---
title: "Remove a participant from an agent thread"
method: DELETE
path: "/api/agent-threads/{threadId}/participants/{userId}"
tags: ["Agent Threads"]
---

# Remove a participant from an agent thread

`DELETE /api/agent-threads/{threadId}/participants/{userId}`

## Request

- The document declares no server URL.
- Auth: one of:
  - API key in header `x-sixb-csrf`
  - HTTP bearer

The thread's owner removes anyone; a participant removes only themself, to leave. Removing someone who does not take part changes nothing.

## Path parameters

- `threadId` string, required
- `userId` string, required

## Response `204`

Response for status 204

- unknown

## Other responses

- `400`: Response for status 400
- `403`: Response for status 403
- `404`: Response for status 404
- `501`: Response for status 501

## Changes

- **2026-10-20** `e7589d61175d`: 1 info
  - endpoint added
- **2026-10-20** `1c47601b37c0`: 1 breaking
  - api path removed without deprecation
- **2026-10-20** `ebeab1520daa`: 1 info
  - endpoint added
- **2026-10-14** `59a844bdcb75`: 1 breaking
  - api path removed without deprecation
- **2026-10-12** `25ac51b05541`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/sixb-ai/apis/sixb-api/changes/api/agent-threads/:threadId/participants/:userId/delete.md)

---

[API](https://skmtc.dev/sixb-ai/apis/sixb-api.md) - [All operations](https://skmtc.dev/sixb-ai/apis/sixb-api/llms.txt) - [OpenAPI document](https://skmtc.dev/sixb-ai/apis/sixb-api/revisions/a227d682eaa2?raw)