# Building and Returning

**`GET /trust-chains/{hash}`**

Builds and returns a full trustchain, tracing from a Verifiable Presentation (VP) document back to the root Verifiable Credential (VC).

**Authentication:** Bearer token required (`Authorization: Bearer <token>`)

**Permission:** `Permissions.AUDIT_TRUST_CHAIN_READ`

***

## Request

### Path Parameters

| Parameter | Type   | Required | Description                           |
| --------- | ------ | -------- | ------------------------------------- |
| `hash`    | string | Yes      | Hash or identifier of the VP document |

***

## Response

### Success Response

**Status:** `200 OK`

```json
{
  "chain": [
    {
      "id": "did:hedera:testnet:zHcDLGFNymFAJiMBKnpbHDgjvTn6yZnwkPPeFhtJBECH_0.0.4532001",
      "type": "VC",
      "tag": "create_application",
      "label": "Create Application",
      "schema": "StandardRegistry",
      "owner": "did:hedera:testnet:zHcDLGFNymFAJiMBKnpbHDgjvTn6yZnwkPPeFhtJBECH_0.0.4532001",
      "document": {}
    }
  ],
  "userMap": [
    {
      "did": "did:hedera:testnet:zHcDLGFNymFAJiMBKnpbHDgjvTn6yZnwkPPeFhtJBECH_0.0.4532001",
      "username": "example_user"
    }
  ]
}
```

| Field              | Type   | Description                                  |
| ------------------ | ------ | -------------------------------------------- |
| `chain`            | array  | Ordered list of documents from VP to root VC |
| `chain[].id`       | string | Document identifier or DID                   |
| `chain[].type`     | string | Document type: `VC`, `VP`, or `DID`          |
| `chain[].tag`      | string | Policy block tag that produced this document |
| `chain[].label`    | string | Human-readable label                         |
| `chain[].schema`   | string | Schema name                                  |
| `chain[].owner`    | string | DID of the document owner                    |
| `chain[].document` | object | The raw credential document                  |
| `userMap`          | array  | Mapping of DIDs to usernames                 |

### Error Responses

| Status                      | Description               |
| --------------------------- | ------------------------- |
| `401 Unauthorized`          | Missing or invalid token  |
| `403 Forbidden`             | Insufficient permissions  |
| `500 Internal Server Error` | Unexpected server failure |


---

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