> ## Documentation Index
> Fetch the complete documentation index at: https://t2z.d4mr.com/llms.txt
> Use this file to discover all available pages before exploring further.

# API Reference

> Complete reference for all t2z functions

This section documents all functions available in the t2z SDKs. The API is consistent across all platforms (TypeScript, Go, Kotlin) with language-appropriate naming conventions.

## Function Overview

### Transaction Construction

| Function                                                    | Description                            |
| ----------------------------------------------------------- | -------------------------------------- |
| [`propose_transaction`](/api-reference/propose-transaction) | Create a PCZT from inputs and payments |
| [`inspect_pczt`](/api-reference/inspect-pczt)               | Get detailed info about a PCZT         |

### Signing

| Function                                                          | Description                          |
| ----------------------------------------------------------------- | ------------------------------------ |
| [`get_sighash`](/api-reference/get-sighash)                       | Get the sighash for external signing |
| [`append_signature`](/api-reference/append-signature)             | Add a signature to the PCZT          |
| [`sign_transparent_input`](/api-reference/sign-transparent-input) | Sign with an in-memory private key   |

### Proving & Finalization

| Function                                                        | Description                 |
| --------------------------------------------------------------- | --------------------------- |
| [`prove_transaction`](/api-reference/prove-transaction)         | Generate Orchard proofs     |
| [`verify_before_signing`](/api-reference/verify-before-signing) | Verify PCZT matches request |
| [`finalize_and_extract`](/api-reference/finalize-and-extract)   | Extract final transaction   |

### Utilities

| Function                                            | Description                    |
| --------------------------------------------------- | ------------------------------ |
| [`parse_pczt`](/api-reference/parse-serialize)      | Parse PCZT from bytes          |
| [`serialize_pczt`](/api-reference/parse-serialize)  | Serialize PCZT to bytes        |
| [`prebuild_proving_key`](/api-reference/utilities)  | Pre-build the proving key      |
| [`is_proving_key_ready`](/api-reference/utilities)  | Check if proving key is cached |
| [`generate_test_address`](/api-reference/utilities) | Generate test Orchard address  |
| [`generate_test_keypair`](/api-reference/utilities) | Generate test keypair          |
| [`version`](/api-reference/utilities)               | Get library version            |

## Naming Conventions

The API uses consistent naming across platforms with language-appropriate conventions:

| TypeScript             | Go                   | Kotlin               |
| ---------------------- | -------------------- | -------------------- |
| `propose_transaction`  | `ProposeTransaction` | `proposeTransaction` |
| `get_sighash`          | `GetSighash`         | `getSighash`         |
| `WasmTransparentInput` | `TransparentInput`   | `TransparentInput`   |

## Error Handling

<Tabs>
  <Tab title="TypeScript">
    Functions throw `Error` on failure:

    ```typescript theme={null}
    try {
      const pczt = t2z.propose_transaction(...);
    } catch (err) {
      console.error('Failed:', err.message);
    }
    ```
  </Tab>

  <Tab title="Go">
    Functions return `error`:

    ```go theme={null}
    pczt, err := t2z.ProposeTransaction(...)
    if err != nil {
        log.Fatal(err)
    }
    ```
  </Tab>

  <Tab title="Kotlin">
    Functions throw exceptions:

    ```kotlin theme={null}
    try {
        val pczt = proposeTransaction(...)
    } catch (e: T2zException) {
        println("Failed: ${e.message}")
    }
    ```
  </Tab>
</Tabs>

## Type Reference

### TransparentInput

Represents a transparent UTXO to spend.

| Field          | Type       | Description                           |
| -------------- | ---------- | ------------------------------------- |
| `pubkey`       | bytes (33) | Compressed secp256k1 public key       |
| `prevoutTxid`  | bytes (32) | Transaction ID (little-endian)        |
| `prevoutIndex` | uint32     | Output index                          |
| `value`        | uint64     | Value in zatoshis                     |
| `scriptPubkey` | bytes      | P2PKH scriptPubkey                    |
| `sequence`     | uint32?    | Sequence number (default: 0xffffffff) |

### Payment

Represents a payment output.

| Field     | Type    | Description                               |
| --------- | ------- | ----------------------------------------- |
| `address` | string  | Unified or transparent address            |
| `amount`  | uint64  | Amount in zatoshis                        |
| `memo`    | bytes?  | Memo for shielded outputs (max 512 bytes) |
| `label`   | string? | Display label                             |

### ExpectedTxOut

For verification, represents an expected output.

| Field     | Type   | Description                 |
| --------- | ------ | --------------------------- |
| `address` | string | Expected address            |
| `amount`  | uint64 | Expected amount in zatoshis |

### PcztInfo

Result of `inspect_pczt`, contains transaction details.

| Field                      | Type   | Description                        |
| -------------------------- | ------ | ---------------------------------- |
| `expiry_height`            | uint32 | Transaction expiry block           |
| `transparent_inputs`       | array  | Input details                      |
| `transparent_outputs`      | array  | Transparent output details         |
| `orchard_outputs`          | array  | Orchard output details             |
| `total_input`              | uint64 | Sum of input values                |
| `total_transparent_output` | uint64 | Sum of transparent outputs         |
| `total_orchard_output`     | uint64 | Sum of Orchard outputs             |
| `implied_fee`              | uint64 | Calculated fee                     |
| `num_orchard_actions`      | uint32 | Number of Orchard actions          |
| `all_inputs_signed`        | bool   | Whether all inputs have signatures |
| `has_orchard_proofs`       | bool   | Whether proofs are present         |