+            "application.api.answer.routes.answer.AnswerResource.validate_request",
+            return_value=None,
+        ), patch(
+            "application.api.answer.routes.answer.AnswerResource.check_usage",
+            return_value=None,
+        ), patch(
+            "application.api.answer.routes.answer.AnswerResource.complete_stream",
+            side_effect=RuntimeError("unexpected"),
+        ):
+            resp = answer_client.post(
+                "/api/answer",
+                data=json.dumps({"question": "test"}),
+                content_type="application/json",
+            )
+            assert resp.status_code == 500
+            assert "error" in resp.get_json()
+
+    def test_structured_info_merged_into_result(
+        self, answer_client, mock_stream_processor
+    ):
+        conv_id = str(ObjectId())
+        with patch(
+            "application.api.answer.routes.answer.AnswerResource.validate_request",
+            return_value=None,
+        ), patch(
+            "application.api.answer.routes.answer.AnswerResource.check_usage",
+            return_value=None,
+        ), patch(
+            "application.api.answer.routes.answer.AnswerResource.complete_stream",
+            return_value=iter([]),
+        ), patch(
+            "application.api.answer.routes.answer.AnswerResource.process_response_stream",
+            return_value=(
+                conv_id,
+                '{"key": "val"}',
+                [],
+                [],
+                "",
+                None,
+                {"structured": True, "schema": {"type": "object"}},
+            ),
+        ):
+            resp = answer_client.post(
+                "/api/answer",
+                data=json.dumps({"question": "test"}),
+                content_type="application/json",
+            )
+            assert resp.status_code == 200
+            data = resp.get_json()
+            assert data["structured"] is True
+            assert data["schema"] == {"type": "object"}
+
+    def test_result_contains_all_expected_fields(
+        self, answer_client, mock_stream_processor
+    ):
+        conv_id = str(ObjectId())
+        with patch(
+            "application.api.answer.routes.answer.AnswerResource.validate_request",
+            return_value=None,
+        ), patch(
+            "application.api.answer.routes.answer.AnswerResource.check_usage",
+            return_value=None,
+        ), patch(
+            "application.api.answer.routes.answer.AnswerResource.complete_stream",
+            return_value=iter([]),
+        ), patch(
+            "application.api.answer.routes.answer.AnswerResource.process_response_stream",
+            return_value=(
+                conv_id,
+                "answer text",
+                [{"title": "src"}],
+                [{"tool": "t"}],
+                "thinking...",
+                None,
+            ),
+        ):
+            resp = answer_client.post(
+                "/api/answer",
+                data=json.dumps({"question": "test"}),
+                content_type="application/json",
+            )
+            data = resp.get_json()
+            assert data["conversation_id"] == conv_id
+            assert data["answer"] == "answer text"
+            assert data["sources"] == [{"title": "src"}]
+            assert data["tool_calls"] == [{"tool": "t"}]
+            assert data["thought"] == "thinking..."
+
+
+def flask_app_context(client):
+    """Helper to get app context from test client."""
+    return client.application.app_context()
diff --git a/tests/api/answer/routes/test_stream.py b/tests/api/answer/routes/test_stream.py
new file mode 100644
index 00000000..f025bfd0
--- /dev/null
+++ b/tests/api/answer/routes/test_stream.py
@@ -0,0 +1,195 @@
+"""Tests for application/api/answer/routes/stream.py"""
+
+import json
+from unittest.mock import MagicMock, patch
+
+import pytest
+from bson import ObjectId
+
+
+@pytest.fixture
+def mock_stream_processor():
+    """Create a mock StreamProcessor for stream tests."""
+    with patch(
+        "application.api.answer.routes.stream.StreamProcessor"
+    ) as MockProcessor:
+        processor = MagicMock()
+        processor.decoded_token = {"sub": "test_user"}
+        processor.conversation_id = str(ObjectId())
+        processor.agent_config = {}
+        processor.agent_id = str(ObjectId())
+        processor.is_shared_usage = False
+        processor.shared_token = None
+        processor.model_id = "gpt-4"
+        processor.build_agent.return_value = MagicMock()
+        MockProcessor.return_value = processor
+        yield processor
+
+
+@pytest.fixture
+def stream_client(mock_mongo_db, flask_app):
+    """Create a test client with the stream route registered."""
+    from flask_restx import Api
+
+    from application.api.answer.routes.stream import answer_ns
+
+    api = Api(flask_app)
+    api.add_namespace(answer_ns)
+    flask_app.config["TESTING"] = True
+    return flask_app.test_client()
+
+
+@pytest.mark.unit
+class TestStreamResourcePost:
+    def test_missing_question_returns_400(self, stream_client, mock_stream_processor):
+        resp = stream_client.post(
+            "/stream",
+            data=json.dumps({}),
+            content_type="application/json",
+        )
+        assert resp.status_code == 400
+
+    def test_successful_stream(self, stream_client, mock_stream_processor):
+        def fake_stream(*args, **kwargs):
+            yield f'data: {json.dumps({"type": "answer", "answer": "Hi"})}\n\n'
+            yield f'data: {json.dumps({"type": "end"})}\n\n'
+
+        with patch(
+            "application.api.answer.routes.stream.StreamResource.validate_request",
+            return_value=None,
+        ), patch(
+            "application.api.answer.routes.stream.StreamResource.check_usage",
+            return_value=None,
+        ), patch(
+            "application.api.answer.routes.stream.StreamResource.complete_stream",
+            side_effect=fake_stream,
+        ):
+            resp = stream_client.post(
+                "/stream",
+                data=json.dumps({"question": "What is Python?"}),
+                content_type="application/json",
+            )
+            assert resp.status_code == 200
+            assert "text/event-stream" in resp.content_type
+            data = resp.get_data(as_text=True)
+            assert '"type": "answer"' in data
+            assert '"answer": "Hi"' in data
+
+    def test_unauthorized_returns_401_stream(
+        self, stream_client, mock_stream_processor
+    ):
+        mock_stream_processor.decoded_token = None
+        with patch(
+            "application.api.answer.routes.stream.StreamResource.validate_request",
+            return_value=None,
+        ):
+            resp = stream_client.post(
+                "/stream",
+                data=json.dumps({"question": "test"}),
+                content_type="application/json",
+            )
+            assert resp.status_code == 401
+            assert "text/event-stream" in resp.content_type
+            data = resp.get_data(as_text=True)
+            assert "Unauthorized" in data
+
+    def test_usage_exceeded_returns_error(
+        self, stream_client, mock_stream_processor
+    ):
+        with patch(
+            "application.api.answer.routes.stream.StreamResource.validate_request",
+            return_value=None,
+        ), patch(
+            "application.api.answer.routes.stream.StreamResource.check_usage",
+        ) as mock_check:
+            mock_check.return_value = ({"error": "Usage limit exceeded"}, 429)
+            resp = stream_client.post(
+                "/stream",
+                data=json.dumps({"question": "test"}),
+                content_type="application/json",
+            )
+            assert resp.status_code == 429
+
+    def test_value_error_returns_400_stream(
+        self, stream_client, mock_stream_processor
+    ):
+        mock_stream_processor.build_agent.side_effect = ValueError("bad data")
+        with patch(
+            "application.api.answer.routes.stream.StreamResource.validate_request",
+            return_value=None,
+        ):
+            resp = stream_client.post(
+                "/stream",
+                data=json.dumps({"question": "test"}),
+                content_type="application/json",
+            )
+            assert resp.status_code == 400
+            assert "text/event-stream" in resp.content_type
+            data = resp.get_data(as_text=True)
+            assert "Malformed request body" in data
+
+    def test_general_exception_returns_400_stream(
+        self, stream_client, mock_stream_processor
+    ):
+        mock_stream_processor.build_agent.side_effect = RuntimeError("crash")
+        with patch(
+            "application.api.answer.routes.stream.StreamResource.validate_request",
+            return_value=None,
+        ):
+            resp = stream_client.post(
+                "/stream",
+                data=json.dumps({"question": "test"}),
+                content_type="application/json",
+            )
+            assert resp.status_code == 400
+            assert "text/event-stream" in resp.content_type
+            data = resp.get_data(as_text=True)
+            assert "Unknown error occurred" in data
+
+    def test_index_in_data_requires_conversation_id(
+        self, stream_client, mock_stream_processor
+    ):
+        """When 'index' is present, validate_request is called with require_conversation_id=True."""
