microsoft/autogen · error · Error

Failed to fetch sessions

Error message

Failed to fetch sessions

What it means

Thrown by SessionAPI.listSessions when GET /sessions/?user_id=... returns a body with a falsy status field. Note the check is on data.status (the application-level envelope), not response.ok — so this fires even on HTTP 200 whenever the backend marks the operation failed. It also throws on non-JSON error bodies only indirectly (json() would throw first).

Source

Thrown at python/packages/autogen-studio/frontend/src/components/views/playground/api.ts:14

import { Session, SessionRuns } from "../../types/datamodel";
import { BaseAPI } from "../../utils/baseapi";

export class SessionAPI extends BaseAPI {
  async listSessions(userId: string): Promise<Session[]> {
    const response = await fetch(
      `${this.getBaseUrl()}/sessions/?user_id=${userId}`,
      {
        headers: this.getHeaders(),
      }
    );
    const data = await response.json();
    if (!data.status)
      throw new Error(data.message || "Failed to fetch sessions");
    return data.data;
  }

  async getSession(sessionId: number, userId: string): Promise<Session> {
    const response = await fetch(
      `${this.getBaseUrl()}/sessions/${sessionId}?user_id=${userId}`,
      {
        headers: this.getHeaders(),
      }
    );
    const data = await response.json();
    if (!data.status)
      throw new Error(data.message || "Failed to fetch session");
    return data.data;
  }

  async createSession(
    sessionData: Partial<Session>,

View on GitHub (pinned to 027ecf0a37)

Solutions

1. Log the full response body — data.message identifies which envelope failure it is
2. Ensure userId is a real non-empty value before calling (guard against undefined during initial load)
3. Verify the auth token matches the user_id being queried
4. Hit GET /sessions/?user_id=... directly with curl to see the raw envelope
5. If data is undefined because the body was an HTML error page, harden the json parse (see exampleFix)

Example fix

// before
const response = await fetch(`${this.getBaseUrl()}/sessions/?user_id=${userId}`, { headers: this.getHeaders() });
const data = await response.json();
if (!data.status) throw new Error(data.message || "Failed to fetch sessions");
// after
const response = await fetch(`${this.getBaseUrl()}/sessions/?user_id=${encodeURIComponent(userId)}`, { headers: this.getHeaders() });
if (!response.ok) throw new Error(`Failed to fetch sessions (HTTP ${response.status})`);
const data = await response.json();
if (!data.status) throw new Error(data.message || "Failed to fetch sessions");

function isValidUserId(u: string | undefined | null): u is string {
  return typeof u === "string" && u.length > 0;
}
// gate the call
if (!isValidUserId(userId)) throw new Error("userId not loaded yet");

function isSessionListEnvelope(x: unknown): x is { status: true; data: Session[] } {
  return !!x && typeof x === "object" && (x as any).status === true && Array.isArray((x as any).data);
}

try {
  setSessions(await sessionAPI.listSessions(userId));
} catch (e) {
  setSessions([]);
  notify(e instanceof Error ? e.message : "Failed to fetch sessions");
}

When it happens

Trigger: GET {base}/sessions/?user_id=X returning {status:false,...}: invalid/empty user_id, user not found in the backend DB, auth token rejected (backend answers 200/401 with status:false envelope), or backend DB unavailable.

Common situations: user_id not yet loaded (empty string) when the call fires on mount, user deleted/recreated while token stale, fresh database with no migrations, auth mismatch between token subject and user_id param.

Related errors

• Failed to fetch session
• Failed to list MCP tools
• Failed to call MCP tool
• MCP health check failed
• HTTP ${response.status}: ${errorText || "Failed to create We

AI-assisted analysis of microsoft/autogen@027ecf0a37 (2026-08-15). Data as JSON: /api/errors/16a5a9f94d9b960c. Report an issue: GitHub.