Add labels to an issue

Add labels to an issue or a pull request, keeping the ones it has.

POST/repos/{owner}/{name}/issues/{number}/labels

A name the repository does not have yet is created when you have the Write role or higher; without it, you may use the repository’s labels on what you opened. Each label added is an issue.labeled or pull.labeled event. Returns its labels now, at most 20.

Returns its labels now, by name.

Authentication: Required. Send an access token as Authorization: Bearer.
MCP tool: issue with action add_labels, and the same inputs
Scope: An access token needs issues:write.

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
`labels`	array of strings	Yes	Label names, e.g. [“bug”, “help wanted”]. Names the repository does not have yet are created for someone with the Write role.

Example request

curl -X POST https://api.g1t.sh/repos/flagon-io/hello/issues/12/labels \
  -H "Authorization: Bearer $G1T_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "labels": [
      "help wanted"
    ]
  }'

Example response

A successful request answers 200 with:

[
  "bug",
  "help wanted"
]

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.