+        resp = stream_client.post(
+            "/stream",
+            data=json.dumps({"question": "test", "index": 0}),
+            content_type="application/json",
+        )
+        # Should get 400 since conversation_id is missing
+        assert resp.status_code == 400
+
+    def test_stream_passes_attachments_and_index(
+        self, stream_client, mock_stream_processor
+    ):
+        """Verify attachments and index params are forwarded to complete_stream."""
+
+        def fake_stream(*args, **kwargs):
+            yield f'data: {json.dumps({"type": "end"})}\n\n'
+
+        conv_id = str(ObjectId())
+        with patch(
+            "application.api.answer.routes.stream.StreamResource.validate_request",
+            return_value=None,
+        ), patch(
+            "application.api.answer.routes.stream.StreamResource.check_usage",
+            return_value=None,
+        ), patch(
+            "application.api.answer.routes.stream.StreamResource.complete_stream",
+            side_effect=fake_stream,
+        ) as mock_complete:
+            resp = stream_client.post(
+                "/stream",
+                data=json.dumps(
+                    {
+                        "question": "test",
+                        "conversation_id": conv_id,
+                        "index": 3,
+                        "attachments": ["att1", "att2"],
+                    }
+                ),
+                content_type="application/json",
+            )
+            assert resp.status_code == 200
+            call_kwargs = mock_complete.call_args
+            assert call_kwargs.kwargs.get("index") == 3
+            assert call_kwargs.kwargs.get("attachment_ids") == ["att1", "att2"]
diff --git a/tests/api/answer/services/compression/__init__.py b/tests/api/answer/services/compression/__init__.py
new file mode 100644
index 00000000..e69de29b
diff --git a/tests/api/answer/services/compression/test_message_builder.py b/tests/api/answer/services/compression/test_message_builder.py
new file mode 100644
index 00000000..9cb681d4
--- /dev/null
+++ b/tests/api/answer/services/compression/test_message_builder.py
@@ -0,0 +1,303 @@
+"""Tests for application/api/answer/services/compression/message_builder.py"""
+
+
+import pytest
+
+from application.api.answer.services.compression.message_builder import MessageBuilder
+
+
+@pytest.mark.unit
+class TestBuildFromCompressedContext:
+    def test_no_compression_returns_system_only(self):
+        messages = MessageBuilder.build_from_compressed_context(
+            system_prompt="You are helpful.",
+            compressed_summary=None,
+            recent_queries=[],
+        )
+        assert len(messages) == 1
+        assert messages[0]["role"] == "system"
+        assert messages[0]["content"] == "You are helpful."
+
+    def test_with_recent_queries_no_compression(self):
+        queries = [
+            {"prompt": "Hello", "response": "Hi there!"},
+            {"prompt": "How are you?", "response": "I'm fine."},
+        ]
+        messages = MessageBuilder.build_from_compressed_context(
+            system_prompt="System prompt",
+            compressed_summary=None,
+            recent_queries=queries,
+        )
+        # system + 2 * (user + assistant) = 5
+        assert len(messages) == 5
+        assert messages[1] == {"role": "user", "content": "Hello"}
+        assert messages[2] == {"role": "assistant", "content": "Hi there!"}
+        assert messages[3] == {"role": "user", "content": "How are you?"}
+        assert messages[4] == {"role": "assistant", "content": "I'm fine."}
+
+    def test_with_compressed_summary_appended_to_system(self):
+        messages = MessageBuilder.build_from_compressed_context(
+            system_prompt="You are helpful.",
+            compressed_summary="Previous: user asked about Python.",
+            recent_queries=[{"prompt": "More?", "response": "Sure."}],
+        )
+        system_content = messages[0]["content"]
+        assert "This session is being continued" in system_content
+        assert "Previous: user asked about Python." in system_content
+
+    def test_mid_execution_context_type(self):
+        messages = MessageBuilder.build_from_compressed_context(
+            system_prompt="System",
+            compressed_summary="Summary here",
+            recent_queries=[{"prompt": "q", "response": "r"}],
+            context_type="mid_execution",
+        )
+        system_content = messages[0]["content"]
+        assert "Context window limit reached" in system_content
+
+    def test_include_tool_calls(self):
+        queries = [
+            {
+                "prompt": "Search for X",
+                "response": "Found X",
+                "tool_calls": [
+                    {
+                        "call_id": "call-1",
+                        "action_name": "search",
+                        "arguments": {"q": "X"},
+                        "result": "X found",
+                    }
+                ],
+            }
+        ]
+        messages = MessageBuilder.build_from_compressed_context(
+            system_prompt="System",
+            compressed_summary=None,
+            recent_queries=queries,
+            include_tool_calls=True,
+        )
+        # system + user + assistant + tool_call_assistant + tool_response = 5
+        assert len(messages) == 5
+        assert messages[3]["role"] == "assistant"
+        assert "function_call" in messages[3]["content"][0]
+        assert messages[4]["role"] == "tool"
+        assert "function_response" in messages[4]["content"][0]
+
+    def test_tool_calls_not_included_by_default(self):
+        queries = [
+            {
+                "prompt": "Search",
+                "response": "Found",
+                "tool_calls": [
+                    {
