How AI Agents Actually Pay Each Other — A Practical Guide

August 6, 2026 — 8 min read — by Iris @ minia2a

Here's something the whitepapers don't tell you: agent-to-agent payments work today. Not in a testnet. Not behind an API key. Real USDC on Base, real curl commands, real agents making real decisions about when to pay for data.

This guide skips the theory. You'll have an agent with a wallet, spending credits autonomously, in under 60 seconds. No MetaMask, no KYC, no npm install required.

Step 1: Give Your Agent a Wallet (10 seconds)

$ curl -X POST https://minia2a.uk/api/v1/register-simple \
  -H "content-type: application/json" \
  -d '{"name":"my-research-agent"}'

{
  "ok": true,
  "wallet": "0xf16F0882de08315B438E9f3a2Abfb2d2E5d94ECA",
  "credits": 500,
  "message": "Agent registered with 500 free credits."
}

That's it. Your agent now has a wallet address and 500 credits. Save the wallet address — you'll use it in every API call to identify your agent.

Step 2: Make Your First Paid API Call

Append ?wallet=YOUR_ADDRESS to any endpoint. Credits deduct automatically — 1 credit per typical call.

$ curl "https://minia2a.uk/x402/gas?wallet=0xf16F0882de08315B438E9f3a2Abfb2d2E5d94ECA"

{
  "baseFee": 0.042,
  "priorityFee": 0.01,
  "fastGas": 0.052,
  "timestamp": "2026-08-06T12:00:00Z",
  "_trial": {"credits_remaining": 499}
}

Look at the _trial.credits_remaining field in every response — your agent always knows how much budget it has left. There's also an X-Credits-Remaining HTTP header if your agent prefers headers over JSON parsing.

Step 3: Check Your Balance

$ curl "https://minia2a.uk/api/v1/credits?wallet=0xf16F0882de08315B438E9f3a2Abfb2d2E5d94ECA"

{
  "wallet": "0xf16F0882de08315B438E9f3a2Abfb2d2E5d94ECA",
  "name": "my-research-agent",
  "credits": 499
}

Step 4: Solve CAPTCHAs (The Real Killer Feature)

Your agent hits a CAPTCHA while scraping. Instead of failing, it delegates to minia2a:

$ curl -X POST "https://minia2a.uk/x402/proxy/x402-captcha-solve" \
  -H "content-type: application/json" \
  -d '{"sitekey":"6LeIxAcTAAAAAJcZVRqyHh71UMIEGNQ_MXjiZKhI","url":"https://example.com","wallet":"0xf16F0882de08315B438E9f3a2Abfb2d2E5d94ECA"}'

{
  "token": "03AFcWeA...",
  "solved": true,
  "_trial": {"credits_remaining": 494}
}

CAPTCHA solving costs 5 credits (vs 1 for data endpoints) because it uses real anti-captcha.com infrastructure. Your agent gets the solved token back and can continue its work. No API key, no anti-captcha account, no billing setup.

Step 5: Give Your Agent Memory

Agents are stateless by default. The recall/find/store endpoints give them persistent memory across sessions:

$ # Store something
$ curl "https://minia2a.uk/x402/store?content=Bitcoin+ETF+inflows+hit+$500M+on+Aug+5&wallet=0xf16F0882de08315B438E9f3a2Abfb2d2E5d94ECA"

{"ok":true,"id":"mem_abc123"}

$ # Find it later
$ curl "https://minia2a.uk/x402/find?q=Bitcoin+ETF+inflows&wallet=0xf16F0882de08315B438E9f3a2Abfb2d2E5d94ECA"

[{"content":"Bitcoin ETF inflows hit $500M on Aug 5","score":0.94,"id":"mem_abc123"}]

This is how agents build knowledge over time. Store findings, recall them in later sessions, build context without re-scraping everything.

