X402

Discover and call paid APIs using the X402 payment protocol with automatic USDC payments.

Install

npx promptshop add x402

Details

What This Skill Does

This skill enables users to discover, inspect, and call paid API endpoints using the X402 payment protocol. It facilitates searching the bazaar for services, checking payment requirements, and making paid requests with automatic USDC payment on Base. This is useful for developers integrating with paid APIs.

When to Use

Find a paid API service.
Check the price of an API endpoint.
Call an API with automatic USDC payment.
Search the bazaar for specific APIs.
Inspect the input schema of an API.
Discover new paid API services.

Key Features

Searches the bazaar for paid API endpoints.
Discovers payment requirements (price, method, schema).
Makes paid requests with automatic USDC payment.
Uses the npx awal@2.0.3 x402 commands.
Supports JSON output.
Caches search results locally.

Workflow

The typical x402 workflow is:

Find a service - Search the bazaar or get details for a known endpoint Check requirements - Inspect price, method, and input schema Make the request - Call the endpoint with automatic USDC payment

Commands

Search the Bazaar

Find paid services by keyword using BM25 relevance search:

npx awal@2.0.3 x402 bazaar search <query> [-k <n>] [--force-refresh] [--json]

Option	Description
-k, --top	Number of results (default: 5)
--force-refresh	Re-fetch resource index from CDP API
--json	Output as JSON

Results are cached locally at ~/. config/awal/bazaar/ and auto-refresh after 12 hours.

List Bazaar Resources

Browse all available resources:

awal x402 bazaar list [--network <network>] [--full] [--json]

Option	Description
--network	Filter by network (base, base-sepolia)
--full	Show complete details including schemas
--json	Output as JSON

Discover Payment Requirements

Inspect an endpoint's x402 payment requirements without paying:

awal x402 details <url> [--json]

Auto-detects the correct HTTP method (GET, POST, PUT, DELETE, PATCH) by trying each until it gets a 402 response, then displays price, accepted payment schemes, network, and input/output schemas.

Make a Paid Request

Call an x402 endpoint with automatic USDC payment:

awal x402 pay <url> [-X <method>] [-d <json>] [-q <params>] [-h <json>] [--max-amount <n>] [--json]

Option	Description
-X, --method	HTTP method (default: GET)
-d, --data	Request body as JSON string
-q, --query	Query parameters as JSON string
-h, --headers	Custom HTTP headers as JSON string
--max-amount	Max payment in USDC atomic units (1000000 = $1.00)
--correlation-id	Group related operations
--json	Output as JSON

Examples

Search for weather-related paid APIs

awal x402 bazaar search "weather"

Search with more results awal x402 bazaar search "sentiment analysis" -k 10

Check what an endpoint costs awal x402 details https://example. com/api/weather

Make a GET request (auto-pays) awal x402 pay https://example. com/api/weather

Make a POST request with body awal x402 pay https://example. com/api/sentiment -X POST -d '{"text": "I love this product"}'

Limit max payment to $0.10 awal x402 pay https://example. com/api/data --max-amount 100000

Browse all bazaar resources with full details awal x402 bazaar list --full

USDC Amounts

X402 uses USDC atomic units (6 decimals):

Atomic Units	USD
1000000	$1.00
100000	$0.10
50000	$0.05
10000	$0.01

Prerequisites

Search/Details: No authentication needed Pay: Must be authenticated (awal auth login ) with sufficient USDC balance (awal balance)

Error Handling

"Not authenticated" - Run awal auth login first "No X402 payment requirements found" - URL may not be an x402 endpoint "CDP API returned 429" - Rate limited; cached data will be used if available "Insufficient balance" - Fund wallet with USDC (awal balance to check)x402 Payment Protocol

Use the npx awal@2.0.3 x402 commands to discover, inspect, and call paid API endpoints using the X402 payment protocol. Payments are made in USDC on Base.