## Check iMessage availability

`POST /api-check-imessage-availability`

Check whether a phone number is reachable via iMessage before sending. Useful for routing logic or pre-qualifying contacts.

### Request body

- `phone` (string, required) — The phone number to check. Accepts many formats — we normalize to E.164.

### Status codes

- **200** — Phone checked successfully
- **400** — Invalid phone number format
- **401** — Missing or invalid API key
- **403** — Trial account probing a destination that is not verified on the shared line
- **409** — Trial account has no shared line provisioned
- **429** — Rate limit exceeded
- **500** — Internal server error

**Request — cURL**

```bash
curl -X POST https://api.tryprojectblue.com/api-check-imessage-availability \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "phone": "+15551234567"
  }'
```

**Response — 200 OK**

```json
{
  "normalizedPhone": "+15551234567",
  "isIMessageAvailable": true
}
```

**Response — 400**

```json
{
  "error": "Invalid phone number format (Not a valid phone number). Please use format +12345678901"
}
```

**Response — 409 — trial**

Trial accounts only: the destination is verified but no shared line is provisioned.

```json
{
  "error": "This trial account is not provisioned on a shared line"
}
```