---
title: "Set Participant Mode"
method: PATCH
path: "/api/chats/{chat_id}/participants/{identity_id}/mode"
tags: ["chats"]
---

# Set Participant Mode

`PATCH /api/chats/{chat_id}/participants/{identity_id}/mode`

## Request

- Base URL: `https://app.thinqos.com` (the document declares no server; this is the origin it was published from)
- URL: `https://app.thinqos.com/api/chats/{chat_id}/participants/{identity_id}/mode`
- Auth: none declared

Update mode_override for a chat participant (TOS-246 Phase D).

Authorization:
  - Caller may update the mode of the identity they are currently acting as
    — i.e., the identity resolved by ``get_identity`` (self, or the
    ``X-Impersonate-Identity-Id`` target). Plain ownership via
    ``identity_controllers`` does NOT grant this right; the owner must
    be impersonating the agent. (TOS-305)

Raises:
  - 404 if the chat does not exist or the target is not an active participant.
  - 403 if the caller is not acting as the target identity.
  - 422 if mode_override is an invalid enum value (FastAPI/Pydantic auto-rejects).

## Path parameters

- `chat_id` string, uuid, required
- `identity_id` string, uuid, required

## Headers

- `x-impersonate-identity-id` string, nullable

## Request body

- ParticipantModeUpdate
  - `mode_override` 'human' | 'agent_augmented' | 'agent', nullable, required
  - `mode_override_expires_at` string, date-time, nullable
  - `agent_auto_reply_limit` integer, nullable
  - `agent_auto_reply_window_seconds` integer, nullable

## Response `200`

Successful Response

- ParticipantModeResponse
  - `identity_id` string, uuid, required
  - `mode_override` 'human' | 'agent_augmented' | 'agent', nullable, required
  - `mode_override_expires_at` string, date-time, nullable
  - `agent_auto_reply_limit` integer, nullable
  - `agent_auto_reply_window_seconds` integer, nullable

## Other responses

- `422`: Validation Error

---

[API](https://skmtc.dev/thinqos/apis/thinqos-api.md) · [All operations](https://skmtc.dev/thinqos/apis/thinqos-api/llms.txt) · [OpenAPI document](https://skmtc.dev/thinqos/apis/thinqos-api/revisions/5387b4ded614?raw)