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

# Overview

> Retrieve cryptographic attestations for policy-compliant transactions

## API Workflow

The Predicate API evaluates transactions against your configured policies and returns cryptographic attestations for onchain verification.

1. Submit transaction details to `/v1/task`
2. Receive a signed `PredicateMessage` if compliant
3. Embed the attestation in your transaction calldata
4. Your smart contract verifies the attestation using `PredicateClient.sol`

## Request Format

```json theme={null}
{
  "from": "0x1234567890123456789012345678901234567890",
  "to": "0xabcdef1234567890123456789012345678901234",
  "data": "0x...",
  "msg_value": "0",
  "chain_id": 1
}
```

## Response Format

```json theme={null}
{
  "is_compliant": true,
  "signers": ["0xDAc74b6f9B3609E914c924eB87Adff87A30fcDf6"],
  "signature": ["0x35e593a668ec29bab179b2b0a7f83199c2ff58144..."],
  "expiry_block": 1752704559,
  "task_id": "9b1446bd-31d8-42d7-8890-61e5130d73b4"
}
```

## Authentication

Include your API key in the request header:

```bash theme={null}
x-api-key: YOUR_API_KEY
```

Generate keys in the [Predicate Dashboard](https://app.predicate.io).

## Base URLs

* **Production**: `https://api.predicate.io/v1`
* **Staging**: `https://staging.api.predicate.io/v1`