Step 6: When Free Credits Run Out — Top Up

500 credits = ~100 basic API calls or ~100 CAPTCHA solves. When you need more:

$ # 1. Send USDC on Base to the platform wallet
$ #    Address: 0xf16F0882de08315B438E9f3a2Abfb2d2E5d94ECA
$ #    Network: Base (chain ID 8453)
$ #    Token: USDC (0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913)

$ # 2. Tell minia2a about the transaction
$ curl -X POST https://minia2a.uk/api/v1/buy-credits \
  -H "content-type: application/json" \
  -d '{"wallet":"0xf16F0882de08315B438E9f3a2Abfb2d2E5d94ECA","txHash":"0xYOUR_TX_HASH"}'

{
  "ok": true,
  "usdcReceived": 5,
  "creditsAdded": 1000,
  "totalCredits": 1495
}

Rate: 1 USDC = 200 credits. That's ~200 API calls for a dollar. A $5 top-up gives your agent 1,000+ calls.

Putting It All Together: A Real Agent Script

Here's a complete shell script your agent can use. Save it as agent-tools.sh:

#!/bin/bash
# agent-tools.sh — minia2a agent toolkit
# Usage: ./agent-tools.sh <command> [args...]

WALLET="0xf16F0882de08315B438E9f3a2Abfb2d2E5d94ECA"  # Your wallet
BASE="https://minia2a.uk"

balance() {
  curl -s "$BASE/api/v1/credits?wallet=$WALLET" | python3 -c "import sys,json; d=json.load(sys.stdin); print(f'{d[\"credits\"]} credits')"
}

gas() {
  curl -s "$BASE/x402/gas?wallet=$WALLET" | python3 -c "import sys,json; d=json.load(sys.stdin); print(f'Base: {d[\"baseFee\"]} gwei | Fast: {d[\"fastGas\"]} gwei')"
}

solve-captcha() {
  curl -s -X POST "$BASE/x402/proxy/x402-captcha-solve" \
    -H "content-type: application/json" \
    -d "{\"sitekey\":\"$1\",\"url\":\"$2\",\"wallet\":\"$WALLET\"}" | \
    python3 -c "import sys,json; d=json.load(sys.stdin); print(d.get('token','FAILED'))"
}

recall() {
  curl -s "$BASE/x402/recall?q=$(python3 -c "import sys,urllib.parse; print(urllib.parse.quote(sys.argv[1]))" "$1")&wallet=$WALLET" | \
    python3 -c "import sys,json; [print(r['content'][:200]) for r in json.load(sys.stdin)]"
}

store() {
  curl -s "$BASE/x402/store?content=$(python3 -c "import sys,urllib.parse; print(urllib.parse.quote(sys.argv[1]))" "$1")&wallet=$WALLET"
}

# Route command
case "$1" in
  balance) balance ;;
  gas) gas ;;
  captcha) solve-captcha "$2" "$3" ;;
  recall) recall "$2" ;;
  store) store "$2" ;;
  *) echo "Usage: $0 {balance|gas|captcha|recall|store} [args]" ;;
esac

Your agent now has a toolkit: ./agent-tools.sh gas, ./agent-tools.sh captcha SITEKEY URL, ./agent-tools.sh recall "Bitcoin price". Each call costs 1-5 credits, deducted automatically.

Why This Matters

The agent economy isn't science fiction. It's running right now:

• 299 services available via pay-per-call — crypto data, web scraping, CAPTCHA solving, AI inference, and more
• 8,800+ free trials served — agents are already discovering and testing APIs autonomously
• Real USDC settlement on Base — no testnet tokens, no demo mode
• No API keys — your wallet address IS your identity
• No onboarding — agents discover, trial, and pay without human intervention

The infrastructure giants are building the payment rails (Cloudflare Wallets, Coinbase SDK, Circle Agent Stack). The discovery layer — where agents find, compare, and trial APIs — is still wide open. That's where minia2a sits.

What Your Agent Can Do Right Now

A quick tour of what's available, all accessible with the same ?wallet= pattern:

Start Building

You don't need a whitepaper. You don't need a token sale. You need one curl command and your agent has a wallet:

curl -X POST https://minia2a.uk/api/v1/register-simple \
  -H "content-type: application/json" \
  -d '{"name":"your-agent-name"}'

That's it. Your agent can now pay for APIs autonomously. No human in the loop.

minia2a.uk — agent-to-agent API marketplace. 299 services, USDC on Base, 15 free trials per endpoint. No KYC. · Docs · API Catalog · Register