---
title: "Send an event to a running session"
method: POST
path: "/code/sessions/{sessionId}/events"
---

# Send an event to a running session

`POST /code/sessions/{sessionId}/events`

## Request

- Base URL: `https://api.caveman.so/api/v1`
- URL: `https://api.caveman.so/api/v1/code/sessions/{sessionId}/events`
- Auth: one of:
  - OAuth 2
    - Authorization code: `/api/v1/oauth/authorize`
    - Token URL: `/api/v1/oauth/token` scopes: `code:write`
  - HTTP bearer
  - API key in cookie `cave_access`
  - API key in cookie `__Secure-cave_identity.session_token`

POST /api/v1/code/sessions/{sessionId}/events on the Caveman Cloud control plane. Requires the code:write scope. Not exposed to autonomous agents: The Agents API is driven by a service account's code:run key, or by a person in the Code app and console. An agent connection works inside a Code session and never starts, lists or drives Code sessions or agents from a control-plane connection.

## Request body

- object
  - `request_id` string, required
  - `type` 'user.message' | 'user.interrupt' | 'user.approval' | 'user.answer' | 'user.tool_result', required
  - `text` string
  - `ask_id` string
  - `decision` 'allow' | 'deny'
  - `message` string
  - `content` string
  - `is_error` boolean

## Response `200`

The mail the event became

- CodeMail: The mailbox message an event to a session became, delivered to the session's computer.
  - `id` string, uuid, required
  - `verb` 'task' | 'interrupt' | 'answer', required
  - `authority` 'human' | 'api' | 'automation', required
  - `channel` string, required
  - `to_workspace_id` string, uuid, nullable
  - `body` string
  - `wakes` boolean, required
  - `created_at` string, date-time, required
  - `payload` object

## Other responses

- `401`: A person's sign-in or a code:run key is required.
- `403`: The role, the key's scope, or an inactive service account (cave_code_service_account_inactive) refuses.
- `404`: Not a session this caller may drive.
- `409`: The session ended, or its budget is spent.
- `2XX`: Successful response. Exact status depends on synchronous or durable delivery outcome.
- `4XX`: Structured failure. `error.code` is stable; `error.request_id` is echoed in the x-cave-request-id header.
- `5XX`: Structured failure. `error.code` is stable; `error.request_id` is echoed in the x-cave-request-id header.

---

[API](https://skmtc.dev/caveman/apis/caveman-cloud-api.md) - [All operations](https://skmtc.dev/caveman/apis/caveman-cloud-api/llms.txt) - [OpenAPI document](https://skmtc.dev/caveman/apis/caveman-cloud-api/revisions/508312d01cfc?raw)