Chat Completions
Authorizations
Enter your MeshAPI key (rsk_...) or, for the admin-keys endpoints, a dashboard session token — sent as Authorization: Bearer <token>.
Headers
Dated version of the API contract to pin this request to. Omit it and the request is served under 2026-08 — the oldest supported version, so an existing integration is never moved by a release. A malformed or unsupported value is rejected with 400 invalid_api_version rather than falling back silently. The version actually served is echoed as X-Mesh-Version on every response, including errors.
2026-08, 2026-09 Body
0 <= x <= 2x >= 10 <= x <= 1-2 <= x <= 2-2 <= x <= 2high, medium, low, none Structured reasoning object (supersedes reasoning_effort).
effort and max_tokens are mutually exclusive: effort is the
OpenAI/Grok dial, max_tokens the Anthropic/Gemini/Qwen thinking budget.
exclude reasons internally but omits the content from the response.
enabled: true alone means "reason at defaults"; false disables.
context/mode are gpt-5.x-only passthroughs.
- Tool
- ServerTool
A stable, anonymised identifier for the end user making this request, recorded on the usage row and available as a filter and a group-by dimension in the usage API. Supersedes the deprecated user field. Use an opaque id, not an email address or a name.
256256text, image text, audio, image x > 0auto, default, flex Your own labels for this request, echoed back on the usage row and available as a filter and a group-by dimension in the usage API. String keys to string values. Never put personal or sensitive data here — tags are stored with the usage record and are not redacted.
Response
Completion (JSON), or an SSE stream when stream=true
On chat completions every key below is present, 0 when unused, whoever served it. Any other key the serving provider reports is passed through as sent.