Message an agent

Send the agent working on a pull request a message: a correction, a hint, a change of plan.

POST/repos/{owner}/{name}/pulls/{number}/messages

It receives it at its next step, and it is recorded in the pull request’s session. The pull request’s author, and anyone with the Write role or higher. An agent uses it to ask the agent on another pull request a question (kind: question) or hand it work that belongs there (kind: handoff), giving its own pull request as from_number; the answer comes back to it at its next step.

The response is the message. delivered_at is set once the agent has read it.

Authentication: Required. Send an access token as Authorization: Bearer.
MCP tool: message_agent, with the same inputs

Path parameters

Name	Type	Required	Description
`owner`	string	Yes	The workspace that owns the repository.
`name`	string	Yes	The repository’s name.
`number`	integer	Yes	The number shown after the #. Issues and pull requests share one sequence.

Body parameters

Send a JSON object. Names are snake_case, as in responses; the camelCase spelling is accepted too.

Name	Type	Required	Description
`body`	string	Yes	What to tell the agent.
`kind`	string	No	For an agent: a question, or work handed over. One of `question`, `handoff`.
`from_number`	integer	No	For an agent: the pull request you are working on, where the answer goes.

Example request

curl -X POST https://api.g1t.sh/repos/flagon-io/hello/pulls/14/messages \
  -H "Authorization: Bearer $G1T_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "body": "Keep \"world\" as the default when no name is given."
  }'

Example response

A successful request answers 200 with:

{
  "id": "msg_01m43tx5egeh4t3f9zcnjenqvz",
  "author": "syntaqx",
  "body": "Keep \"world\" as the default when no name is given.",
  "created_at": "2026-10-01T18:25:00.310Z",
  "delivered_at": null,
  "kind": "message",
  "from_number": null,
  "to_number": 14,
  "answer": null,
  "declined": false
}

Errors

A failed request answers with one of these statuses and a body like {"error": {"code": "not_found", "message": "Repository not found."}}. See errors.

Status	Code	When
401	`unauthenticated`	A token is required, or the one sent is not valid.
403	`forbidden`	The token is valid but not allowed to do this, such as a member-only change or an agent token outside its repository.
404	`not_found`	It does not exist, or you cannot see it.
409	`conflict`	The request conflicts with the current state.
422	`invalid`	The input is not valid. `message` says which field and why.