# List UTXOs

List unspent outputs held by one Bitcoin address on one network, with pagination and sorting.

Endpoint: GET /bitcoin/utxos
Version: 2.0.0
Security: Auth

## Security:

  - `Auth` (unknown)
    apiKey in header X-Api-Key scopes: api:address:read

## Query parameters:

  - `chain_gid` (string, required)
    Exactly one Bitcoin network. Repeated values are invalid.

  - `address` (string, required)
    Bitcoin address whose unspent outputs are listed, in its native format.

  - `limit` (integer)
    Maximum number of items to return.

  - `page` (integer)
    Page number for pagination.

  - `sort_by` (string)
    Field to sort results by. Use `-` prefix for descending order.

## Response 200:

  - `200` (unknown)
    Paginated list of unspent outputs held by the address.

## Response 200 fields (application/json):

  - `items` (array, required)
    List of unspent outputs.

  - `items.chain_gid` (string, required)
    Blockchain identifier in [CAIP-2](https://chainagnostic.org/CAIPs/caip-2) format.
Format: `{namespace}:{reference}`
- **namespace**: Ecosystem identifier (3-8 chars, lowercase)
- **reference**: Blockchain identifier within namespace (1-32 chars)

**Examples**:
- `eip155:1`: Ethereum mainnet
- `eip155:56`: BNB Smart Chain mainnet
- `eip155:137`: Polygon mainnet
- `bip122:000000000019d6689c085ae165831e93`: Bitcoin mainnet
- `tron:728126428`: Tron mainnet
    Example: eip155:1

  - `items.address` (string, required)
    Blockchain address in its native format.
**Format by network**:
- **EVM**: `0x` + 40 hex chars (normalized to [EIP-55](https://eips.ethereum.org/EIPS/eip-55) checksum on import)
- **Bitcoin**: P2PKH (1...), P2SH (3...), P2WPKH (bc1...)
- **Solana**: Base58, 32-44 chars
- **Tron**: Base58, starts with `T`
    Example: 0x8521E8b15eCEF4D4269Fded3E6694225E096959E

  - `items.txid` (string, required)
    Native transaction id of the chain (hash for EVM and Tron, txid for Bitcoin).
    Example: 0x1234567890abcdef1234567890abcdef1234567890abcdef1234567890abcdef

  - `items.vout_index` (integer, required)
    Output index within the transaction.
    Example: 0

  - `items.amount` (object, required)
    Asset amount in base units, plus a human-readable value when we know
the token's decimals.
    Example: {"base":"1000000000","formatted":"1.0"}

  - `items.amount.base` (string, required)
    Amount in the smallest asset unit.

  - `items.amount.formatted` (string)
    Human-readable amount.

  - `items.script_pubkey_hex` (string, required)
    Hex-encoded locking script of the address.
    Example: 0014751e76e8199196d454941c45d1b3a323f1433bd6

  - `items.block_number` (integer, required)
    Block number/height on the blockchain.
    Example: 18500000

  - `references` (object, required)
    Related objects included in the response, keyed by ID.

  - `references.blockchains` (object, required)
    Map of blockchains indexed by their CAIP-2 Chain GID.

  - `meta` (object, required)
    Pagination metadata returned on every list response. `page` and `limit` echo the values used to build this page (defaults are applied when the request omits them). `total` and `total_pages` reflect the full result set after any filters are applied.
    Example: {"limit":20,"page":1,"total":42,"total_pages":3}

  - `meta.limit` (integer, required)
    Page size used to build this response.

  - `meta.page` (integer, required)
    Index of the page returned, starting at 1.

  - `meta.total` (integer, required)
    Total number of items matching the request across all pages.

  - `meta.total_pages` (integer, required)
    Total number of pages available at the current `limit`.

## Response 400:

  - `400` (unknown)
    Bad request (e.g., missing or invalid fields). Invalid text may be reported as address.label_invalid, address.meta_invalid, public_key.label_invalid, invoice.comment_invalid, invoice.metadata_invalid.

