x402.pub
GitHub

Pay-per-call APIs
for AI agents

A curated marketplace of APIs that agents can discover, pay for, and use autonomously. No API keys. No subscriptions. No human in the loop.

Browse pluginsDevelopers

How it works

Install a plugin

Add the marketplace and install any plugin with one command in Claude Code.

Use the skill

Invoke the plugin's skill. Claude calls the x402-gated API under the hood.

Pay per call

Each API call is paid via x402 — fractions of a cent, settled on Base, Ethereum, or Solana via USDC.

Built for autonomous agents

AI agents shouldn't wait for a human to install tools. When an agent needs a capability, it should be able to find it, evaluate it, and pay for it — all on its own.

Discover by need

Agents query the discovery API to find plugins that match their current task — search by capability, category, or budget.

Pay and use instantly

No signup. No API key provisioning. The agent pays per call with x402 and gets data back in the same request.

Skills on demand

Agents gain capabilities as they need them. A coding agent that hits a weather problem acquires weather data. One that needs market prices gets market prices.

Discovery API

Agents can programmatically search the marketplace. Discovery is free — you only pay when you call the actual API.

GET /api/discover?q=weather&maxPrice=0.01

{
  "results": [{
    "name": "Weather Forecast",
    "pricePerCall": "$0.001",
    "endpoints": [{ "method": "GET", "path": "/api/x402/weather" }],
    "install": "/plugin install weather@x402-pub"
  }],
  "count": 1
}

Trusted by design

When agents autonomously acquire capabilities, security is everything. Every plugin on x402.pub is reviewed, every developer is registered, and you control exactly what your agents can access.

Manual review

Every plugin is tested for correctness, security, and reliability before listing. No auto-approve, no spam.

Registered developers

Developers pay an annual fee to publish. This filters for serious, accountable API authors with skin in the game.

Access policies

Allowlist specific plugins, categories, or authors. Blocklist what you don't want. Set spending caps. You decide what your agents can reach.

Security reviewed

Plugins are checked for data exfiltration, prompt injection, excessive permissions, and wallet abuse before they go live.

Access policies

Control what your agents can discover and use. Pass a policy to the discovery API to enforce allowlists, blocklists, and spending limits.

// Only allow Data plugins, block a specific one, cap spend
{
  "name": "production",
  "allow": { "categories": ["Data"], "authors": ["x402-pub"] },
  "block": { "plugins": ["untrusted-plugin"] },
  "maxPricePerCall": 0.01,
  "maxSessionSpend": 1.00
}

Add the marketplace to Claude Code:

/plugin marketplace add https://x402.pub/api/marketplace.json