+                        "call_id": "c1",
+                        "action_name": "search",
+                        "arguments": {},
+                        "result": "ok",
+                    }
+                ],
+            }
+        ]
+        messages = MessageBuilder.build_from_compressed_context(
+            system_prompt="System",
+            compressed_summary=None,
+            recent_queries=queries,
+            include_tool_calls=False,
+        )
+        # system + user + assistant = 3 (no tool messages)
+        assert len(messages) == 3
+
+    def test_tool_call_without_call_id_generates_uuid(self):
+        queries = [
+            {
+                "prompt": "q",
+                "response": "r",
+                "tool_calls": [
+                    {
+                        "action_name": "act",
+                        "arguments": {},
+                        "result": "res",
+                    }
+                ],
+            }
+        ]
+        messages = MessageBuilder.build_from_compressed_context(
+            system_prompt="S",
+            compressed_summary=None,
+            recent_queries=queries,
+            include_tool_calls=True,
+        )
+        tool_msg = messages[3]["content"][0]
+        call_id = tool_msg["function_call"]["call_id"]
+        assert call_id is not None
+        assert len(call_id) > 0
+
+    def test_continuation_message_when_no_recent_queries_but_has_summary(self):
+        messages = MessageBuilder.build_from_compressed_context(
+            system_prompt="System",
+            compressed_summary="Everything was compressed",
+            recent_queries=[],
+        )
+        # system + continuation user message = 2
+        assert len(messages) == 2
+        assert messages[1]["role"] == "user"
+        assert "continue" in messages[1]["content"].lower()
+
+    def test_no_continuation_when_no_summary(self):
+        messages = MessageBuilder.build_from_compressed_context(
+            system_prompt="System",
+            compressed_summary=None,
+            recent_queries=[],
+        )
+        assert len(messages) == 1
+
+    def test_queries_without_prompt_or_response_skipped(self):
+        queries = [
+            {"other_field": "value"},
+            {"prompt": "real", "response": "answer"},
+        ]
+        messages = MessageBuilder.build_from_compressed_context(
+            system_prompt="S",
+            compressed_summary=None,
+            recent_queries=queries,
+        )
+        # system + 1 valid query (user + assistant) = 3
+        assert len(messages) == 3
+
+
+@pytest.mark.unit
+class TestAppendCompressionContext:
+    def test_pre_request_context(self):
+        result = MessageBuilder._append_compression_context(
+            "Original prompt", "Summary text", "pre_request"
+        )
+        assert "This session is being continued" in result
+        assert "Summary text" in result
+        assert result.startswith("Original prompt")
+
+    def test_mid_execution_context(self):
+        result = MessageBuilder._append_compression_context(
+            "Original prompt", "Summary text", "mid_execution"
+        )
+        assert "Context window limit reached" in result
+        assert "Summary text" in result
+
+    def test_removes_existing_compression_context(self):
+        prompt_with_existing = (
+            "Original prompt\n\n---\n\nThis session is being continued from old"
+        )
+        result = MessageBuilder._append_compression_context(
+            prompt_with_existing, "New summary", "pre_request"
+        )
+        # Should not contain old context twice
+        assert result.count("This session is being continued") == 1
+        assert "New summary" in result
+
+    def test_removes_mid_execution_context(self):
+        prompt_with_existing = (
+            "Original\n\n---\n\nContext window limit reached during execution. Old."
+        )
+        result = MessageBuilder._append_compression_context(
+            prompt_with_existing, "New", "mid_execution"
+        )
+        assert result.count("Context window limit reached") == 1
+
+
+@pytest.mark.unit
+class TestRebuildMessagesAfterCompression:
+    def test_basic_rebuild(self):
+        messages = [
+            {"role": "system", "content": "You are helpful."},
+            {"role": "user", "content": "old message"},
+            {"role": "assistant", "content": "old reply"},
+        ]
+        recent = [{"prompt": "new q", "response": "new r"}]
+
+        result = MessageBuilder.rebuild_messages_after_compression(
+            messages=messages,
+            compressed_summary="Everything was compressed.",
+            recent_queries=recent,
+        )
+        assert result is not None
+        # system + user + assistant = 3
+        assert len(result) == 3
+        assert "Context window limit reached" in result[0]["content"]
+        assert result[1] == {"role": "user", "content": "new q"}
+        assert result[2] == {"role": "assistant", "content": "new r"}
+
+    def test_returns_none_without_system_message(self):
+        messages = [
+            {"role": "user", "content": "hello"},
+        ]
+        result = MessageBuilder.rebuild_messages_after_compression(
+            messages=messages,
+            compressed_summary="summary",
+            recent_queries=[],
+        )
+        assert result is None
+
+    def test_no_summary_keeps_system_unchanged(self):
+        messages = [{"role": "system", "content": "Be helpful."}]
+        result = MessageBuilder.rebuild_messages_after_compression(
+            messages=messages,
+            compressed_summary=None,
+            recent_queries=[],
+        )
+        assert result is not None
+        assert result[0]["content"] == "Be helpful."
