diff --git a/docsgpt/api/answer/services/stream_processor.py b/docsgpt/api/answer/services/stream_processor.py
index dd28af81..bfcb25f4 100644
--- a/docsgpt/api/answer/services/stream_processor.py
+++ b/docsgpt/api/answer/services/stream_processor.py
@@ -281,12 +281,26 @@ class StreamProcessor:
         request_data: Dict[str, Any],
         decoded_token: Optional[Dict[str, Any]],
         trace_source: str = "stream",
+        *,
+        external_caller: bool = False,
     ):
+        """Bind a request to its processor.
+
+        Args:
+            request_data: The request body.
+            decoded_token: The caller's token; ``/v1`` passes the agent owner's.
+            trace_source: The entry point the trace is stored under.
+            external_caller: Set by the server for requests authenticated by
+                an agent's API key whose token is the owner's (``/v1``), so
+                the run keeps the key holder's write limits. Never read from
+                the request body.
+        """
         # Legacy attribute retained as None for any external callers that
         # introspect the processor; all DB access uses per-op connections.
         self.prompts_collection = None
         self.data = request_data
         self.decoded_token = decoded_token
+        self.external_caller = bool(external_caller)
         self.initial_user_id = (
             self.decoded_token.get("sub") if self.decoded_token is not None else None
         )
@@ -1043,8 +1057,8 @@ class StreamProcessor:
 
             # Set identity context
             owner = self._agent_data.get("user")
-            self.agent_config["external_api_caller"] = is_external_api_caller(
-                self.data, self.decoded_token, owner,
+            self.agent_config["external_api_caller"] = getattr(self, "external_caller", False) or (
+                is_external_api_caller(self.data, self.decoded_token, owner)
             )
             self.agent_config["api_write_allowlist"] = AgentConfig.parse(
                 self._agent_data.get("config")
@@ -1783,7 +1797,9 @@ class StreamProcessor:
             user=self.initial_user_id,
             decoded_token=self.decoded_token,
             agent_id=agent_id,
-            external_caller=bool(agent_config.get("external_api_caller")),
+            external_caller=bool(
+                agent_config.get("external_api_caller") or getattr(self, "external_caller", False)
+            ),
             public_link_caller=bool(agent_config.get("public_link_caller")),
             api_write_allowlist=agent_config.get("api_write_allowlist"),
         )
diff --git a/docsgpt/api/v1/routes.py b/docsgpt/api/v1/routes.py
index 2b943088..4750f8a9 100644
--- a/docsgpt/api/v1/routes.py
+++ b/docsgpt/api/v1/routes.py
@@ -261,7 +261,9 @@ def chat_completions():
         internal_data["persist"] = True
 
     try:
-        processor = StreamProcessor(internal_data, decoded_token, trace_source="v1")
+        # The token is the owner's, so tell the processor the caller is a key
+        # holder: their writes on the owner's accounts need the allowlist.
+        processor = StreamProcessor(internal_data, decoded_token, trace_source="v1", external_caller=True)
         flush_trace_after_request(processor)
         # Set when this request took the resume claim, so a refusal can release it.
         claimed_conversation_id = None
diff --git a/tests/api/v1/test_v1_external_caller.py b/tests/api/v1/test_v1_external_caller.py
new file mode 100644
index 00000000..c989c327
--- /dev/null
+++ b/tests/api/v1/test_v1_external_caller.py
@@ -0,0 +1,151 @@
+"""``/v1`` key holders are external callers, though the run uses the owner's identity.
+
+The route hands ``StreamProcessor`` the owner's token so state and logs land
+under the owner, which made ``is_external_api_caller`` see the owner and let
+a key holder run (or approve) writes on the owner's connected accounts.
+"""
+
+from __future__ import annotations
+
+import uuid
+from contextlib import ExitStack, contextmanager
+from types import SimpleNamespace
+from unittest.mock import MagicMock, patch
+
+import pytest
+from flask import Flask
+from sqlalchemy import text
+
+from docsgpt.security.encryption import encrypt_json
+
+SP = "docsgpt.api.answer.services.stream_processor"
+
+
+@contextmanager
+def _db(conn):
+    @contextmanager
+    def _yield():
+        yield conn
+
+    with ExitStack() as stack:
+        for module in (SP, "docsgpt.connectors.service", "docsgpt.connectors.resolve"):
+            stack.enter_context(patch(f"{module}.db_readonly", _yield))
+        stack.enter_context(patch(f"{SP}.db_session", _yield))
+        stack.enter_context(patch("docsgpt.connectors.service.db_session", _yield))
+        yield
+
+
+def _run_executor(processor):
+    """The ``ToolExecutor`` the agent run gets from ``create_agent``."""
