curl -sS -X POST https://app.opentrain.ai/api/public/v1/proposals/<PROPOSAL_ID>/hire \
  -H "Authorization: Bearer $OT_API_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "milestone": {
      "name": "First labeling batch",
      "description": "Label the first 5,000 posts per the guidelines",
      "amount": 300,
      "dueDate": "2026-07-01"
    }
  }'

opentrain proposals hire --proposal-id <PROPOSAL_ID> \
  --amount 300 \
  --milestone-name "First labeling batch" \
  --milestone-description "Label the first 5,000 posts per the guidelines" \
  --due-date 2026-07-01 --json

{
  "proposalId": "<PROPOSAL_ID>",
  "milestone": {
    "name": "First labeling batch",
    "description": "Label the first 5,000 posts per the guidelines",
    "amount": 300,
    "dueDate": "2026-07-01"
  }
}

{
  "approval": {
    "id": "<APPROVAL_ID>",
    "type": "proposal_hire",
    "status": "pending",
    "contractId": null,
    "milestoneId": null,
    "jobId": "<JOB_ID>",
    "proposalId": "<PROPOSAL_ID>",
    "approvalUrl": "https://app.opentrain.ai/approvals/<APPROVAL_ID>",
    "expiresAt": "2026-06-15T10:00:00.000Z",
    "resolvedAt": null,
    "result": null,
    "createdAt": "2026-06-12T10:00:00.000Z"
  },
  "message": "Hire request recorded. A signed-in human must confirm this approval in the OpenTrain app before the freelancer is hired and any money moves."
}

{
  "error": "No payment method on file. A human must add a card or credits in the OpenTrain app before a hire can be requested.",
  "code": "CONFLICT",
  "requestId": "<REQUEST_ID>",
  "details": {
    "proposalId": "<PROPOSAL_ID>",
    "reason": "payment_method_required",
    "billingUrl": "https://app.opentrain.ai/employer-settings?tab=billing"
  }
}