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

# x402 Payments

> Pay-per-request market data APIs powered by x402 and settled in USDC on Base.

ELUUP provides pay-per-request market data APIs for developers and autonomous agents. Access is settled on-chain in USDC on Base, with no ELUUP account, subscription, or API key required.

Use this section to integrate the x402 APIs, understand pricing, and discover the available endpoints.

## Overview

This document is a developer reference for integrating with the ELUUP x402 API endpoints.

It covers:

* Client-side setup for calling x402-protected endpoints
* Available API endpoints, free and paid
* x402 payment requirements and pricing
* Request parameters and validation rules
* Successful response structures and field definitions
* Nullable fields
* HTTP status codes
* Application-level error structures
* How to read and debug a `402 Payment Required` response
* Request and response examples

This documentation is intended for developers and autonomous agents consuming the ELUUP APIs programmatically. No ELUUP account, subscription, or API key is required — access is pay-per-request, settled on-chain in USDC on Base.

***

## API Endpoints

| Method | Endpoint                | Payment |             Price |
| ------ | ----------------------- | ------- | ----------------: |
| `POST` | `/v1/token-signals`     | x402    |   `$0.05 / token` |
| `POST` | `/v1/token-prices`      | x402    |   `$0.03 / token` |
| `POST` | `/v1/signal-history`    | x402    |   `$0.05 / token` |
| `POST` | `/v1/token-win-rate`    | x402    |   `$0.03 / token` |
| `POST` | `/v1/token-avg-prices`  | x402    |   `$0.02 / token` |
| `POST` | `/v1/top-performers`    | x402    | `$0.06 / request` |
| `POST` | `/v1/aggregate-metrics` | x402    | `$0.06 / request` |
| `POST` | `/v1/supported-tokens`  | Free    |           `$0.00` |

<Warning>
  **Important:** The maximum batch size for all token-batch APIs is **5 tokens per request**, and every token in a batch must be **unique** (see [Duplicate Token Error](/x402/errors#duplicate-token-rejection)).
</Warning>

***

## x402 Payment Configuration

Paid APIs use the following x402 configuration.

| Property                    | Value                                                                                                                                     |
| --------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------- |
| Payment scheme              | `exact`                                                                                                                                   |
| Network                     | Base Mainnet                                                                                                                              |
| CAIP-2 Network ID           | `eip155:8453`                                                                                                                             |
| Payment asset               | USDC (`0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913`)                                                                                       |
| Payment recipient (`payTo`) | Server-configured. Always read the live value from the `accepts[].payTo` field of the `402` response — do not hardcode it in your client. |

The paid endpoints are protected by the x402 payment middleware. The `/v1/supported-tokens` endpoint is not included in the x402 payment middleware and is therefore free.

***

## Pricing

### Token-Batch APIs

The following APIs are priced per token:

* `/v1/token-signals`
* `/v1/token-prices`
* `/v1/signal-history`
* `/v1/token-win-rate`
* `/v1/token-avg-prices`

```text theme={null}
price = price_per_token × number_of_tokens
```

The maximum number of tokens per request is **5**, and duplicate identifiers within the same request are rejected before any payment is requested (no charge).

#### Token Signals — \$0.05/token

| Tokens |   Price |
| -----: | ------: |
|      1 | `$0.05` |
|      2 | `$0.10` |
|      3 | `$0.15` |
|      4 | `$0.20` |
|      5 | `$0.25` |

#### Token Prices — \$0.03/token

| Tokens |   Price |
| -----: | ------: |
|      1 | `$0.03` |
|      2 | `$0.06` |
|      3 | `$0.09` |
|      4 | `$0.12` |
|      5 | `$0.15` |

#### Signal History — \$0.05/token

| Tokens |   Price |
| -----: | ------: |
|      1 | `$0.05` |
|      2 | `$0.10` |
|      3 | `$0.15` |
|      4 | `$0.20` |
|      5 | `$0.25` |

#### Token Win Rate — \$0.03/token

| Tokens |   Price |
| -----: | ------: |
|      1 | `$0.03` |
|      2 | `$0.06` |
|      3 | `$0.09` |
|      4 | `$0.12` |
|      5 | `$0.15` |

#### Token Average Prices — \$0.02/token

| Tokens |   Price |
| -----: | ------: |
|      1 | `$0.02` |
|      2 | `$0.04` |
|      3 | `$0.06` |
|      4 | `$0.08` |
|      5 | `$0.10` |

### Fixed-Price APIs

#### Top Performers — \$0.06/request

The price does not depend on the `limit` value.

#### Aggregate Metrics — \$0.06/request

The price does not depend on any request parameters.

***

## Complete Pricing Reference

| API                     | Payment |         Pricing |        Maximum |
| ----------------------- | ------- | --------------: | -------------: |
| `/v1/token-signals`     | x402    |   `$0.05/token` |       5 tokens |
| `/v1/token-prices`      | x402    |   `$0.03/token` |       5 tokens |
| `/v1/signal-history`    | x402    |   `$0.05/token` |       5 tokens |
| `/v1/token-win-rate`    | x402    |   `$0.03/token` |       5 tokens |
| `/v1/token-avg-prices`  | x402    |   `$0.02/token` |       5 tokens |
| `/v1/top-performers`    | x402    | `$0.06/request` | `limit <= 300` |
| `/v1/aggregate-metrics` | x402    | `$0.06/request` |            N/A |
| `/v1/supported-tokens`  | Free    |         `$0.00` | `limit <= 500` |

***

**x402 docs:** [Overview](/x402) · [Quickstart](/x402/quickstart) · [Payment Flow](/x402/payment-flow) · [API Reference](/x402/api-reference) · [Errors & Troubleshooting](/x402/errors) · [Examples](/x402/examples)