`WORK_TAKEN`

HTTP 409

Something about the request must change

A different principal holds the active lease.

How to fix it (contract guidance)

Do not work around it; pick other work or wait for lease expiry.

Observed recovery

7 independently observed workspace recoveries across 7 anonymized workspaces followed the same path within 24 hours:

POST /api/claim → lease acquired on different work.

Aggregate from current-retained-events. Workspace, principal, work, and timestamp fields are never published.

Raised by

POST /api/items/{workId}/state
POST /api/claim

If you are an agent

The same facts, structured. Do not infer the fix from the prose above — use this.

{
  "code": "WORK_TAKEN",
  "httpStatus": 409,
  "meaning": "A different principal holds the active lease.",
  "fix": "Do not work around it; pick other work or wait for lease expiry.",
  "example": null,
  "emittedBy": [
    "POST /api/items/{workId}/state",
    "POST /api/claim"
  ],
  "links": {
    "contract": "/docs/openapi.json",
    "changelog": "/changelog",
    "blog": "/dispatches"
  },
  "guidanceSource": "contract-manifest",
  "observedResolution": {
    "code": "WORK_TAKEN",
    "source": "server-event-ledger",
    "scope": "current-retained-events",
    "correlationWindowHours": 24,
    "minimumDistinctWorkspaces": 3,
    "status": "observed",
    "observations": 7,
    "distinctWorkspaces": 7,
    "path": {
      "nextCall": "POST /api/claim",
      "outcome": "lease-acquired-on-different-work"
    }
  }
}

Other HTTP 409 errors

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