## Response 400 fields (application/problem+json):

  - `type` (string, required)
    A URI that identifies the error type.
    Example: https://docs.vilna.io/apis/errors#internal-error

  - `title` (string, required)
    A short summary of the error type.
Use `detail` for information specific to this occurrence.
    Example: Bad Request

  - `status` (integer, required)
    The HTTP status code for this error.
Matches the status code of the HTTP response.
    Example: 400

  - `detail` (string)
    A human-readable explanation of what went wrong in this specific case.
May be localized.
    Example: The address is already assigned to another invoice

  - `instance` (string)
    A URI that identifies this specific error occurrence.
Include this value when contacting support.
    Example: /traces/0123456789abcdef0123456789abcdef

  - `code` (string, required)
    Stable machine-readable error code for programmatic error handling. Unlike the HTTP `status` or free-form `detail`, this code is guaranteed not to change between versions for a given error condition, so it is safe to branch on in client code. Defaults to `unspecified` when the server has not assigned a specific code.
    Example: blockchain.not_found

  - `fields` (array)
    List of invalid fields in the request.

  - `fields.name` (string, required)
    The name of the invalid field.
    Example: max_len

  - `fields.reason` (string, required)
    Why this field is invalid.
    Example: 32

## Response 401:

  - `401` (unknown)
    Missing or invalid authentication credentials.

## Response 401 fields (application/problem+json):

  - `type` (string, required)
    A URI that identifies the error type.
    Example: https://docs.vilna.io/apis/errors#internal-error

  - `title` (string, required)
    A short summary of the error type.
Use `detail` for information specific to this occurrence.
    Example: Bad Request

  - `status` (integer, required)
    The HTTP status code for this error.
Matches the status code of the HTTP response.
    Example: 400

  - `detail` (string)
    A human-readable explanation of what went wrong in this specific case.
May be localized.
    Example: The address is already assigned to another invoice

  - `instance` (string)
    A URI that identifies this specific error occurrence.
Include this value when contacting support.
    Example: /traces/0123456789abcdef0123456789abcdef

  - `code` (string, required)
    Stable machine-readable error code for programmatic error handling. Unlike the HTTP `status` or free-form `detail`, this code is guaranteed not to change between versions for a given error condition, so it is safe to branch on in client code. Defaults to `unspecified` when the server has not assigned a specific code.
    Example: blockchain.not_found

## Response 403:

  - `403` (unknown)
    Insufficient permissions.

## Response 403 fields (application/problem+json):

  - `type` (string, required)
    A URI that identifies the error type.
    Example: https://docs.vilna.io/apis/errors#internal-error

  - `title` (string, required)
    A short summary of the error type.
Use `detail` for information specific to this occurrence.
    Example: Bad Request

  - `status` (integer, required)
    The HTTP status code for this error.
Matches the status code of the HTTP response.
    Example: 400

  - `detail` (string)
    A human-readable explanation of what went wrong in this specific case.
May be localized.
    Example: The address is already assigned to another invoice

  - `instance` (string)
    A URI that identifies this specific error occurrence.
Include this value when contacting support.
    Example: /traces/0123456789abcdef0123456789abcdef

  - `code` (string, required)
    Stable machine-readable error code for programmatic error handling. Unlike the HTTP `status` or free-form `detail`, this code is guaranteed not to change between versions for a given error condition, so it is safe to branch on in client code. Defaults to `unspecified` when the server has not assigned a specific code.
    Example: blockchain.not_found

## Response 404:

  - `404` (unknown)
    Requested resource does not exist.