+
+    def test_include_tool_calls_in_rebuild(self):
+        messages = [{"role": "system", "content": "S"}]
+        recent = [
+            {
+                "prompt": "q",
+                "response": "r",
+                "tool_calls": [
+                    {
+                        "call_id": "c1",
+                        "action_name": "act",
+                        "arguments": {"a": 1},
+                        "result": "done",
+                    }
+                ],
+            }
+        ]
+        result = MessageBuilder.rebuild_messages_after_compression(
+            messages=messages,
+            compressed_summary="s",
+            recent_queries=recent,
+            include_tool_calls=True,
+        )
+        # system + user + assistant + tool_call + tool_response = 5
+        assert len(result) == 5
+
+    def test_continuation_added_when_no_recent_queries(self):
+        messages = [{"role": "system", "content": "S"}]
+        result = MessageBuilder.rebuild_messages_after_compression(
+            messages=messages,
+            compressed_summary="All compressed",
+            recent_queries=[],
+        )
+        assert len(result) == 2
+        assert result[1]["role"] == "user"
+        assert "continue" in result[1]["content"].lower()
+
+    def test_include_current_execution_preserves_extra_messages(self):
+        messages = [
+            {"role": "system", "content": "S"},
+            {"role": "user", "content": "q1"},
+            {"role": "assistant", "content": "r1"},
+            {"role": "user", "content": "current execution msg"},
+        ]
+        recent = [{"prompt": "q1", "response": "r1"}]
+
+        result = MessageBuilder.rebuild_messages_after_compression(
+            messages=messages,
+            compressed_summary="summary",
+            recent_queries=recent,
+            include_current_execution=True,
+        )
+        assert result is not None
+        # Should include the current execution message
+        contents = [m.get("content") for m in result]
+        assert "current execution msg" in contents
diff --git a/tests/api/answer/services/compression/test_orchestrator.py b/tests/api/answer/services/compression/test_orchestrator.py
new file mode 100644
index 00000000..67701614
--- /dev/null
+++ b/tests/api/answer/services/compression/test_orchestrator.py
@@ -0,0 +1,447 @@
+"""Tests for application/api/answer/services/compression/orchestrator.py"""
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from application.api.answer.services.compression.orchestrator import (
+    CompressionOrchestrator,
+)
+from application.api.answer.services.compression.types import (
+    CompressionMetadata,
+    CompressionResult,
+)
+
+
+@pytest.fixture
+def mock_conversation_service():
+    svc = MagicMock()
+    return svc
+
+
+@pytest.fixture
+def mock_threshold_checker():
+    checker = MagicMock()
+    return checker
+
+
+@pytest.fixture
+def orchestrator(mock_conversation_service, mock_threshold_checker):
+    return CompressionOrchestrator(
+        conversation_service=mock_conversation_service,
+        threshold_checker=mock_threshold_checker,
+    )
+
+
+@pytest.fixture
+def sample_conversation():
+    return {
+        "queries": [
+            {"prompt": "q0", "response": "r0"},
+            {"prompt": "q1", "response": "r1"},
+            {"prompt": "q2", "response": "r2"},
+        ],
+        "compression_metadata": {},
+        "agent_id": "agent-1",
+    }
+
+
+@pytest.fixture
+def decoded_token():
+    return {"sub": "user123"}
+
+
+@pytest.mark.unit
+class TestCompressIfNeeded:
+    def test_conversation_not_found_returns_failure(
+        self, orchestrator, mock_conversation_service
+    ):
+        mock_conversation_service.get_conversation.return_value = None
+
+        result = orchestrator.compress_if_needed(
+            conversation_id="conv1",
+            user_id="user1",
+            model_id="gpt-4",
+            decoded_token={"sub": "user1"},
+        )
+
+        assert result.success is False
+        assert "not found" in result.error
+
+    def test_no_compression_needed(
+        self,
+        orchestrator,
+        mock_conversation_service,
+        mock_threshold_checker,
+        sample_conversation,
+    ):
+        mock_conversation_service.get_conversation.return_value = sample_conversation
+        mock_threshold_checker.should_compress.return_value = False
+
+        result = orchestrator.compress_if_needed(
+            conversation_id="conv1",
+            user_id="user1",
+            model_id="gpt-4",
+            decoded_token={"sub": "user1"},
+        )
+
+        assert result.success is True
+        assert result.compression_performed is False
+        assert len(result.recent_queries) == 3
+
+    def test_compression_performed_successfully(
+        self,
+        orchestrator,
+        mock_conversation_service,
+        mock_threshold_checker,
+        sample_conversation,
+        decoded_token,
+    ):
+        mock_conversation_service.get_conversation.return_value = sample_conversation
+        mock_threshold_checker.should_compress.return_value = True
+
+        mock_metadata = MagicMock(spec=CompressionMetadata)
+        mock_metadata.compression_ratio = 5.0
+        mock_metadata.original_token_count = 1000
+        mock_metadata.compressed_token_count = 200
+        mock_metadata.to_dict.return_value = {"query_index": 2}
+
+        with patch.object(
+            orchestrator, "_perform_compression"
+        ) as mock_perform:
+            mock_perform.return_value = CompressionResult.success_with_compression(
+                "compressed summary",
+                [{"prompt": "q2", "response": "r2"}],
+                mock_metadata,
+            )
+
+            result = orchestrator.compress_if_needed(
+                conversation_id="conv1",
+                user_id="user1",
+                model_id="gpt-4",
+                decoded_token=decoded_token,
+            )
+
+            assert result.success is True
+            assert result.compression_performed is True
+            assert result.compressed_summary == "compressed summary"
+            mock_perform.assert_called_once()
+
+    def test_exception_returns_failure(
+        self,
+        orchestrator,
+        mock_conversation_service,
+    ):
+        mock_conversation_service.get_conversation.side_effect = RuntimeError("DB down")
+
+        result = orchestrator.compress_if_needed(
+            conversation_id="conv1",
+            user_id="user1",
+            model_id="gpt-4",
+            decoded_token={"sub": "user1"},
+        )
+
+        assert result.success is False
+        assert "DB down" in result.error
+
+    def test_custom_query_tokens(
+        self,
+        orchestrator,
+        mock_conversation_service,
+        mock_threshold_checker,
+        sample_conversation,
+    ):
+        mock_conversation_service.get_conversation.return_value = sample_conversation
+        mock_threshold_checker.should_compress.return_value = False
+
+        orchestrator.compress_if_needed(
+            conversation_id="conv1",
+            user_id="user1",
+            model_id="gpt-4",
+            decoded_token={"sub": "user1"},
+            current_query_tokens=1000,
+        )
+
+        mock_threshold_checker.should_compress.assert_called_once_with(
+            sample_conversation, "gpt-4", 1000
+        )
+
+
+@pytest.mark.unit
+class TestPerformCompression:
+    @patch(
+        "application.api.answer.services.compression.orchestrator.get_provider_from_model_id"
+    )
+    @patch(
