{
  "description": "Every field populated",
  "submission": {
    "spec_version": "0.1",
    "type": "unhelpful_error",
    "goal": "Export all contacts created last week to the user's CRM",
    "message": "POST /contacts/export returned 400 with body {\"error\":\"bad request\"} and no hint about which field was wrong",
    "endpoint": "/contacts/export",
    "method": "POST",
    "outcome": "degraded",
    "workaround": true,
    "workaround_description": "Bisected the filter object until the request succeeded; created_after must be a date, not a datetime",
    "expected": "An error naming the invalid field and the accepted format",
    "suggestion": "Return {\"error\":{\"field\":\"created_after\",\"expected\":\"YYYY-MM-DD\"}}",
    "request_id": "req_8f2c1a",
    "session_id": "sess_42",
    "agent": {
      "name": "crm-sync-agent",
      "version": "1.4.0",
      "model": "claude-opus-5",
      "framework": "claude-agent-sdk"
    },
    "evidence": {
      "status_code": 400,
      "request": {
        "filter": {
          "created_after": "2026-09-21T00:00:00Z"
        }
      },
      "response_excerpt": "{\"error\":\"bad request\"}"
    },
    "metadata": {
      "retries": 3,
      "locale": "en-GB"
    }
  }
}