Agenticpay

agenticpay

[Website](https://agenticpay-dev.github.io/) · Spend caps · npm

Get paid by AI agents. Open-source payment infrastructure for the MCP ecosystem - declare a price on any tool, agents pay in USDC over x402, settles on Solana in ~1.5 seconds.

No Stripe. No accounts. No API keys.

The full stack is here - SDK, CLI, paywall middleware, self-hosted x402 facilitator, and a live LLM agent demo. All TypeScript, MIT licensed.

Just want to test it? Point your mcp-server at our hosted devnet

facilitator: FACILITATOR_URL=https://agentpay-facilitator-e9b20a5fee6a.herokuapp.com

No setup needed.

Live demo

A real Claude Opus agent receives a task, decides which paid tools to use, pays autonomously via x402 micropayments on Solana, and answers the user.

$ pnpm --filter @agenticpay/two-agent-demo agent

Agent wallet: 3rHoEumCpH8EGrr6Lq2vBKeyec6h3yPRGj2nGG2FzEfX Server: http://localhost:4021 Facilitator: http://localhost:4022 ← our own Model: claude-opus-4-7 Task: Reverse the string 'agentpay rocks' and tell me how many words are in 'The quick brown fox jumps over the lazy dog'.

[turn 1] tool_use: reverse_string({"text":"agenticpay rocks"}) → paying $0.001 USDC ... ✓ paid + got result in 1596ms: {"result":"skcor yaptnega"} [turn 1] tool_use: word_count({"text":"The quick..."}) → paying $0.0005 USDC ... ✓ paid + got result in 1286ms: {"count":9}

Agent final answer:

1. Reversed string: skcor yaptnega
2. Word count: 9 words

=== payments summary === reverse_string $0.0010 USDC 1596ms word_count $0.0005 USDC 1286ms TOTAL $0.0015 USDC 2 calls

On-chain proof (Solana devnet):

• Settled by our self-hosted facilitator: EsqzTG8id...Bnku
• Earlier settle via x402.org: 2d2HcefgJ...vkqY

Why

The current AI agent stack assumes humans hold the credit card. That breaks the moment agents act on their own initiative - calling APIs, hiring sub-agents, paying for compute. You can't OAuth your way through it.

Stablecoin micropayments over HTTP fix it. agenticpay packages the missing ergonomics for the MCP ecosystem specifically: any tool can declare a price, any agent can pay it, and the whole pipeline - including the facilitator that actually submits the on-chain settlement - is open source and self-hostable.

Architecture

┌──────────────┐     1) HTTP request                    ┌─────────────┐

│ Claude / │ ────────────────────────────────────▶ │ mcp-server │ │ GPT agent │ 2) HTTP 402 + payment requirements │ (yours) │ │ │ ◀──────────────────────────────────── │ │ │ │ 3) signed USDC payload │ │ │ │ ────────────────────────────────────▶ │ │ └──────────────┘ └─────┬───────┘ │ verify+settle ▼ ┌──────────────────────┐ │ agenticpay facilitator │ │ (also yours, this │ │ repo, port 4022) │ └──────────┬───────────┘ │ submit ▼ Solana (USDC SPL, sub-cent fees)

You can also point mcp-server at the public x402.org/facilitator for testnet/devnet, or at Coinbase CDP for mainnet. We just made the self-hosted route easy.

Packages

Install

npm install @agenticpay/sdk           # Solana + USDC primitives

npm install -g @agenticpay/cli # agenticpay command npm install @agenticpay/mcp-server # paywalled HTTP server npm install @agenticpay/facilitator # self-hosted x402 facilitator npm install @agenticpay/eliza-plugin # Eliza plugin (Solana-native agents) npm install @agenticpay/ai-sdk # Vercel AI SDK paid tools npm install -g @agenticpay/mcp-bridge # MCP server for Claude Desktop / Cursor

Or clone the monorepo to get the live two-agent demo and edit-friendly templates (recommended for first run - see Quickstart below).