+        "application.api.answer.services.compression.orchestrator.get_api_key_for_provider"
+    )
+    @patch("application.api.answer.services.compression.orchestrator.LLMCreator")
+    @patch("application.api.answer.services.compression.orchestrator.CompressionService")
+    @patch("application.api.answer.services.compression.orchestrator.settings")
+    def test_successful_compression(
+        self,
+        mock_settings,
+        MockCompressionService,
+        MockLLMCreator,
+        mock_get_api_key,
+        mock_get_provider,
+        mock_conversation_service,
+        mock_threshold_checker,
+        sample_conversation,
+        decoded_token,
+    ):
+        mock_settings.COMPRESSION_MODEL_OVERRIDE = None
+        mock_get_provider.return_value = "openai"
+        mock_get_api_key.return_value = "sk-test"
+        MockLLMCreator.create_llm.return_value = MagicMock()
+
+        mock_metadata = MagicMock(spec=CompressionMetadata)
+        mock_metadata.compression_ratio = 5.0
+        mock_metadata.original_token_count = 500
+        mock_metadata.compressed_token_count = 100
+
+        mock_svc_instance = MagicMock()
+        mock_svc_instance.compress_and_save.return_value = mock_metadata
+        mock_svc_instance.get_compressed_context.return_value = (
+            "compressed text",
+            [{"prompt": "q2", "response": "r2"}],
+        )
+        MockCompressionService.return_value = mock_svc_instance
+
+        # After compression, reload conversation
+        mock_conversation_service.get_conversation.return_value = sample_conversation
+
+        orch = CompressionOrchestrator(
+            conversation_service=mock_conversation_service,
+            threshold_checker=mock_threshold_checker,
+        )
+
+        result = orch._perform_compression(
+            "conv1", sample_conversation, "gpt-4", decoded_token
+        )
+
+        assert result.success is True
+        assert result.compression_performed is True
+        assert result.compressed_summary == "compressed text"
+        mock_svc_instance.compress_and_save.assert_called_once()
+
+    @patch(
+        "application.api.answer.services.compression.orchestrator.get_provider_from_model_id"
+    )
+    @patch(
+        "application.api.answer.services.compression.orchestrator.get_api_key_for_provider"
+    )
+    @patch("application.api.answer.services.compression.orchestrator.LLMCreator")
+    @patch("application.api.answer.services.compression.orchestrator.settings")
+    def test_uses_compression_model_override(
+        self,
+        mock_settings,
+        MockLLMCreator,
+        mock_get_api_key,
+        mock_get_provider,
+        mock_conversation_service,
+        mock_threshold_checker,
+        decoded_token,
+    ):
+        mock_settings.COMPRESSION_MODEL_OVERRIDE = "gpt-3.5-turbo"
+        mock_get_provider.return_value = "openai"
+        mock_get_api_key.return_value = "sk-test"
+        MockLLMCreator.create_llm.return_value = MagicMock()
+
+        conversation = {"queries": [{"prompt": "q", "response": "r"}], "agent_id": "a"}
+
+        with patch(
+            "application.api.answer.services.compression.orchestrator.CompressionService"
+        ) as MockCS:
+            mock_svc = MagicMock()
+            mock_svc.compress_and_save.return_value = MagicMock(
+                compression_ratio=3.0,
+                original_token_count=300,
+                compressed_token_count=100,
+            )
+            mock_svc.get_compressed_context.return_value = ("s", [])
+            MockCS.return_value = mock_svc
+
+            mock_conversation_service.get_conversation.return_value = conversation
+
+            orch = CompressionOrchestrator(
+                conversation_service=mock_conversation_service,
+                threshold_checker=mock_threshold_checker,
+            )
+            orch._perform_compression("c1", conversation, "gpt-4", decoded_token)
+
+            # Verify the override model was used
+            mock_get_provider.assert_called_with("gpt-3.5-turbo")
+
+    @patch(
+        "application.api.answer.services.compression.orchestrator.get_provider_from_model_id"
+    )
+    @patch(
+        "application.api.answer.services.compression.orchestrator.get_api_key_for_provider"
+    )
+    @patch("application.api.answer.services.compression.orchestrator.LLMCreator")
+    @patch("application.api.answer.services.compression.orchestrator.CompressionService")
+    @patch("application.api.answer.services.compression.orchestrator.settings")
+    def test_no_queries_returns_no_compression(
+        self,
+        mock_settings,
+        MockCompressionService,
+        MockLLMCreator,
+        mock_get_api_key,
+        mock_get_provider,
+        mock_conversation_service,
+        mock_threshold_checker,
+        decoded_token,
+    ):
+        mock_settings.COMPRESSION_MODEL_OVERRIDE = None
+        mock_get_provider.return_value = "openai"
+        mock_get_api_key.return_value = "sk-test"
+        MockLLMCreator.create_llm.return_value = MagicMock()
+
+        conversation = {"queries": [], "agent_id": "a"}
+
+        orch = CompressionOrchestrator(
+            conversation_service=mock_conversation_service,
+            threshold_checker=mock_threshold_checker,
+        )
+        result = orch._perform_compression("c1", conversation, "gpt-4", decoded_token)
+
+        assert result.success is True
+        assert result.compression_performed is False
+
+    def test_exception_returns_failure(
+        self,
+        mock_conversation_service,
+        mock_threshold_checker,
+        decoded_token,
+    ):
+        conversation = {
+            "queries": [{"prompt": "q", "response": "r"}],
+            "agent_id": "a",
+        }
+
+        with patch(
+            "application.api.answer.services.compression.orchestrator.settings"
+        ) as mock_settings, patch(
+            "application.api.answer.services.compression.orchestrator.get_provider_from_model_id",
+            side_effect=RuntimeError("provider error"),
+        ):
+            mock_settings.COMPRESSION_MODEL_OVERRIDE = None
+
+            orch = CompressionOrchestrator(
+                conversation_service=mock_conversation_service,
+                threshold_checker=mock_threshold_checker,
+            )
+            result = orch._perform_compression(
+                "c1", conversation, "gpt-4", decoded_token
+            )
+
+            assert result.success is False
+            assert "provider error" in result.error
+
+
+@pytest.mark.unit
+class TestCompressMidExecution:
+    def test_with_provided_conversation(
+        self,
+        orchestrator,
+        sample_conversation,
+        decoded_token,
+    ):
+        with patch.object(
+            orchestrator, "_perform_compression"
+        ) as mock_perform:
+            mock_perform.return_value = CompressionResult.success_no_compression([])
+
+            orchestrator.compress_mid_execution(
+                conversation_id="conv1",
+                user_id="user1",
+                model_id="gpt-4",
+                decoded_token=decoded_token,
+                current_conversation=sample_conversation,
+            )
+
+            mock_perform.assert_called_once_with(
+                "conv1", sample_conversation, "gpt-4", decoded_token
+            )
+
+    def test_loads_conversation_when_not_provided(
+        self,
+        orchestrator,
+        mock_conversation_service,
+        sample_conversation,
+        decoded_token,
+    ):
+        mock_conversation_service.get_conversation.return_value = sample_conversation
+
+        with patch.object(
+            orchestrator, "_perform_compression"
