odysseus-dev/odysseus · error · Error

Server returned no session id

Error message

Server returned no session id

What it means

Thrown in the same _chatAboutResearch flow (research/panel.js:1239) when the spinoff endpoint returns 200 OK but the JSON payload has no session_id. Per the inline comment this is a server contract violation: success status without the field needed to route the user to the new chat. The button is un-stuck and the failure alerted rather than silently ignored.

Source

Thrown at static/js/research/panel.js:1239:1239

    const payload = await res.json();
    if (_sessionModule && _sessionModule.selectSession && payload.session_id) {
      if (_sessionModule.loadSessions) await _sessionModule.loadSessions().catch(() => {});
      await _sessionModule.selectSession(payload.session_id);
      closePanel();
    } else if (payload.session_id) {
      window.location.hash = '#' + payload.session_id;
      window.location.reload();
    } else {
      // 200 OK but no session_id — server contract violation. Don't leave
      // the button stuck on 'Creating…'; surface the failure instead.
      throw new Error('Server returned no session id');
    }

View on GitHub (pinned to f9235ebbf1)

Solutions

1. Inspect the actual 200 response body in the network tab to see which field holds the id.
2. Update the client to read the current field name, or the server to emit session_id.
3. Ensure client and server builds are from the same release.
4. Fix test/mocks to include session_id.

const isSpinoffPayload = (p) => !!p && (typeof p.session_id === 'string' || typeof p.session_id === 'number');

try { const payload = await res.json(); if (!isSpinoffPayload(payload)) throw new Error('Server returned no session id'); } catch (e) { btn.disabled = false; btn.innerHTML = origLabel; alert('Could not start follow-up chat: ' + e.message); }

When it happens

Trigger: Backend version that returns {chat_id} instead of {session_id}; a proxy or middleware stripping/rewriting the response body; server short-circuits with an empty object on partial creation (session created but id serialization failed).

Common situations: Client/server version skew after renaming the response field; mock servers returning incomplete payloads; serialization bugs where the ORM id is not included.

Related errors

• ${cfg.label} sign-in did not return a poll id
• detail || `HTTP ${res.status}`
• Session request returned an invalid response
• HTTP ' + r.status
• detail || ('HTTP ' + res.status)

AI-assisted analysis of odysseus-dev/odysseus@f9235ebbf1 (2026-08-14). Data as JSON: /api/errors/130385bceeaedd27. Report an issue: GitHub.