diff --git a/engines/temporal/internal/gateway/invoke.go b/engines/temporal/internal/gateway/invoke.go
index c5c99f0..9e8b950 100644
--- a/engines/temporal/internal/gateway/invoke.go
+++ b/engines/temporal/internal/gateway/invoke.go
@@ -294,8 +294,15 @@ func (s *Server) handleInvokeStatus(c *gin.Context) {
 			ToolCalls: result.PendingToolCalls,
 		})
 
-	case ctx.Err() != nil && c.Request.Context().Err() == nil:
-		// Our own deadline, not the client's: the turn is simply still running.
+	case ctx.Err() != nil && c.Request.Context().Err() == nil, isTransportTimeoutOrCancel(err):
+		// Either our own invokePollTimeout lapsed, or the SDK's long-poll gRPC
+		// call was itself cancelled/timed out (WorkflowUpdateServiceTimeoutOr
+		// CanceledError -- e.g. "stream terminated by RST_STREAM with error
+		// code: CANCEL"). The SDK documents that error as being about the
+		// client call, NOT the update: the workflow is still running either
+		// way. Reporting it as "failed" here made agent-orchestrator surface
+		// a bridged coding agent's routine multi-minute turn as an outright
+		// failure while the AgentRun kept working in the background.
 		// Best-effort narration alongside it -- a query failure or an inactive
 		// turn (nothing narrated yet) just means an empty Progress, never an
 		// error response, since the pending status itself is still accurate.
@@ -326,6 +333,19 @@ func isUnknownUpdate(err error) bool {
 	return errors.As(err, &notFound)
 }
 
+// isTransportTimeoutOrCancel reports whether err is the SDK's
+// WorkflowUpdateServiceTimeoutOrCanceledError (e.g. wrapping "stream
+// terminated by RST_STREAM with error code: CANCEL") -- a gRPC long-poll call
+// that got cancelled or timed out on its own terms, independent of our
+// invokePollTimeout ever firing. The SDK's own doc comment on the type is
+// explicit that this is "not related to any general concept of timing out or
+// cancelling a running update": the workflow update itself is unaffected.
+// See awaitTurnResult in server.go for the streaming endpoint's analogous fix.
+func isTransportTimeoutOrCancel(err error) bool {
+	var pollErr *client.WorkflowUpdateServiceTimeoutOrCanceledError
+	return errors.As(err, &pollErr)
+}
+
 // Invocation ids join the two halves Temporal needs to reconstruct an update
 // handle. A '.' is unambiguous as the separator: sanitizeID maps everything
 // outside [A-Za-z0-9_-] to '-', so the workflow id half never contains one,
diff --git a/engines/temporal/internal/gateway/invoke_status_test.go b/engines/temporal/internal/gateway/invoke_status_test.go
new file mode 100644
index 0000000..53d94e3
--- /dev/null
+++ b/engines/temporal/internal/gateway/invoke_status_test.go
@@ -0,0 +1,107 @@
+package gateway
+
+// Internal test: handleInvokeStatus is the /invoke poll endpoint
+// agent-orchestrator drives for every bridged-agent turn. A fake
+// client.Client (embedding the interface so only the two methods this
+// handler calls need overriding) is enough to reach every branch without
+// standing up Temporal.
+
+import (
+	"context"
+	"errors"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/gin-gonic/gin"
+	"github.com/stretchr/testify/require"
+	"go.temporal.io/api/serviceerror"
+	"go.temporal.io/sdk/client"
+	"go.temporal.io/sdk/converter"
+)
+
+// fakeTemporalClient overrides only what handleInvokeStatus calls; every
+// other client.Client method panics if reached, which would fail the test
+// loudly rather than silently doing the wrong thing.