+        ) as mock_perform:
+            mock_perform.return_value = CompressionResult.success_no_compression([])
+
+            orchestrator.compress_mid_execution(
+                conversation_id="conv1",
+                user_id="user1",
+                model_id="gpt-4",
+                decoded_token=decoded_token,
+            )
+
+            mock_conversation_service.get_conversation.assert_called_once_with(
+                "conv1", "user1"
+            )
+            mock_perform.assert_called_once()
+
+    def test_conversation_not_found_returns_failure(
+        self,
+        orchestrator,
+        mock_conversation_service,
+        decoded_token,
+    ):
+        mock_conversation_service.get_conversation.return_value = None
+
+        result = orchestrator.compress_mid_execution(
+            conversation_id="conv1",
+            user_id="user1",
+            model_id="gpt-4",
+            decoded_token=decoded_token,
+        )
+
+        assert result.success is False
+        assert "not found" in result.error
+
+    def test_exception_returns_failure(
+        self,
+        orchestrator,
+        mock_conversation_service,
+        decoded_token,
+    ):
+        mock_conversation_service.get_conversation.side_effect = RuntimeError("fail")
+
+        result = orchestrator.compress_mid_execution(
+            conversation_id="conv1",
+            user_id="user1",
+            model_id="gpt-4",
+            decoded_token=decoded_token,
+        )
+
+        assert result.success is False
+        assert "fail" in result.error
+
+
+@pytest.mark.unit
+class TestOrchestratorInit:
+    def test_default_threshold_checker(self, mock_conversation_service):
+        orch = CompressionOrchestrator(
+            conversation_service=mock_conversation_service
+        )
+        assert orch.threshold_checker is not None
+        assert orch.conversation_service is mock_conversation_service
+
+    def test_custom_threshold_checker(
+        self, mock_conversation_service, mock_threshold_checker
+    ):
+        orch = CompressionOrchestrator(
+            conversation_service=mock_conversation_service,
+            threshold_checker=mock_threshold_checker,
+        )
+        assert orch.threshold_checker is mock_threshold_checker
diff --git a/tests/api/answer/services/compression/test_service.py b/tests/api/answer/services/compression/test_service.py
new file mode 100644
index 00000000..99042780
--- /dev/null
+++ b/tests/api/answer/services/compression/test_service.py
@@ -0,0 +1,423 @@
+"""Tests for application/api/answer/services/compression/service.py"""
+
+from unittest.mock import MagicMock, patch
+
+import pytest
+
+from application.api.answer.services.compression.service import CompressionService
+from application.api.answer.services.compression.types import CompressionMetadata
+
+
+@pytest.fixture
+def mock_llm():
+    llm = MagicMock()
+    llm.gen.return_value = "<summary>Compressed summary content</summary>"
+    return llm
+
+
+@pytest.fixture
+def mock_conversation_service():
+    svc = MagicMock()
+    svc.update_compression_metadata = MagicMock()
+    return svc
+
+
+@pytest.fixture
+def sample_conversation():
+    return {
+        "queries": [
+            {"prompt": "What is Python?", "response": "A programming language."},
+            {"prompt": "Tell me more.", "response": "It's versatile and popular."},
+            {
+                "prompt": "What about tools?",
+                "response": "Python has many tools.",
+                "tool_calls": [
+                    {
+                        "tool_name": "search",
+                        "action_name": "web_search",
+                        "arguments": {"q": "python tools"},
+                        "result": "Found 10 results",
+                        "status": "success",
+                    }
+                ],
+            },
+        ],
+        "compression_metadata": {},
+    }
+
+
+@pytest.mark.unit
+class TestCompressionServiceInit:
+    @patch("application.api.answer.services.compression.service.settings")
+    def test_default_prompt_builder(self, mock_settings, mock_llm):
+        mock_settings.COMPRESSION_PROMPT_VERSION = "v1.0"
+        with patch(
+            "application.api.answer.services.compression.service.CompressionPromptBuilder"
+        ):
+            svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+            assert svc.llm is mock_llm
+            assert svc.model_id == "gpt-4"
+
+    def test_custom_prompt_builder(self, mock_llm):
+        custom_builder = MagicMock()
+        svc = CompressionService(
+            llm=mock_llm, model_id="gpt-4", prompt_builder=custom_builder
+        )
+        assert svc.prompt_builder is custom_builder
+
+
+@pytest.mark.unit
+class TestCompressConversation:
+    def test_successful_compression(self, mock_llm, sample_conversation):
+        mock_builder = MagicMock()
+        mock_builder.build_prompt.return_value = [
+            {"role": "system", "content": "Compress"},
+            {"role": "user", "content": "Conversation..."},
+        ]
+        mock_builder.version = "v1.0"
+
+        svc = CompressionService(
+            llm=mock_llm, model_id="gpt-4", prompt_builder=mock_builder
+        )
+
+        with patch(
+            "application.api.answer.services.compression.service.TokenCounter"
+        ) as MockTC:
+            MockTC.count_query_tokens.return_value = 1000
+            MockTC.count_message_tokens.return_value = 100
+
+            result = svc.compress_conversation(sample_conversation, 2)
+
+            assert isinstance(result, CompressionMetadata)
+            assert result.query_index == 2
+            assert result.compressed_summary == "Compressed summary content"
+            assert result.original_token_count == 1000
+            assert result.compressed_token_count == 100
+            assert result.compression_ratio == 10.0
+            assert result.model_used == "gpt-4"
+            assert result.compression_prompt_version == "v1.0"
+
+    def test_invalid_index_negative(self, mock_llm, sample_conversation):
+        mock_builder = MagicMock()
+        mock_builder.version = "v1.0"
+        svc = CompressionService(
+            llm=mock_llm, model_id="gpt-4", prompt_builder=mock_builder
+        )
+
+        with pytest.raises(ValueError, match="Invalid compress_up_to_index"):
+            svc.compress_conversation(sample_conversation, -1)
+
+    def test_invalid_index_too_large(self, mock_llm, sample_conversation):
+        mock_builder = MagicMock()
+        mock_builder.version = "v1.0"
+        svc = CompressionService(
+            llm=mock_llm, model_id="gpt-4", prompt_builder=mock_builder
+        )
+
+        with pytest.raises(ValueError, match="Invalid compress_up_to_index"):
+            svc.compress_conversation(sample_conversation, 10)
+
+    def test_with_existing_compressions(self, mock_llm):
+        conversation = {
+            "queries": [
+                {"prompt": "q1", "response": "r1"},
+                {"prompt": "q2", "response": "r2"},
+            ],
+            "compression_metadata": {
+                "compression_points": [
+                    {
+                        "query_index": 0,
+                        "compressed_summary": "Previous summary",
+                    }
+                ]
+            },
+        }
+        mock_builder = MagicMock()
+        mock_builder.build_prompt.return_value = [
+            {"role": "system", "content": "Compress"},
+            {"role": "user", "content": "..."},
+        ]
+        mock_builder.version = "v1.0"
+
+        svc = CompressionService(
