> For the complete documentation index, see [llms.txt](https://docs.stacks.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.stacks.co/reference/stacks.js/stacks-bitcoin-staking/fetch/fetchbond.md).

# fetchBond

Reads a protocol bond's configuration from the pox-5 `protocol-bonds` map, or returns `undefined` if `setup-bond` has not been called for that index.

***

### Usage

```ts
import { fetchBond } from '@stacks/bitcoin-staking';

const bond = await fetchBond({ bondIndex: 1, network: 'mainnet' });

if (bond) {
  bond.targetRateBps; // target rate in basis points
  bond.earlyUnlockBytes; // hex, pass to buildLockScript or fetchConstructLockupScript
}
```

#### Notes

* Reads the [`protocol-bonds`](https://github.com/stacks-network/stacks-core/blob/10474cdec9f9c0bdf05841b58cffc89cdad87a9b/stackslib/src/chainstate/stacks/boot/pox-5.clar#L109-L128) map through the node's `/v2/map_entry` endpoint. [fetchProtocolBond](/reference/stacks.js/stacks-bitcoin-staking/fetch/fetchprotocolbond.md) returns the same data through the `get-protocol-bond` read-only.
* The result has no start height or first reward cycle. Both follow from `bondIndex` and the PoX parameters: compute them with [bondPeriodToBurnHeight](/reference/stacks.js/stacks-bitcoin-staking/cycles/bondperiodtoburnheight.md) and [bondPeriodToRewardCycle](/reference/stacks.js/stacks-bitcoin-staking/cycles/bondperiodtorewardcycle.md).
* `earlyUnlockBytes` is the bond's early-unlock subscript as a hex string without a `0x` prefix. It is one of the inputs to the L1 lockup script: see [buildLockScript](/reference/stacks.js/stacks-bitcoin-staking/script/buildlockscript.md).
* A non-2xx response, or a response without `data`, throws an `Error` whose message starts with `Error fetching map entry for map "protocol-bonds"`.

[**Reference Link**](https://github.com/stx-labs/stacks.js/blob/6101c99efe5a9616ce7e16cef68e28fd10676e7e/packages/bitcoin-staking/src/fetch.ts#L243-L271)

***

### Signature

```ts
function fetchBond(
  opts: { bondIndex: number } & NetworkClientParam
): Promise<Bond | undefined>;
```

`opts` is a [NetworkClientParam](/reference/stacks.js/stacks-network/network/networkclientparam.md) plus `bondIndex`.

***

### Returns

`Promise<Bond | undefined>`

Resolves to a [Bond](/reference/stacks.js/stacks-bitcoin-staking/types/bond.md), or `undefined` when the map has no entry for `bondIndex`.

***

### Parameters

#### opts.bondIndex (required)

* **Type**: `number`

Index of the protocol bond, the map key.

#### opts.network (optional)

* **Type**: `StacksNetworkName | StacksNetwork`

The network to query: a name such as `'mainnet'` or `'testnet'`, or a [StacksNetwork](/reference/stacks.js/stacks-network/network/stacksnetwork.md) object. Defaults to `'mainnet'`.

#### opts.client (optional)

* **Type**: `{ baseUrl?: string; fetch?: FetchFn }`

Overrides the API base URL or the `fetch` function, for example to query your own node. Fields you set replace the network's defaults.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://docs.stacks.co/reference/stacks.js/stacks-bitcoin-staking/fetch/fetchbond.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.