## Response 404 fields (application/problem+json):

  - `type` (string, required)
    A URI that identifies the error type.
    Example: https://docs.vilna.io/apis/errors#internal-error

  - `title` (string, required)
    A short summary of the error type.
Use `detail` for information specific to this occurrence.
    Example: Bad Request

  - `status` (integer, required)
    The HTTP status code for this error.
Matches the status code of the HTTP response.
    Example: 400

  - `detail` (string)
    A human-readable explanation of what went wrong in this specific case.
May be localized.
    Example: The address is already assigned to another invoice

  - `instance` (string)
    A URI that identifies this specific error occurrence.
Include this value when contacting support.
    Example: /traces/0123456789abcdef0123456789abcdef

  - `code` (string, required)
    Stable machine-readable error code for programmatic error handling. Unlike the HTTP `status` or free-form `detail`, this code is guaranteed not to change between versions for a given error condition, so it is safe to branch on in client code. Defaults to `unspecified` when the server has not assigned a specific code.
    Example: blockchain.not_found

## Response 422:

  - `422` (unknown)
    Request preconditions were not met.

## Response 422 fields (application/problem+json):

  - `type` (string, required)
    A URI that identifies the error type.
    Example: https://docs.vilna.io/apis/errors#internal-error

  - `title` (string, required)
    A short summary of the error type.
Use `detail` for information specific to this occurrence.
    Example: Bad Request

  - `status` (integer, required)
    The HTTP status code for this error.
Matches the status code of the HTTP response.
    Example: 400

  - `detail` (string)
    A human-readable explanation of what went wrong in this specific case.
May be localized.
    Example: The address is already assigned to another invoice

  - `instance` (string)
    A URI that identifies this specific error occurrence.
Include this value when contacting support.
    Example: /traces/0123456789abcdef0123456789abcdef

  - `code` (string, required)
    Stable machine-readable error code for programmatic error handling. Unlike the HTTP `status` or free-form `detail`, this code is guaranteed not to change between versions for a given error condition, so it is safe to branch on in client code. Defaults to `unspecified` when the server has not assigned a specific code.
    Example: blockchain.not_found

  - `fields` (array)
    List of fields that failed precondition validation.

  - `fields.name` (string, required)
    The name of the field that failed validation.
    Example: status

  - `fields.reason` (string, required)
    Why the precondition failed for this field.
    Example: Cannot transition from archived to active state

## Response 429:

  - `429` (unknown)
    Capacity or action cooldown exceeded.

## Response 429 fields (application/problem+json):

  - `type` (string, required)
    A URI that identifies the error type.
    Example: https://docs.vilna.io/apis/errors#internal-error

  - `title` (string, required)
    A short summary of the error type.
Use `detail` for information specific to this occurrence.
    Example: Bad Request

  - `status` (integer, required)
    The HTTP status code for this error.
Matches the status code of the HTTP response.
    Example: 400

  - `detail` (string)
    A human-readable explanation of what went wrong in this specific case.
May be localized.
    Example: The address is already assigned to another invoice

  - `instance` (string)
    A URI that identifies this specific error occurrence.
Include this value when contacting support.
    Example: /traces/0123456789abcdef0123456789abcdef

  - `code` (string, required)
    Stable machine-readable error code for programmatic error handling. Unlike the HTTP `status` or free-form `detail`, this code is guaranteed not to change between versions for a given error condition, so it is safe to branch on in client code. Defaults to `unspecified` when the server has not assigned a specific code.
    Example: blockchain.not_found

## Response 502:

  - `502` (unknown)
    Invalid upstream response or integration failure.

## Response 502 fields (application/problem+json):

  - `type` (string, required)
    A URI that identifies the error type.
    Example: https://docs.vilna.io/apis/errors#internal-error

  - `title` (string, required)
    A short summary of the error type.
Use `detail` for information specific to this occurrence.
    Example: Bad Request

  - `status` (integer, required)
    The HTTP status code for this error.
Matches the status code of the HTTP response.
    Example: 400

  - `detail` (string)
    A human-readable explanation of what went wrong in this specific case.
May be localized.
    Example: The address is already assigned to another invoice

  - `instance` (string)
    A URI that identifies this specific error occurrence.
Include this value when contacting support.
    Example: /traces/0123456789abcdef0123456789abcdef

  - `code` (string, required)
    Stable machine-readable error code for programmatic error handling. Unlike the HTTP `status` or free-form `detail`, this code is guaranteed not to change between versions for a given error condition, so it is safe to branch on in client code. Defaults to `unspecified` when the server has not assigned a specific code.
    Example: blockchain.not_found

## Response 503:

  - `503` (unknown)
    The operation is temporarily unavailable. Please try again later.

