Agents that pay their own way.
Working examples of AI agents that hit a paywall, settle it in-band, and keep going — no human in the loop. Nevermined is payment-protocol-independent — these demos span x402, MCP and MPP. Every tutorial is one page: what you'll learn, how it works, the code, and a panel where you run the real payment handshake yourself.
POSTPOST /research "EV market in Europe"
402Payment Required · plan: card-delegation
PAYpayment token · visa *4242
200OK · payment-response: settled
settled · 5 credits · one round-trip · zero clicks
Featured live demo
Freemium research agent, gated by x402
Chat for free to learn what it does; it charges only when it actually runs the research. The paywall sits inside the tool, not the route.
Catalog
3What's in the Catalog?
The half that comes before payment: the same live catalog of pay-per-use AI agents, read three ways — by eye, by an agent, and by a crawler. Public, unauthenticated, and free to read.
Song From the Headlines
An agent turns today's #1 tech headline into a finished song and album cover — discovering four services in the Nevermined Catalog and paying each one itself, across two blockchains, for about 16 cents. Zero human clicks.
Diligence in a Box
One prompt → a VC-grade investment memo on a startup. The agent finds and pays each data source through the Router itself — company overview, founder deep-dive, hiring momentum, SEC filings, web research. About 49 cents, zero clicks.
x402 HTTP
2Protect an Express agent with x402
A minimal Express server whose /ask endpoint is gated by the Nevermined payment middleware — one line per route.
The same paywall, on FastAPI
A minimal FastAPI server with a payment-protected /ask endpoint using the payments-py SDK and ASGI middleware.
MCP
2Paywall MCP tools, resources & prompts
A minimal MCP server exposing a weather.today tool, a weather://today resource and a weather.ensureCity prompt — all protected with credit-based access via the x402 v2 in-band MCP transport.
The MCP paywall, in Python
The Python equivalent of the Weather MCP server, built on FastMCP with the payments-py SDK — same tool, resource and prompt, same x402 v2 in-band transport.
LangChain
3Gate one LangChain tool with @requires_payment
The minimal case: a single LangChain/LangGraph tool gated by Nevermined payments. No HTTP layer, no 402 round-trip — the buyer threads a token in-process.
A paid tool inside a subagent
A Deep Agents market-research agent where the paid capability lives inside a subagent. The x402 token survives the task() delegation hop, so @requires_payment needs no changes.
Every call is paid: route-level middleware
Deploy a LangGraph agent to LangSmith Deployment and gate its runs/wait endpoint with the Nevermined x402 flow — a single env file plus four lines of glue.