---
title: "Add an agent to a thread"
method: POST
path: "/threads/{id}/agents"
---

# Add an agent to a thread

`POST /threads/{id}/agents`

## Request

- Base URL: `https://api.agentsky.dev/v1`
- URL: `https://api.agentsky.dev/v1/threads/{id}/agents`
- Auth: HTTP bearer

Add one more agent beside the thread's others, in a session of its own, with no message sent to it. The same `requestId` replays the first outcome.

## Path parameters

- `id` string, required

## Request body

- object
  - `requestId` string, required
  - `agentType` string, required
  - `llm` string
  - `reasoningEffort` string, nullable
  - `timezone` string

## Response `201`

OK

- object
  - `columns` ThreadAgentRef[]
    - `columnId` string
    - `sessionId` string

## Other responses

- `400`: Error — { error: { code, message } }
- `401`: Error — { error: { code, message } }
- `403`: Error — { error: { code, message } }
- `404`: Error — { error: { code, message } }
- `422`: Error — { error: { code, message } }
- `default`: Error — { error: { code, message, request_id } }

## Changes

- **2026-11-02** `e5e8f0229a99`: 1 info
  - endpoint added

[Operation history](https://skmtc.dev/agentsky/apis/agentsky-developer-api/changes/threads/:id/agents/post.md)

---

[API](https://skmtc.dev/agentsky/apis/agentsky-developer-api.md) - [All operations](https://skmtc.dev/agentsky/apis/agentsky-developer-api/llms.txt) - [OpenAPI document](https://skmtc.dev/agentsky/apis/agentsky-developer-api/revisions/0d435187cd55?raw)