HKUDS/Vibe-Trading · error · HTTPException

Session {session_id} not found

Error message

Session {session_id} not found

What it means

After the session service is located, _get_existing_session_or_404 calls svc.get_session(session_id); a None result (unknown, deleted, or expired/persisted-out session id) becomes 404 with the offending id in the detail. Path params are also validated upstream, so this specifically means 'well-formed but nonexistent'.

Source

Thrown at agent/src/api/sessions_routes.py:358

        h = _sys.modules.get("api_server") or _sys.modules.get("agent.api_server")
        return h._get_session_service()

    def _host_validate_path_param(value: str, kind: str) -> None:
        h = _sys.modules.get("api_server") or _sys.modules.get("agent.api_server")
        return h._validate_path_param(value, kind)

    def _host_shell_tools_enabled_for_request(request: Request) -> bool:
        h = _sys.modules.get("api_server") or _sys.modules.get("agent.api_server")
        return h._shell_tools_enabled_for_request(request)

    def _get_existing_session_or_404(session_id: str):
        """Return (service, session) or raise 404."""
        svc = _host_get_session_service()
        if not svc:
            raise HTTPException(status_code=501, detail="Session runtime not enabled")
        session = svc.get_session(session_id)
        if not session:
            raise HTTPException(status_code=404, detail=f"Session {session_id} not found")
        return svc, session

    # -----------------------------------------------------------------------
    # Session CRUD routes
    # -----------------------------------------------------------------------

    @app.post("/sessions", response_model=SessionResponse, status_code=status.HTTP_201_CREATED)
    async def create_session(
        request: CreateSessionRequest,
        principal=Depends(require_auth),
    ):
        """Create a chat session.

        The authenticated principal is recorded as the session owner. Under the
        shared-key and loopback auth modes that principal is not attributable to
        a named human -- it carries ``attributable=False`` and must not be read
        as an identity. Recording it anyway is still worth doing: it captures
        HOW the session was authorised, which is the part that becomes an

View on GitHub (pinned to 80ffdda44c)

Solutions

  1. List sessions (GET /sessions) to confirm the id still exists and matches
  2. Re-create the session (POST /sessions) and retry the goal operation with the new id
  3. If sessions should survive restarts, enable session persistence in the service configuration
  4. Verify the client targets the correct environment/host

Example fix

# before
goal = api.create_session_goal(session_id="sess-old", ...)  # 404

# after
sessions = api.list_sessions()
sid = next(s for s in sessions if s.title == "research") .session_id
goal = api.create_session_goal(session_id=sid, ...)
Defensive patterns

Strategy: validation

Validate before calling

def session_exists(client, sid: str) -> bool:
    return any(s["session_id"] == sid for s in client.get("/sessions", params={"limit": 200}).json())

Type guard

import re
SESSION_ID_RE = re.compile(r"^[A-Za-z0-9_-]+$")
def is_valid_session_id(sid: str) -> bool:
    return bool(sid) and SESSION_ID_RE.match(sid) is not None

Try / catch

try:
    return api.get_session_goal(sid)
except NotFoundError as e:
    if "Session" in str(e):
        sid = recreate_session(api)  # or surface 'session expired' to the user
        return api.get_session_goal(sid)
    raise

Prevention

When it happens

Trigger: Calling create_session_goal, get_session_goal, update_session_goal, add_session_goal_evidence, or update_session_goal_status with a session_id that no session store contains — deleted session, wrong id, or one from another server instance.

Common situations: Client holds a stale session id after the store was reset/restarted without persistence; copy-paste typo in the id; pointing a client at a different environment (dev id used against prod); session TTL cleanup removed it.

Understand the failure class

Background: 'Could not be found', 'does not exist', 'not found in database': the resource-not-found family when an ID, slug, key, or URI lookup comes back empty — this error's family across 20 libraries.

Related errors

AI-assisted analysis of HKUDS/Vibe-Trading@80ffdda44c (2026-08-28). Data as JSON: /api/errors/25cb2f2a989a2d6e. Report an issue: GitHub.