Start a sprint

POSThttps://<your-url>/api/v2/sprints/{sprint}/actions/start

MCP id sprints.actions.start

Activates a sprint: sets is_active to true and stamps started_at with the current time.

Token scope: api:write:project_management
Without it: 403 insufficient-token-scope.
Permission: project_management::manage_sprints
Without it: 403 insufficient-permission.
Rate cost: 1 unit, write bucket. A write costs the same whatever view you ask for.
Also: Accepts Idempotency-Key. Accepts If-Match. Never cached: private, no-store. Unknown query parameters are refused, never ignored.

Both are checked, scope first. A token never does more than its user. How access is checked

Request

Example: Start the next sprint

curl -X POST \
  'https://<your-url>/api/v2/sprints/1/actions/start' \
  -H 'Authorization: Bearer <token>' \
  -H 'Accept: application/json' \
  -H 'Content-Type: application/json' \
  -H 'Idempotency-Key: <key>' \
  -d '{}'

const response = await fetch('https://<your-url>/api/v2/sprints/1/actions/start', {
  method: 'POST',
  headers: {
    'Authorization': 'Bearer <token>',
    'Accept': 'application/json',
    'Content-Type': 'application/json',
    'Idempotency-Key': '<key>',
  },
  body: JSON.stringify({}),
});

use Illuminate\Support\Facades\Http;

$response = Http::withToken('<token>')
    ->acceptJson()
    ->withHeader('Idempotency-Key', '<key>')
    ->post('https://<your-url>/api/v2/sprints/1/actions/start', [
    ]);

import requests
response = requests.request(
    'POST',
    'https://<your-url>/api/v2/sprints/1/actions/start',
    headers={'Authorization': 'Bearer <token>', 'Accept': 'application/json', 'Content-Type': 'application/json', 'Idempotency-Key': '<key>'},
    json={},
)

Response

The shape of the response, with sample values.

{
  "data": {
    "id": 1,
    "project_id": 1,
    "name": "Sprint 14",
    "description": "…",
    "start_date": "2026-03-04",
    "end_date": "2026-03-04",
    "started_at": "2026-03-04T09:15:00Z",
    "completed_at": "2026-03-04T09:15:00Z",
    "is_active": false,
    "order": 1,
    "work_items_count": 1,
    "created_at": "2026-03-04T09:15:00Z"
  }
}

{
  "type": "https://developers.plnnrly.com/api/v2/problems/state-conflict",
  "title": "State conflict",
  "status": 409,
  "detail": "The target status is not reachable from this work item's current status.",
  "instance": "/api/v2/work-items/812/actions/transition",
  "request_id": "01K4B7Q9YV3PZ2N8T1E6M0XR4S",
  "conflict": {
    "reason": "illegal_transition",
    "from_workflow_status_id": 3,
    "to_workflow_status_id": 9
  }
}

{
  "type": "https://developers.plnnrly.com/api/v2/problems/precondition-failed",
  "title": "Precondition failed",
  "status": 412,
  "detail": "The record changed since the version named in If-Match. Re-read it and retry.",
  "instance": "/api/v2/work-items/812",
  "request_id": "01K4B7Q9YV3PZ2N8T1E6M0XR4S",
  "current_version": 12
}

3 more fields, listed under Response

The planned start_date and end_date are left alone (planning dates and running a sprint are independent), and order is not touched. At most one sprint per project may run at a time, so three states refuse with 409 state-conflict: a completed sprint (conflict.reason already_completed), a sprint that is already running (already_started), and a sprint whose project already has a different running sprint (already_started, with the blocking sprint named in the conflict member; complete it first). Returns the sprint in the detail view with a fresh ETag. Takes no request body.

Path parameters

sprintintegerRequired

The Sprint's numeric id.

Query parameters

Unknown parameters are refused with 400, naming the parameter.

viewstring

Which field set to render.

summarydetaildefault

Request headers

X-Request-Idstringpattern

A correlation id of your own. It is recorded in our logs next to the server's request id but never returned: the response header always carries the server's id. A value that does not match the pattern is discarded silently, never rejected.

If-Matchstring

The ETag a write is conditional on. A stale validator is 412 precondition-failed.

Idempotency-Keystring≤ 255

A caller-chosen key that makes this POST safe to retry. Replaying it returns the original response with Idempotency-Replayed: true.

Response 200

Returns a Sprint in the detail view.

Headers

ETag: A strong validator of exactly this representation.
Idempotency-Replayed: true when this response was replayed from a stored Idempotency-Key rather than produced by a new write.
RateLimit: The IETF httpapi-ratelimit-headers form of your remaining allowance on the tightest bucket this request touched.
RateLimit-Policy: The ceiling and window of that bucket, as <limit>;w=<seconds>.
X-Request-Id: The server-generated ULID correlating this response with our logs.

Every response also carries Cache-Control, Vary, X-Content-Type-Options, X-Plnnrly-Api-Version, X-RateLimit-Limit, X-RateLimit-Remaining, X-RateLimit-Reset. Headers and versioning