---
title: "OAuth 2.0 token introspection (RFC 7662)"
method: POST
path: "/oauth/introspect"
tags: ["OAuth"]
---

# OAuth 2.0 token introspection (RFC 7662)

`POST /oauth/introspect`

## Request

- Base URL: `https://api.mnemom.ai/v1`
- URL: `https://api.mnemom.ai/v1/oauth/introspect`
- Auth: one of:
  - HTTP bearer
  - API key in header `X-Mnemom-Api-Key`
  - API key in cookie `mnemom_session`

Returns the activeness + metadata of an access token per RFC 7662. The caller MUST authenticate: because Mnemom's OAuth clients are public (no client secret), there is no client-credentials path, so the caller authenticates as a USER (bearer / api-key / cookie). active:true with full metadata is returned ONLY when the token is live AND the authenticated caller owns/admins the token's org; otherwise the response is {active:false} with no other fields — the endpoint is never a token existence/validity oracle for tokens the caller does not control. Only opaque access tokens (mcp_at_) are introspectable; refresh tokens and unknown values report active:false.

## Request body

- object
  - `token` string, required: The access token to introspect.
  - `token_type_hint` 'access_token'

## Response `200`

RFC 7662 introspection response.

- object
  - `active` boolean, required
  - `scope` string
  - `client_id` string
  - `token_type` 'Bearer'
  - `exp` integer: Expiry, seconds since epoch.
  - `sub` string: The consenting user id.
  - `org_id` string

## Other responses

- `400`: Bad request
- `401`: Authentication required
- `403`: Cross-origin write refused (`cross_origin_rejected`). A state-changing request that carries the browser session cookie must come from a first-party origin (`Origin`, or failing that `Referer`) and must not send a form-style body (text/plain, urlencoded, multipart) the operation does not declare. Bearer and API-key callers are never subject to this check.
- `429`: Rate-limit exceeded. The global per-IP limiter (100 requests/minute, applied to every `/v1/*` route) rejected this request. Back off until the window resets — `Retry-After` carries the cooldown in seconds and `X-RateLimit-Reset` the absolute reset time.
- `500`: Server error — request was well-formed but the server failed to fulfill it. Typically a downstream dependency (DB / RPC / external API) returned an unexpected error.

---

[API](https://skmtc.dev/mnemom/apis/mnemom-api.md) · [All operations](https://skmtc.dev/mnemom/apis/mnemom-api/llms.txt) · [OpenAPI document](https://skmtc.dev/mnemom/apis/mnemom-api/revisions/274b7a6ea182?raw)