> ## Documentation Index
> Fetch the complete documentation index at: https://docs.phala.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Get Receipt

> Fetch the signed receipt for a response, including the transparency event log.

## Endpoint

```bash theme={"system"}
GET https://inference.phala.com/v1/aci/receipts/{id}
```

This endpoint returns the canonical per-response proof. The receipt binds request and response hashes to the attested gateway and is signed by a key from the attestation report's published keyset.

Use the `x-receipt-id` header from an inference response, or use the response `id`.

## Parameters

<ParamField path="id" type="string" required>
  Receipt id (`rcpt-...`) or response id from `POST /v1/chat/completions`.
</ParamField>

## Example

```bash theme={"system"}
curl "https://inference.phala.com/v1/aci/receipts/$RECEIPT_ID" \
  -H "Authorization: Bearer <API_KEY>"
```

## Response

| Field                    | Type   | Description                                                 |
| ------------------------ | ------ | ----------------------------------------------------------- |
| `api_version`            | string | ACI version token, for example `aci/1`.                     |
| `receipt_id`             | string | Receipt id.                                                 |
| `chat_id`                | string | Chat or response id.                                        |
| `workload_id`            | string | Must match the attestation report you verified.             |
| `workload_keyset_digest` | string | Must match the attestation report you verified.             |
| `endpoint`               | string | Route served, for example `/v1/chat/completions`.           |
| `method`                 | string | HTTP method.                                                |
| `served_at`              | number | Unix timestamp.                                             |
| `event_log`              | array  | Ordered transparency events.                                |
| `signature`              | string | Signature over the receipt by a key in the attested keyset. |

### `event_log` entries

| Event                            | Key fields                                                                               |
| -------------------------------- | ---------------------------------------------------------------------------------------- |
| `request.received`               | `body_hash`                                                                              |
| `middleware.forwarded`           | `body_hash`                                                                              |
| `route.selected`                 | `target_route_id`                                                                        |
| `request.forwarded`              | `body_hash`                                                                              |
| `transparency.request_modified`  | Present when forwarded body differs from the received body.                              |
| `upstream.verified`              | `provider`, `model_id`, `result`, `required`, `session_id`, `channel_bindings`, `claims` |
| `response.received`              | `cleartext_hash`                                                                         |
| `transparency.response_modified` | Present when returned body differs from the provider response.                           |
| `response.returned`              | `cleartext_hash`, `wire_hash`                                                            |

```json theme={"system"}
{
  "api_version": "aci/1",
  "receipt_id": "rcpt-e0eefe63b3673e2a5984951f",
  "chat_id": "d3ad808b20a444c29e798db35f112033",
  "workload_id": "sha256:3def476b...",
  "workload_keyset_digest": "sha256:3eff0836...",
  "endpoint": "/v1/chat/completions",
  "method": "POST",
  "served_at": 1781588857,
  "event_log": [
    { "seq": 0, "type": "request.received", "body_hash": "sha256:111d08a5..." },
    { "seq": 2, "type": "route.selected", "target_route_id": "phala/qwen3.5-27b" },
    {
      "seq": 5,
      "type": "upstream.verified",
      "provider": "phala",
      "model_id": "phala/qwen3.5-27b",
      "result": "verified",
      "required": true,
      "session_id": "as_3681736b..."
    },
    { "seq": 7, "type": "response.returned", "wire_hash": "sha256:07703fb4..." }
  ],
  "signature": "..."
}
```

## Verifying the Receipt

1. Fetch and verify a fresh [Attestation Report](/phala-cloud/confidential-ai/confidential-model/api-reference/attestation).
2. Confirm `workload_id` and `workload_keyset_digest` match the attestation report.
3. Verify `signature` under a `receipt_signing_keys` entry from the attested keyset.
4. Confirm `request.received.body_hash` matches the request body you sent.
5. Confirm `response.returned.wire_hash` matches the response bytes you received.
6. Read `upstream.verified`. For a confidential response, `result` is `verified`, `required` is `true`, and `session_id` points to an attested session.

See [Verify a Response](/phala-cloud/confidential-ai/verify/verify-signature) for the full walkthrough.

## Legacy Alias

`GET /v1/signature/{id}` returns this same receipt inside a compatibility envelope for older clients.

## Related

<CardGroup cols={2}>
  <Card title="Attestation Report" icon="microchip" href="/phala-cloud/confidential-ai/confidential-model/api-reference/attestation" />

  <Card title="Get Session" icon="link" href="/phala-cloud/confidential-ai/confidential-model/api-reference/sessions" />
</CardGroup>