+            llm=mock_llm, model_id="gpt-4", prompt_builder=mock_builder
+        )
+
+        with patch(
+            "application.api.answer.services.compression.service.TokenCounter"
+        ) as MockTC:
+            MockTC.count_query_tokens.return_value = 500
+            MockTC.count_message_tokens.return_value = 50
+
+            result = svc.compress_conversation(conversation, 1)
+            assert isinstance(result, CompressionMetadata)
+            # Verify existing compressions were passed to prompt builder
+            call_args = mock_builder.build_prompt.call_args
+            assert call_args[0][1] == [
+                {"query_index": 0, "compressed_summary": "Previous summary"}
+            ]
+
+    def test_zero_compressed_tokens_ratio(self, mock_llm, sample_conversation):
+        mock_builder = MagicMock()
+        mock_builder.build_prompt.return_value = [
+            {"role": "system", "content": "C"},
+            {"role": "user", "content": "..."},
+        ]
+        mock_builder.version = "v1.0"
+
+        svc = CompressionService(
+            llm=mock_llm, model_id="gpt-4", prompt_builder=mock_builder
+        )
+
+        with patch(
+            "application.api.answer.services.compression.service.TokenCounter"
+        ) as MockTC:
+            MockTC.count_query_tokens.return_value = 1000
+            MockTC.count_message_tokens.return_value = 0
+
+            result = svc.compress_conversation(sample_conversation, 2)
+            assert result.compression_ratio == 0
+
+    def test_llm_error_propagates(self, sample_conversation):
+        llm = MagicMock()
+        llm.gen.side_effect = RuntimeError("LLM error")
+        mock_builder = MagicMock()
+        mock_builder.build_prompt.return_value = [
+            {"role": "system", "content": "C"},
+            {"role": "user", "content": "..."},
+        ]
+        mock_builder.version = "v1.0"
+
+        svc = CompressionService(
+            llm=llm, model_id="gpt-4", prompt_builder=mock_builder
+        )
+
+        with patch(
+            "application.api.answer.services.compression.service.TokenCounter"
+        ) as MockTC:
+            MockTC.count_query_tokens.return_value = 100
+            with pytest.raises(RuntimeError, match="LLM error"):
+                svc.compress_conversation(sample_conversation, 2)
+
+
+@pytest.mark.unit
+class TestCompressAndSave:
+    def test_saves_metadata_to_db(
+        self, mock_llm, mock_conversation_service, sample_conversation
+    ):
+        mock_builder = MagicMock()
+        mock_builder.build_prompt.return_value = [
+            {"role": "system", "content": "C"},
+            {"role": "user", "content": "..."},
+        ]
+        mock_builder.version = "v1.0"
+
+        svc = CompressionService(
+            llm=mock_llm,
+            model_id="gpt-4",
+            conversation_service=mock_conversation_service,
+            prompt_builder=mock_builder,
+        )
+
+        with patch(
+            "application.api.answer.services.compression.service.TokenCounter"
+        ) as MockTC:
+            MockTC.count_query_tokens.return_value = 500
+            MockTC.count_message_tokens.return_value = 50
+
+            result = svc.compress_and_save("conv_123", sample_conversation, 2)
+
+            assert isinstance(result, CompressionMetadata)
+            mock_conversation_service.update_compression_metadata.assert_called_once_with(
+                "conv_123", result.to_dict()
+            )
+
+    def test_raises_without_conversation_service(self, mock_llm, sample_conversation):
+        mock_builder = MagicMock()
+        mock_builder.version = "v1.0"
+        svc = CompressionService(
+            llm=mock_llm, model_id="gpt-4", prompt_builder=mock_builder
+        )
+
+        with pytest.raises(ValueError, match="conversation_service required"):
+            svc.compress_and_save("conv_123", sample_conversation, 2)
+
+
+@pytest.mark.unit
+class TestGetCompressedContext:
+    def test_no_compression_returns_full_history(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        conversation = {
+            "queries": [{"prompt": "q1", "response": "r1"}],
+            "compression_metadata": {},
+        }
+
+        summary, queries = svc.get_compressed_context(conversation)
+
+        assert summary is None
+        assert queries == [{"prompt": "q1", "response": "r1"}]
+
+    def test_no_compression_points_returns_full_history(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        conversation = {
+            "queries": [{"prompt": "q1", "response": "r1"}],
+            "compression_metadata": {"is_compressed": True, "compression_points": []},
+        }
+
+        summary, queries = svc.get_compressed_context(conversation)
+        assert summary is None
+        assert len(queries) == 1
+
+    def test_with_compression_returns_summary_and_recent(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        conversation = {
+            "queries": [
+                {"prompt": "q0", "response": "r0"},
+                {"prompt": "q1", "response": "r1"},
+                {"prompt": "q2", "response": "r2"},
+            ],
+            "compression_metadata": {
+                "is_compressed": True,
+                "compression_points": [
+                    {
+                        "query_index": 1,
+                        "compressed_summary": "Summary of q0 and q1",
+                        "compressed_token_count": 50,
+                        "original_token_count": 500,
+                    }
+                ],
+            },
+        }
+
+        summary, queries = svc.get_compressed_context(conversation)
+
+        assert summary == "Summary of q0 and q1"
+        assert len(queries) == 1
+        assert queries[0]["prompt"] == "q2"
+
+    def test_none_queries_returns_empty(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        conversation = {
+            "queries": None,
+            "compression_metadata": {},
+        }
+
+        summary, queries = svc.get_compressed_context(conversation)
+        assert summary is None
+        assert queries == []
+
+    def test_exception_falls_back_to_full_history(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        conversation = {
+            "queries": [{"prompt": "q", "response": "r"}],
+            "compression_metadata": {
+                "is_compressed": True,
+                "compression_points": "invalid",  # This will cause an error
+            },
+        }
+
+        summary, queries = svc.get_compressed_context(conversation)
+        assert summary is None
+        assert queries == [{"prompt": "q", "response": "r"}]
+
+    def test_exception_with_none_queries_returns_empty(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        # Force exception by making compression_points non-iterable
+        conversation = {
+            "queries": None,
+            "compression_metadata": {
+                "is_compressed": True,
+                "compression_points": "bad",
+            },
+        }
+
+        summary, queries = svc.get_compressed_context(conversation)
+        assert summary is None
+        assert queries == []
+
+
+@pytest.mark.unit
+class TestExtractSummary:
+    def test_extracts_from_summary_tags(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        response = "<analysis>Some analysis</analysis><summary>The actual summary</summary>"
+        result = svc._extract_summary(response)
+        assert result == "The actual summary"
+
+    def test_removes_analysis_tags_when_no_summary(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        response = "<analysis>analysis text</analysis>Raw summary text here"