## Response 503 fields (application/problem+json):

  - `type` (string, required)
    A URI that identifies the error type.
    Example: https://docs.vilna.io/apis/errors#internal-error

  - `title` (string, required)
    A short summary of the error type.
Use `detail` for information specific to this occurrence.
    Example: Bad Request

  - `status` (integer, required)
    The HTTP status code for this error.
Matches the status code of the HTTP response.
    Example: 400

  - `detail` (string)
    A human-readable explanation of what went wrong in this specific case.
May be localized.
    Example: The address is already assigned to another invoice

  - `instance` (string)
    A URI that identifies this specific error occurrence.
Include this value when contacting support.
    Example: /traces/0123456789abcdef0123456789abcdef

  - `code` (string, required)
    Stable machine-readable error code for programmatic error handling. Unlike the HTTP `status` or free-form `detail`, this code is guaranteed not to change between versions for a given error condition, so it is safe to branch on in client code. Defaults to `unspecified` when the server has not assigned a specific code.
    Example: blockchain.not_found

## Response 504:

  - `504` (unknown)
    Shared request deadline exhausted.

## Response 504 fields (application/problem+json):

  - `type` (string, required)
    A URI that identifies the error type.
    Example: https://docs.vilna.io/apis/errors#internal-error

  - `title` (string, required)
    A short summary of the error type.
Use `detail` for information specific to this occurrence.
    Example: Bad Request

  - `status` (integer, required)
    The HTTP status code for this error.
Matches the status code of the HTTP response.
    Example: 400

  - `detail` (string)
    A human-readable explanation of what went wrong in this specific case.
May be localized.
    Example: The address is already assigned to another invoice

  - `instance` (string)
    A URI that identifies this specific error occurrence.
Include this value when contacting support.
    Example: /traces/0123456789abcdef0123456789abcdef

  - `code` (string, required)
    Stable machine-readable error code for programmatic error handling. Unlike the HTTP `status` or free-form `detail`, this code is guaranteed not to change between versions for a given error condition, so it is safe to branch on in client code. Defaults to `unspecified` when the server has not assigned a specific code.
    Example: blockchain.not_found

## Response default:

  - `default` (unknown)
    Unexpected error.

## Response default fields (application/problem+json):

  - `type` (string, required)
    A URI that identifies the error type.
    Example: https://docs.vilna.io/apis/errors#internal-error

  - `title` (string, required)
    A short summary of the error type.
Use `detail` for information specific to this occurrence.
    Example: Bad Request

  - `status` (integer, required)
    The HTTP status code for this error.
Matches the status code of the HTTP response.
    Example: 400

  - `detail` (string)
    A human-readable explanation of what went wrong in this specific case.
May be localized.
    Example: The address is already assigned to another invoice

  - `instance` (string)
    A URI that identifies this specific error occurrence.
Include this value when contacting support.
    Example: /traces/0123456789abcdef0123456789abcdef

  - `code` (string, required)
    Stable machine-readable error code for programmatic error handling. Unlike the HTTP `status` or free-form `detail`, this code is guaranteed not to change between versions for a given error condition, so it is safe to branch on in client code. Defaults to `unspecified` when the server has not assigned a specific code.
    Example: blockchain.not_found

## Response 400 examples:

  - `The request body contains malformed JSON` (unknown)

## Response 401 examples:

  - `The API service refused authentication` (unknown)

## Response 403 examples:

  - `The API key lacks the required permission` (unknown)

## Response 404 examples:

  - `The address does not exist in this project` (unknown)

  - `The invoice does not exist in this project` (unknown)

## Response 422 examples:

  - `A confirmed invoice cannot be cancelled` (unknown)

## Response 503 examples:

  - `The operation cannot be completed at present` (unknown)