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.
https://t.co/MBYcGF3wqX
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.
https://t.co/FNUdf49wrz
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
https://t.co/2oZ3Xnz4o9
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.
Live web search for agents, per call:
/api/search ($0.01): ranked results as clean JSON
/api/search-lite ($0.008): up to five results
/api/answer ($0.08): a model-backed answer grounded in live results, with citations
Pay over x402 or MPP.
The metered chat routes quote each request from its body: exact-BPE input plus your max_tokens, from $0.001 up to a $2 per-call cap.
Pay the quote over x402 exact, or authorize it as a ceiling with upto and settle actual usage. MPP clients get the same quote. Model-backed.
x402 on 12 chains: Base, Solana, Polygon, Arbitrum, Monad, Celo, Avalanche, Sei, Optimism, Stellar, Algorand (USDC) and Robinhood Chain (USDG). Gas is sponsored on EVM chains; hold only the stablecoin.
Plus MPP on Tempo, Base and Celo. GET /api/rails shows what is live.
Coordination primitives for agents that share state: /api/memory/incr ($0.001) is an atomic counter; /api/memory/cas ($0.001) writes only if the current value matches, so agents can hold a lock with a TTL.
Keyed to the paying wallet, over x402 or MPP's evm method.
Install the Agent402 MCP server (example for the claude CLI):
claude mcp add agent402 -s user -- npx -y agent402-mcp@latest
Set AGENT_KEY to pay USDC over x402, or use the proof-of-work tools with no wallet. The hosted connector takes MPP from mppx-wrapped clients.
Selling an API over x402? Listing is one POST /api/index/register with your origin. No account, no review queue.
The crawler reads your manifest at once and re-probes it every 30 minutes; probes are never paid calls. Speak MPP? The MPP marketplace registers you in one call too.
POST /v1/judge returns typed judgments your code can branch on: yes or no with a probability, a choice, or a score. $0.001 per call over x402 or MPP.
Model-backed, with three backends in a failover order, and every answer names the model that served it.
On x402 and MPP's evm method, settlement runs after the tool answers, and only for a status under 400. An error status cancels it, so no money moves on those rails.
A Tempo push payment is sent before the call, so a failure there is recorded as a refund owed.
agent402-tollbooth is open-source pay-per-crawl you host yourself. People browse free; known AI crawlers get a 402 and pay per request in USDC over x402 or MPP, or solve a proof-of-work.
MIT licensed and non-custodial: the money goes to your wallet.
No wallet? Pure-CPU tools take proof-of-work instead of money:
1. GET /api/pow/challenge?slug=hash
2. Find a nonce so sha256 of challenge:nonce has 16 leading zero bits
3. Resend with X-Pow-Solution: token:nonce
Add a wallet later; the same routes take x402 or MPP.