diff --git a/internal/gateway/bridge_context_test.go b/internal/gateway/bridge_context_test.go
new file mode 100644
index 00000000..04e0ab7a
--- /dev/null
+++ b/internal/gateway/bridge_context_test.go
@@ -0,0 +1,90 @@
+package gateway
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/google/uuid"
+
+	"github.com/nextlevelbuilder/goclaw/internal/providers"
+	"github.com/nextlevelbuilder/goclaw/internal/store"
+	"github.com/nextlevelbuilder/goclaw/internal/tools"
+)
+
+// stubAgentKeyStore satisfies store.AgentStore via an embedded (nil) interface and
+// implements only GetByIDUnscoped — the single method bridgeContextMiddleware calls.
+type stubAgentKeyStore struct {
+	store.AgentStore
+	ag *store.AgentData
+}
+
+func (s *stubAgentKeyStore) GetByIDUnscoped(context.Context, uuid.UUID) (*store.AgentData, error) {
+	return s.ag, nil
+}
+
+// TestBridgeContextMiddleware_InjectsAgentKey guards the MCP bridge identity path:
+// a signed X-Agent-ID must put the agent key into the tool context
+// (tools.ToolAgentKeyFromCtx). Session tools (sessions_list/history/send) resolve the
+// caller via that key and otherwise fail with "agent context required".
+func TestBridgeContextMiddleware_InjectsAgentKey(t *testing.T) {
+	const (
+		gatewayToken = "test-gateway-token"
+		wantKey      = "vault-keeper"
+	)
+	agentID := uuid.New()
+	agentStore := &stubAgentKeyStore{ag: &store.AgentData{AgentKey: wantKey}}
+
+	var handlerCalled bool
+	var gotKey string
+	next := http.HandlerFunc(func(_ http.ResponseWriter, r *http.Request) {
+		handlerCalled = true
+		gotKey = tools.ToolAgentKeyFromCtx(r.Context())
+	})
+
+	mw := bridgeContextMiddleware(gatewayToken, agentStore, next)
+
+	// Sign X-Agent-ID exactly as the claude-cli provider does: empty user/channel/
+	// chat/peer/workspace/tenant plus the two trailing extras (localKey, sessionKey).
+	sig := providers.SignBridgeContext(gatewayToken, agentID.String(), "", "", "", "", "", "", "", "")
+	req := httptest.NewRequest(http.MethodPost, "/mcp/bridge", nil)
+	req.Header.Set("X-Agent-ID", agentID.String())
+	req.Header.Set("X-Bridge-Sig", sig)
+
+	mw.ServeHTTP(httptest.NewRecorder(), req)
+
+	if !handlerCalled {
+		t.Fatal("next handler was not called: middleware rejected the signed request")
+	}
+	if gotKey != wantKey {
+		t.Errorf("ToolAgentKeyFromCtx = %q, want %q", gotKey, wantKey)
+	}
+}
+
+// TestBridgeContextMiddleware_NoStore_NoAgentKey is the negative control: with no
+// agent store wired (or an unsigned request), the agent key must stay empty so the
+// regression that motivated this fix cannot silently reappear masked by a default.
+func TestBridgeContextMiddleware_NoStore_NoAgentKey(t *testing.T) {
+	const gatewayToken = "test-gateway-token"
+	agentID := uuid.New()
+
+	var gotKey string
+	next := http.HandlerFunc(func(_ http.ResponseWriter, r *http.Request) {
+		gotKey = tools.ToolAgentKeyFromCtx(r.Context())
+	})
+
+	// agentStore == nil: middleware injects the UUID but has no row to recover the key from.
+	mw := bridgeContextMiddleware(gatewayToken, nil, next)
+
+	sig := providers.SignBridgeContext(gatewayToken, agentID.String(), "", "", "", "", "", "", "", "")
+	req := httptest.NewRequest(http.MethodPost, "/mcp/bridge", nil)
+	req.Header.Set("X-Agent-ID", agentID.String())
+	req.Header.Set("X-Bridge-Sig", sig)
+
+	mw.ServeHTTP(httptest.NewRecorder(), req)
+
+	if gotKey != "" {
+		t.Errorf("ToolAgentKeyFromCtx = %q, want empty when no agent store is wired", gotKey)
+	}
+}
diff --git a/internal/gateway/server.go b/internal/gateway/server.go
index 6cb1b0cf..717f7a45 100644
--- a/internal/gateway/server.go
+++ b/internal/gateway/server.go
@@ -279,6 +279,11 @@ func bridgeContextMiddleware(gatewayToken string, agentStore store.AgentStore, n
 					if agentStore != nil {
 						ag, err := agentStore.GetByIDUnscoped(ctx, id)
 						if err == nil && ag != nil {
+							// Propagate the agent key so bridged session tools (sessions_list/
+							// history/send) can resolve identity via ToolAgentKeyFromCtx. The MCP
+							// bridge otherwise injects only the agent UUID, leaving the key empty
+							// -> session tools fail with "agent context required".
+							ctx = tools.WithToolAgentKey(ctx, ag.AgentKey)
 							groups := ag.ParseShellDenyGroups()
 							if groups != nil {
 								ctx = store.WithShellDenyGroups(ctx, groups)