+type fakeTemporalClient struct {
+	client.Client
+	handle client.WorkflowUpdateHandle
+}
+
+func (f *fakeTemporalClient) GetWorkflowUpdateHandle(client.GetWorkflowUpdateHandleOptions) client.WorkflowUpdateHandle {
+	return f.handle
+}
+
+func (f *fakeTemporalClient) QueryWorkflow(context.Context, string, string, string, ...interface{}) (converter.EncodedValue, error) {
+	return nil, errors.New("no progress recorded in this test")
+}
+
+func invokeStatusRequest(t *testing.T, s *Server, invocationID string) *httptest.ResponseRecorder {
+	t.Helper()
+	gin.SetMode(gin.TestMode)
+	rec := httptest.NewRecorder()
+	c, _ := gin.CreateTestContext(rec)
+	c.Params = gin.Params{{Key: "id", Value: invocationID}}
+	c.Request = httptest.NewRequest("GET", "/invoke/"+invocationID, nil)
+	s.handleInvokeStatus(c)
+	return rec
+}
+
+// The regression this exists for: the SDK's long-poll gRPC call getting
+// cancelled or timing out on its own terms (surfacing as e.g. "stream
+// terminated by RST_STREAM with error code: CANCEL") is NOT the update
+// failing -- the SDK's own doc comment says so explicitly -- but reporting it
+// as invokeStatusFailed made agent-orchestrator show a bridged coding agent's
+// routine multi-minute turn as an outright failure while the AgentRun kept
+// working in the background.
+func TestHandleInvokeStatusTreatsTransportCancelAsPending(t *testing.T) {
+	handle := &fakeUpdateHandle{errs: []error{
+		client.NewWorkflowUpdateServiceTimeoutOrCanceledError(errors.New("stream terminated by RST_STREAM with error code: CANCEL")),
+	}}
+	s := NewServer(&fakeTemporalClient{handle: handle}, "task-queue", nil)
+
+	rec := invokeStatusRequest(t, s, encodeInvocationID("conversation-abc", "6ba7b810-9dad-11d1-80b4-00c04fd430c8"))
+
+	require.Equal(t, 200, rec.Code)
+	require.JSONEq(t, `{"id":"conversation-abc.6ba7b810-9dad-11d1-80b4-00c04fd430c8","status":"pending"}`, rec.Body.String())
+}
+
+// A genuinely failed update (the workflow rejected it, or the turn errored)
+// must still surface as failed -- only the transport-cancellation shape is
+// reclassified.
+func TestHandleInvokeStatusReportsARealFailure(t *testing.T) {
+	handle := &fakeUpdateHandle{errs: []error{errors.New("turn failed: launch_error")}}
+	s := NewServer(&fakeTemporalClient{handle: handle}, "task-queue", nil)
+
+	rec := invokeStatusRequest(t, s, encodeInvocationID("conversation-abc", "6ba7b810-9dad-11d1-80b4-00c04fd430c8"))
+
+	require.Equal(t, 200, rec.Code)
+	require.JSONEq(t, `{"id":"conversation-abc.6ba7b810-9dad-11d1-80b4-00c04fd430c8","status":"failed","error":"turn failed: launch_error"}`, rec.Body.String())
+}
+
+// An id naming an update Temporal has never heard of (aged-out workflow, or a
+// caller-forged id) is a 404, distinct from a turn that ran and failed.
+func TestHandleInvokeStatusUnknownUpdateIs404(t *testing.T) {
+	handle := &fakeUpdateHandle{errs: []error{serviceerror.NewNotFound("not found")}}
+	s := NewServer(&fakeTemporalClient{handle: handle}, "task-queue", nil)
+
+	rec := invokeStatusRequest(t, s, encodeInvocationID("conversation-abc", "6ba7b810-9dad-11d1-80b4-00c04fd430c8"))
+
+	require.Equal(t, 404, rec.Code)
+}
+
+// A turn that succeeds on the very next poll (no transport hiccup at all)
+// still reports normally -- the transport-cancel handling above must not
+// swallow or delay an ordinary success.
+func TestHandleInvokeStatusSucceededReportsTheReply(t *testing.T) {
+	handle := &fakeUpdateHandle{reply: "Opened PR #42."}
+	s := NewServer(&fakeTemporalClient{handle: handle}, "task-queue", nil)
+
+	rec := invokeStatusRequest(t, s, encodeInvocationID("conversation-abc", "6ba7b810-9dad-11d1-80b4-00c04fd430c8"))
+
+	require.Equal(t, 200, rec.Code)
+	require.JSONEq(t, `{
+		"id":"conversation-abc.6ba7b810-9dad-11d1-80b4-00c04fd430c8",
+		"status":"succeeded",
+		"result":"Opened PR #42."
+	}`, rec.Body.String())
+}