+        result = svc._extract_summary(response)
+        assert result == "Raw summary text here"
+
+    def test_returns_full_response_when_no_tags(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        response = "Just a plain text response"
+        result = svc._extract_summary(response)
+        assert result == "Just a plain text response"
+
+    def test_multiline_summary(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        response = "<summary>Line 1\nLine 2\nLine 3</summary>"
+        result = svc._extract_summary(response)
+        assert "Line 1" in result
+        assert "Line 3" in result
+
+    def test_strips_whitespace(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        response = "<summary>  Trimmed  </summary>"
+        result = svc._extract_summary(response)
+        assert result == "Trimmed"
+
+
+@pytest.mark.unit
+class TestLogToolCallStats:
+    def test_no_tool_calls(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        queries = [{"prompt": "q", "response": "r"}]
+        # Should not raise
+        svc._log_tool_call_stats(queries)
+
+    def test_with_tool_calls(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        queries = [
+            {
+                "prompt": "q",
+                "response": "r",
+                "tool_calls": [
+                    {
+                        "tool_name": "search",
+                        "action_name": "web",
+                        "result": "result text",
+                    },
+                    {
+                        "tool_name": "search",
+                        "action_name": "web",
+                        "result": "more text",
+                    },
+                ],
+            }
+        ]
+        # Should not raise - just logs
+        svc._log_tool_call_stats(queries)
+
+    def test_empty_queries(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        svc._log_tool_call_stats([])
+
+    def test_tool_call_with_none_result(self, mock_llm):
+        svc = CompressionService(llm=mock_llm, model_id="gpt-4")
+        queries = [
+            {
+                "prompt": "q",
+                "response": "r",
+                "tool_calls": [
+                    {
+                        "tool_name": "t",
+                        "action_name": "a",
+                        "result": None,
+                    }
+                ],
+            }
+        ]
+        svc._log_tool_call_stats(queries)
diff --git a/tests/api/answer/services/compression/test_types.py b/tests/api/answer/services/compression/test_types.py
new file mode 100644
index 00000000..ef7a2396
--- /dev/null
+++ b/tests/api/answer/services/compression/test_types.py
@@ -0,0 +1,131 @@
+"""Tests for application/api/answer/services/compression/types.py"""
+
+from datetime import datetime, timezone
+
+import pytest
+
+from application.api.answer.services.compression.types import (
+    CompressionMetadata,
+    CompressionResult,
+)
+
+
+@pytest.mark.unit
+class TestCompressionMetadata:
+    def _make_metadata(self, **overrides):
+        defaults = dict(
+            timestamp=datetime(2025, 1, 1, tzinfo=timezone.utc),
+            query_index=5,
+            compressed_summary="Summary of conversation",
+            original_token_count=5000,
+            compressed_token_count=500,
+            compression_ratio=10.0,
+            model_used="gpt-4",
+            compression_prompt_version="v1.0",
+        )
+        defaults.update(overrides)
+        return CompressionMetadata(**defaults)
+
+    def test_to_dict_contains_all_fields(self):
+        meta = self._make_metadata()
+        d = meta.to_dict()
+
+        assert d["timestamp"] == datetime(2025, 1, 1, tzinfo=timezone.utc)
+        assert d["query_index"] == 5
+        assert d["compressed_summary"] == "Summary of conversation"
+        assert d["original_token_count"] == 5000
+        assert d["compressed_token_count"] == 500
+        assert d["compression_ratio"] == 10.0
+        assert d["model_used"] == "gpt-4"
+        assert d["compression_prompt_version"] == "v1.0"
+
+    def test_to_dict_returns_dict_type(self):
+        meta = self._make_metadata()
+        assert isinstance(meta.to_dict(), dict)
+
+    def test_to_dict_field_count(self):
+        meta = self._make_metadata()
+        d = meta.to_dict()
+        assert len(d) == 8
+
+    def test_attributes_accessible(self):
+        meta = self._make_metadata(query_index=10, compression_ratio=5.5)
+        assert meta.query_index == 10
+        assert meta.compression_ratio == 5.5
+
+    def test_zero_compressed_tokens(self):
+        meta = self._make_metadata(compressed_token_count=0, compression_ratio=0)
+        d = meta.to_dict()
+        assert d["compressed_token_count"] == 0
+        assert d["compression_ratio"] == 0
+
+
+@pytest.mark.unit
+class TestCompressionResult:
+    def test_success_with_compression(self):
+        meta = CompressionMetadata(
+            timestamp=datetime.now(timezone.utc),
+            query_index=3,
+            compressed_summary="summary",
+            original_token_count=1000,
+            compressed_token_count=100,
+            compression_ratio=10.0,
+            model_used="gpt-4",
+            compression_prompt_version="v1.0",
+        )
+        queries = [{"prompt": "q1", "response": "r1"}]
+        result = CompressionResult.success_with_compression("summary", queries, meta)
+
+        assert result.success is True
+        assert result.compressed_summary == "summary"
+        assert result.recent_queries == queries
+        assert result.metadata is meta
+        assert result.compression_performed is True
+        assert result.error is None
+
+    def test_success_no_compression(self):
+        queries = [{"prompt": "q1", "response": "r1"}]
+        result = CompressionResult.success_no_compression(queries)
+
+        assert result.success is True
+        assert result.compressed_summary is None
+        assert result.recent_queries == queries
+        assert result.metadata is None
+        assert result.compression_performed is False
+        assert result.error is None
+
+    def test_failure(self):
+        result = CompressionResult.failure("something went wrong")
+
+        assert result.success is False
+        assert result.error == "something went wrong"
+        assert result.compression_performed is False
+        assert result.compressed_summary is None
+        assert result.recent_queries == []
+        assert result.metadata is None
+
+    def test_as_history_extracts_prompt_response(self):
+        queries = [
+            {"prompt": "Hello", "response": "Hi", "extra": "ignored"},
+            {"prompt": "How?", "response": "Fine"},
+        ]
+        result = CompressionResult.success_no_compression(queries)
+        history = result.as_history()
+
+        assert len(history) == 2
+        assert history[0] == {"prompt": "Hello", "response": "Hi"}
+        assert history[1] == {"prompt": "How?", "response": "Fine"}
+
+    def test_as_history_empty_queries(self):
+        result = CompressionResult.success_no_compression([])
+        assert result.as_history() == []
+
+    def test_default_recent_queries_is_empty_list(self):
+        result = CompressionResult(success=True)
+        assert result.recent_queries == []
+        assert result.as_history() == []
+
+    def test_success_no_compression_with_empty_list(self):
+        result = CompressionResult.success_no_compression([])
+        assert result.success is True
+        assert result.recent_queries == []