> For the complete documentation index, see [llms.txt](https://fundable-finance.gitbook.io/docs/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://fundable-finance.gitbook.io/docs/api-reference.md).

# API reference

The package exposes three import boundaries:

```ts
import { createFundableClient } from "@fundable/sdk";
import { parseUnits, formatUnits, FundableError } from "@fundable/sdk/core";
import type { StellarFundableClientConfig } from "@fundable/sdk/stellar";
```

## Top-level client

`createFundableClient(config)` returns `StellarFundableClient` for `chain: "stellar"`. Its capability groups are:

| Property    | Availability                                      |
| ----------- | ------------------------------------------------- |
| `flows`     | Always present; `contracts.flow` is required.     |
| `router`    | Present when `contracts.router` is configured.    |
| `streamNft` | Present when `contracts.streamNft` is configured. |
| `paymaster` | Present when `contracts.paymaster` is configured. |

## Flow client

| Method                                                                    | Result                                               |
| ------------------------------------------------------------------------- | ---------------------------------------------------- |
| `create`                                                                  | Assembled transaction returning stream ID.           |
| `createAndDeposit`                                                        | Assembled transaction returning stream ID.           |
| `deposit`, `withdraw`, `pause`, `restart`, `adjustRate`, `refund`, `void` | Assembled state-changing transaction.                |
| `withdrawMax`, `refundMax`                                                | Assembled transaction returning the affected amount. |
| `getStream`                                                               | Normalized `FlowRecord`.                             |
| `getStatus`                                                               | Normalized `FlowStatus`.                             |
| Amount and debt getters                                                   | `bigint`.                                            |

## Router client

| Method         | Result                                                |
| -------------- | ----------------------------------------------------- |
| `createFlow`   | Assembled transaction returning Stream NFT token ID.  |
| `createLockup` | Assembled transaction returning Stream NFT token ID.  |
| `withdraw`     | Assembled transaction for an amount and token ID.     |
| `withdrawMax`  | Assembled transaction returning the withdrawn amount. |

## Stream NFT client

| Method          | Result                                   |
| --------------- | ---------------------------------------- |
| `ownerOf`       | Owner Stellar address.                   |
| `balanceOf`     | Number of Stream NFTs owned as `bigint`. |
| `getStreamData` | `{ tokenId, streamId, streamKind }`.     |
| `transfer`      | Assembled transfer transaction.          |

## Paymaster client

| Method              | Result                                             |
| ------------------- | -------------------------------------------------- |
| `isFeeTokenAllowed` | `boolean`.                                         |
| `forward`           | Assembled transaction returning the target result. |

`forward` requires the user, fee token and bounded fee amounts, expiration ledger, fee recipient, target contract, function name, and raw Soroban arguments. It is an advanced API: construct arguments from a reviewed target contract specification and never forward an arbitrary function supplied by an untrusted user.

## Core values

* `parseUnits(value, decimals)` converts a decimal string to exact `bigint` base units.
* `formatUnits(value, decimals)` formats base units without floating-point arithmetic.
* `toUnixSeconds(value, label?)` normalizes a `Date` or non-negative `bigint`.
* `CHAIN_FAMILIES`, `FLOW_STATUSES`, and `STREAM_KINDS` provide stable string constants.

## Errors

SDK validation and adapter failures use `FundableError`:

```ts
try {
  await fundable.flows.getStream("42");
} catch (error) {
  if (error instanceof FundableError) {
    console.error(error.code, error.chain, error.message);
  }
}
```

The stable error codes are `INVALID_ARGUMENT`, `INVALID_CONFIGURATION`, `UNSUPPORTED_CHAIN`, `UNSUPPORTED_CAPABILITY`, `SIMULATION_FAILED`, `TRANSACTION_FAILED`, and `RPC_UNAVAILABLE`. The underlying failure may be available as `error.cause`; do not display raw provider responses to end users without filtering sensitive data.