Agent payments are easy to talk about and hard to see. So we built a page where you can watch them settle. Every little walker on screen is one paid API call, read straight from the chain as it lands. It wears the logo of the seller it paid and hops into the gate for its price: a tenth of a cent, a cent, a dime, a dollar, more. Two protocols, side by side: x402 on @base: USDC payments to sellers listed in public x402 discovery. MPP on @tempo: payments to the recipients MPP sellers name in their own 402 challenges. Filter to either one, switch between the last hour and the last day, and tap any walker to see the payment and its transaction, so you can check it yourself. Up top: payments per minute, USDC settled and distinct buyers. Along the bottom: every payment as it arrives, seller and price. No login, no sample data, no estimates. If it's on screen, it settled. A few things we cared about: It shows everyone, not just us. One walker is a payment to Agent402. Every other one is someone else building on x402 and MPP, getting paid by agents that never made an account. It runs as its own read-only service. No keys, no shared database, nothing in common with the Agent402 API. It reads public chain data and public seller listings, and that's all. It's open source with the rest of Agent402. Leave it open in a tab. It's oddly calming. live.agent402.tools

Record on chain what your agent acted on. POST /api/attest ($0.05) takes the settlement tx of a paid call and writes a Base attestation: tool, sha256 of the JSON response, payment, payer, time. Only the buyer's own EVM wallet can attest, over x402 or MPP's evm method.

MPP on Tempo settles natively, in bridged USDC or PathUSD. It is the first challenge in each 402 that offers it, so a stock mppx client holding Tempo funds pays there. Identity-bound and long-running routes leave it out; x402 and MPP's evm method pay those.

Don't know the slug? GET /api/find?q=pdf to markdown is free and returns ranked tools with route, price, input schema and a call-ready example. It fixes a one-letter typo (and says so) and marks near misses weak. Then pay the route over x402 or MPP.

Before you launch a paid API, buy from it. POST /api/seller-payability ($0.10) pays one real call to your endpoint and reports each leg: the 402 decoded, whether a stock client's signature was accepted, the receipt. Payable over x402 or MPP.

Small utilities agents call inside loops, $0.001 each or free with proof-of-work: html-to-markdown, json-schema-infer, cron-next, token-count, and jwt-decode (decoding only, no signature check). Paid calls settle over x402 or MPP.

Image utilities, deterministic and with no network call: image-resize ($0.001), image-thumbnail ($0.001), and image-convert ($0.005) between PNG, JPEG and BMP. All three take proof-of-work instead of money, or pay over x402 or MPP.

Retrying a paid x402 call? Send an Idempotency-Key header: the same key and the same payment credential replay the paid answer instead of settling again, and a repeat that lands while the first still runs gets 409 with Retry-After. Every 402 here offers x402 and MPP.

Gate a site without touching its code: run agent402-tollbooth as a reverse proxy. Set TOLLBOOTH_UPSTREAM, TOLLBOOTH_PAYTO and TOLLBOOTH_FACILITATOR_URL, then npx agent402-tollbooth. People pass free. Crawlers get one 402 that settles over x402 and carries MPP challenges.

Agent memory where the wallet is the account: POST /api/memory writes a key, GET reads it, $0.001 each. Values up to 64KB, optional TTL. /api/memory/grant ($0.002) shares it with another wallet. Pay from an EVM wallet over x402 or MPP's evm method.

One wallet, four request formats under /v1, compatible with OpenAI chat, OpenAI Responses, Anthropic Messages and Gemini clients. Set your SDK's base URL to Agent402 and pay per call over x402 or MPP. Flat tiers: nano $0.003, base $0.02, pro $0.10, premium $0.50. Model-backed.

Building an x402 client and getting refused? Point it at a real paid route here and read why: each refusal carries a reason, a hint in words and the kind of retry needed. MPP clients get WWW-Authenticate: Payment on the same response. agent402.tools/x402-test

A guard we just added: crypto-news caches a failed feed for a minute so a failing source is not re-fetched every call. Now, when every feed is a cached failure, older ones are fetched again first, so a retry after a blip recovers in seconds. $0.002 per call over x402 or MPP.

New tools, paid per call over x402 or MPP: dub: translate and speak, one call loop-gate: continue, stop or escalate a loop email-guard: hidden text and AI-aimed instructions in mail page-change: page changed? mcp-package-check: facts on an MCP package agent402.tools

Finished, cited reports an agent buys per call: deep research $0.60, company dossier $0.85, SEC filing report $0.85, fund 13F report $0.60, ticker pack $2.00. Model-backed, with a data appendix. Paid over x402 or MPP; people can buy the same reports by card.

Preview routes for questions about images, model-backed: /v1/judge/vision ($0.003): up to four images, answered as yes or no, a choice, a score or a box /v1/judge/locate ($0.002): find up to four things in one image, each with a probability and a box Paid over x402 or MPP.

Reading an x402 response: No PAYMENT-RESPONSE header: nothing settled. Receipt with success:false: refused, not charged. Receipt on a status under 400: charged and served. On MPP, a settled answer carries a signed Payment-Receipt header. Either way, check the headers you hold.

agent402-client: find a tool from a sentence, then call it. Free pure-CPU tools are paid with a built-in proof-of-work, no wallet. For wallet-only tools, hand it an x402 or MPP payment fetch. Spending caps and caching apply the same on both wires.

New x402 seller with no settlement history? The router can still pay you: after every proven seller for the task, capped at $0.01 a call on Base and Solana, at the wallet your live 402 names, flagged unproven on the receipt. MPP sellers list on the MPP marketplace.