Use with Claude Code

This repo ships an Anthropic Skill at .claude/skills/agenticpay/SKILL.md. Copy it into your ~/.claude/skills/ to give Claude Code first-class context about agenticpay - it'll then walk you through monetizing an MCP server, generating tool routes, and verifying on-chain settlements without re-reading the README every time.

mkdir -p ~/.claude/skills

cp -r .claude/skills/agenticpay ~/.claude/skills/

Quickstart (devnet, ~5 minutes, free)

# 1. Install

pnpm install pnpm -r build

2. Generate a payer wallet, fund it on devnet

node packages/cli/dist/index.js wallet new node packages/cli/dist/index.js wallet show

→ fund SOL at https://faucet.solana.com (paste pubkey)

→ fund USDC at https://faucet.circle.com (Solana Devnet, same pubkey)

3. (option A - fastest) Use our hosted devnet facilitator. Skip step 4.

export FACILITATOR_URL=https://agentpay-facilitator-e9b20a5fee6a.herokuapp.com

3. (option B - fully self-hosted) Start your own facilitator (terminal 1)

pnpm --filter @agenticpay/facilitator dev

Note the printed feePayer address. It needs ~0.05 SOL devnet to cover fees.

Either airdrop or use the helper:

pnpm --filter @agenticpay/facilitator fund export FACILITATOR_URL=http://localhost:4022

4. Start the paywalled mcp-server (terminal 2)

PAY_TO= pnpm --filter @agenticpay/mcp-server dev

5. Run the live LLM agent demo (terminal 3, needs ANTHROPIC_API_KEY in .env)

pnpm --filter @agenticpay/two-agent-demo agent

Framework integrations

Drop-in templates for the most common AI agent stacks live under examples/:

See examples/README.md for the integration matrix.

Status

Pre-alpha. Devnet validated end-to-end. Mainnet config supported but requires funding the facilitator with real SOL and pointing at a mainnet-capable RPC (Helius, QuickNode, etc.).

Roadmap

• Devnet end-to-end demo (smoke + LLM agent)
• Self-hosted x402 facilitator (verify + settle, fee_payer abstraction)
• Real-world MCP server template (search, fetch, summarize, extract - instead of toy reverse_string)
• On-chain escrow for long-running tasks (Anchor program)
• Agent reputation registry on-chain
• Hosted facilitator service (agenticpay.com)

What's a facilitator?

If you've never seen x402 before: the facilitator is the trusted middleman that (1) verifies an agent's signed payment payload, (2) submits the USDC transfer on-chain, and (3) pays the SOL gas fees so the agent doesn't need any SOL - only USDC. Most MCP devs don't want to run their own; they point at a hosted one.

This repo ships a complete facilitator implementation. You can self-host it, fork it, audit it, or deploy it as a service for your own users.

What happens when a paid tool call fails?

Short version: a failed tool call is never charged. x402 settlement is an irreversible push, so the middleware is careful about *when* it settles:

1. Verify before execute. The payment payload (signature, funds, requirements match) is verified before your tool handler runs. Invalid payment → HTTP 402, the tool never executes.
2. Execute with a buffered response. The handler runs, but its response is held back - nothing is sent to the agent yet.
3. Settle only on success. If the handler responds with status ≥ 400, the middleware skips settlement entirely and just returns the error. The agent pays nothing for a failed call.
4. No result without payment. If on-chain settlement itself fails, the buffered tool result is discarded and the agent gets a payment error instead - the server never leaks a result it wasn't paid for.

What this doesn't cover: a tool that returns 200 OK with a junk answer is still charged - the protocol can't judge response quality. That's what keeps per-call prices micro ($0.0005–$0.001 in the demo): the worst case is capped at one call's price, and quality enforcement belongs to a reputation layer (see Roadmap) rather than the payment protocol.

License

MIT