+    processor._get_prompt_content = MagicMock(return_value="p")
+    processor.prompt_renderer = MagicMock(render_prompt=MagicMock(return_value="p"))
+    processor._enabled_tool_names = MagicMock(return_value=set())
+    processor.model_id = "m1"
+    with patch(f"{SP}.get_provider_from_model_id", return_value="openai"), \
+            patch(f"{SP}.get_api_key_for_provider", return_value="key"), \
+            patch("docsgpt.llm.llm_creator.LLMCreator.create_llm", return_value=MagicMock()), \
+            patch("docsgpt.llm.handlers.handler_creator.LLMHandlerCreator.create_handler"), \
+            patch("docsgpt.agents.agent_creator.AgentCreator.create_agent") as create:
+        processor.create_agent()
+    return create.call_args.kwargs["tool_executor"]
+
+
+class TestV1KeyHolderWrites:
+    def test_connected_write_is_refused_for_a_v1_key_holder(self, pg_conn):
+        from docsgpt.api.answer.services.stream_processor import StreamProcessor
+        from docsgpt.storage.db.repositories.agents import AgentsRepository
+
+        key = f"k-{uuid.uuid4().hex}"
+        AgentsRepository(pg_conn).create("alice", "A", "published", key=key)
+        connection = str(pg_conn.execute(
+            text(
+                "INSERT INTO connector_sessions (user_id, provider, connector_key, auth_kind, status, "
+                "encrypted_credentials) VALUES ('alice', 'telegram', 'telegram', 'api_key', 'connected', :e) "
+                "RETURNING id"
+            ),
+            {"e": encrypt_json({"credentials": {"token": "t"}}, "alice")},
+        ).scalar())
+        tool = {
+            "id": "tool-1", "user_id": "alice", "name": "telegram", "config": {},
+            "actions": [{"name": "telegram_send_message", "active": True, "require_approval": False}],
+            "connection_id": connection, "credential_mode": "owner",
+        }
+
+        # What /v1 builds: the key in the body and the owner's token.
+        processor = StreamProcessor({"api_key": key}, {"sub": "alice"}, external_caller=True)
+        with _db(pg_conn):
+            processor._configure_agent()
+            executor = _run_executor(processor)
+            call = SimpleNamespace(id="c1", name="telegram_send_message", arguments="{}", thought_signature=None)
+            with patch("docsgpt.agents.tool_executor.ToolActionParser") as parser:
+                parser.return_value.parse_args.return_value = ("t1", "telegram_send_message", {})
+                pause = executor.check_pause({"t1": tool}, call, "OpenAILLM")
+        assert executor.external_caller is True
+        assert pause["pause_type"] == "headless_denied"
+        assert pause["error_type"] == "tool_not_allowed"
+
+    def test_resume_stays_external_even_when_state_says_otherwise(self, monkeypatch):
+        """State saved before this fix recorded the key holder as not external."""
+        from docsgpt.agents import agent_creator as ac_mod
+        from docsgpt.api.answer.services import continuation_service as cont_mod
+        from docsgpt.api.answer.services.stream_processor import StreamProcessor
+        from docsgpt.llm import llm_creator as llm_creator_mod
+        from docsgpt.llm.handlers import handler_creator as handler_mod
+
+        cont_service = MagicMock()
+        cont_service.claim_state.return_value = {
+            "messages": [], "pending_tool_calls": [], "tools_dict": {}, "tool_schemas": [],
+            "client_tools": None,
+            "agent_config": {"model_id": "m1", "llm_name": "openai", "api_key": "k", "user_api_key": "uk",
+                             "agent_type": "ClassicAgent", "external_api_caller": False},
+        }
+        monkeypatch.setattr(cont_mod, "ContinuationService", lambda: cont_service)
+        monkeypatch.setattr(llm_creator_mod.LLMCreator, "create_llm", lambda *a, **kw: MagicMock())
+        monkeypatch.setattr(handler_mod.LLMHandlerCreator, "create_handler", lambda *a, **kw: MagicMock())
+        created = {}
+        monkeypatch.setattr(
+            ac_mod.AgentCreator, "create_agent", lambda *a, **kw: created.update(kw) or MagicMock(),
+        )
+        processor = StreamProcessor({}, {"sub": "alice"}, external_caller=True)
+        processor.resume_from_tool_actions(tool_actions=[], conversation_id=str(uuid.uuid4()))
+        assert created["tool_executor"].external_caller is True
+
+
+@pytest.mark.unit
+class TestV1Route:
+    def test_route_marks_the_processor_external(self):
+        from docsgpt.api.v1.routes import v1_bp
+
+        app = Flask(__name__)
+        app.register_blueprint(v1_bp)
+        processor = MagicMock()
+        processor.decoded_token = {"sub": "owner"}
+        processor.agent_config = {"user_api_key": "k"}
+        processor.agent_id = None
+        processor.build_agent.return_value = MagicMock()
+        helper = MagicMock()
+        helper.check_usage.return_value = None
+        helper.complete_stream.return_value = iter(['data: {"type": "end"}'])
+        helper.process_response_stream.return_value = {
+            "error": None, "conversation_id": "c", "answer": "ok", "sources": [], "tool_calls": [], "thought": "",
+        }
+
+        @contextmanager
+        def _conn():
+            yield MagicMock()
+
+        with patch("docsgpt.api.v1.routes._lookup_agent",
+                   return_value={"id": "agent-1", "name": "Agent", "user_id": "owner"}), \
+                patch("docsgpt.api.v1.routes.translate_request",
+                      return_value={"question": "hi", "api_key": "k"}), \
+                patch("docsgpt.api.v1.routes.StreamProcessor", return_value=processor) as cls, \
+                patch("docsgpt.api.v1.routes._V1AnswerHelper", return_value=helper), \
+                patch("docsgpt.api.v1.routes.db_readonly", _conn), \
+                patch("docsgpt.api.v1.routes.translate_response", return_value={"id": "x", "choices": []}):
+            with app.test_client() as client:
+                resp = client.post(
+                    "/v1/chat/completions", headers={"Authorization": "Bearer k"},
+                    json={"messages": [{"role": "user", "content": "hi"}]},
+                )
+        assert resp.status_code == 200
+        assert cls.call_args.kwargs.get("external_caller") is True