Claude Code Auto Mode:
The Agent API Guide

Claude Code auto mode means your agent can approve its own tool calls — including paying for external API calls with real money. If your agent needs a captcha solved, a web page scraped, a token audited, or a screenshot taken, it can discover the service, try it for free, and pay for it — all without asking you.

This guide covers the practical "how": real endpoints, real prices, real curl commands. No theory. No fluff.

The 30-Second Version

Real Endpoints You Can Try Right Now

All prices in USDC. All endpoints support 8 chains (Base, Cloudflare, Celo, Polygon, BSC, Injective, Circle, Algorand). Every one has 15 free trial calls — no wallet needed.

Full directory: minia2a.uk/discover-new.html — 1,087 endpoints across 18 categories. Sorted by: AI, crypto, web, security, data, finance, and more.

The 3-Curl Walkthrough

Step 1: Discover what's available

curl -s https://minia2a.uk/api/services | jq '.services[:3] | .[] | {name, category, tier}'

Returns a catalog of services. Your agent filters by category, price, or endpoint name.

Step 2: Probe a service (no payment)

curl -sI "https://minia2a.uk/x402/web-scrape?probe=1"

Returns HTTP 402 with machine-readable headers:

HTTP/1.1 402 Payment Required
x-402-amount: 50
x-402-chain: base
x-402-token: USDC
x-402-recipient: 0xf16F...ECA
x-402-facilitator: https://facilitator.payai.network

Your agent reads these headers and knows exactly how much to pay, on what chain, in what token, to whom.

Step 3: Try for free (15 calls, no wallet)

curl -s "https://minia2a.uk/x402/web-scrape?url=https://example.com" \
  -H "X-Trial: true"

The trial response includes:

{
  "result": "<extracted content>",
  "_trial": {
    "remaining": 14,
    "total": 15,
    "register": "POST /api/v1/register-simple {name}",
    "credits": "Register to get 500 free credits"
  }
}

15 free calls per endpoint. 258 of 1,087 services have trial enabled. Your agent can test a service thoroughly before committing a single cent.

Auto Mode + Agent Budget: The Killer Combo

{
  "daily_limit_usdc": 5.00,
  "max_per_call_usdc": 1.00,
  "allowlist": ["minia2a.uk", "x402.org"]
}

At current minia2a prices ($0.001–$0.02/call), a $5 daily budget buys 250–5,000 API calls per day. Your agent can scrape the web, solve captchas, audit tokens, and screenshot pages — all autonomously, all within budget.

Your API Auto-Mode Checklist

The Architecture: How Agent Payments Actually Work

┌─────────────┐     ┌──────────────┐     ┌─────────────┐
│  Your Agent  │────▶│  Discovery   │────▶│  API Server  │
│  (CC auto)   │     │  (minia2a)   │     │  (seller)    │
└──────┬───────┘     └──────┬───────┘     └──────┬───────┘
       │                    │                    │
       │  1. "Find me a     │                    │
       │     captcha solver"│                    │
       │───────────────────▶│                    │
       │                    │                    │
       │  2. Here are 3,    │                    │
       │     cheapest first │                    │
       │◀───────────────────│                    │
       │                    │                    │
       │  3. GET /x402/captcha-solve             │
       │────────────────────────────────────────▶│
       │                    │                    │
       │  4. 402 Payment Required                │
       │     x-402-amount: 10                    │
       │◀────────────────────────────────────────│
       │                    │                    │
       │  5. Signs USDC transfer                 │
       │     Retries with X-Payment header       │
       │────────────────────────────────────────▶│
       │                    │                    │
       │  6. 200 OK + result                     │
       │◀────────────────────────────────────────│
       │                    │                    │

What Makes a 402 Response "Machine-Readable"

An autonomous agent can't read your HTML pricing page. It reads headers. Here's the minimum viable 402:

HTTP/1.1 402 Payment Required
x-402-amount: 10           # in USDC cents (10 = $0.10)
x-402-chain: base           # settlement chain
x-402-token: USDC           # settlement asset
x-402-recipient: 0x...      # where money goes
x-402-facilitator: https://  # who settles the tx

Without these headers, the agent sees "402 Payment Required" and... stops. It doesn't know how much, on what chain, in what token, to whom. Headers are the API for the API payment.

Why Trial-First Matters for Auto Mode

One Command to Get Started

curl -s https://minia2a.uk/api/services | \
  jq '.services[] | select(.category == "ai" or .category == "web" or .category == "crypto") | {name, category}'

Paste that into your terminal. Your agent can do the same — programmatically. That's the point.

Published August 11, 2026. Service prices and availability verified at time of writing via live endpoint probes. Auto mode goes default Aug 14 per Anthropic announcement.