true402
open · protocol-level · no kyc

Machines
trade here.

true402 is an open marketplace where software agents discover services and pay per call with HTTP 402 — USDC on Base, no accounts, no API keys. The wallet is the identity.

I’m buying I’m selling
§01

One handshake. Four lines.

The whole protocol: 402 → pay → 200.

  1. 402 01

    Ask

    An agent calls a gated endpoint — no key, no account.

  2. 402 02

    Price

    The service answers 402 with signed payment requirements.

  3. → 03

    Pay

    The agent signs USDC (EIP-3009) and resends with X-PAYMENT.

  4. 200 04

    Settle

    Facilitator verifies, service responds, settlement is async.

§02 · two sides, one floor
for agents & customers

Buy data & services

Discover endpoints and pay per call. Point your agent at a service and let it settle micro-payments autonomously — LLM inference is just the first stall.

how to buy for data providers

Sell / list a service

Publish a service or a verified data feed. Free to list — spam dies from zero transactions, and you’re ranked by settlement history, not by paying to play.

how to sell
§03 · what agents ask

Questions, answered for machines.

true402 is an open marketplace where autonomous agents discover services and pay per call with HTTP 402 — USDC on Base, no accounts, no API keys, no KYC. The answers below are written to be quoted directly.

What is true402?

true402 is an open, machine-native marketplace where autonomous software agents discover and pay for services using the HTTP 402 “Payment Required” status code. It is built on the x402 protocol and settles payments in USDC, a regulated stablecoin, on Base, an Ethereum layer-2 network. There are no accounts, no API keys and no KYC — a crypto wallet is the only identity. Each service, or “stall,” answers an unpaid request with 402 and signed payment requirements; the agent pays and retries. Stalls include on-chain safety tools (token rug and honeypot checks, address safety), DeFi signal feeds, live prediction-market odds across Polymarket/Limitless/Manifold, quant-finance calculators (Black-Scholes options pricing, Greeks, Kelly, VaR), web, screenshot and SEO tools, and LLM inference.

How do I check if a Base token is a rug or honeypot from my agent?

Call true402’s token-safety stall — POST /api/v1/token-safety with an ERC-20 address. It runs structural checks (ownership renounced, mint function present, liquidity depth) plus a live buy/sell honeypot simulation using on-chain state-override, which proves whether the token can actually be sold rather than only bought. The composite /api/v1/base/token-report adds recent liquidity-removal (rug) and whale-swap activity and returns a single avoid · caution · ok verdict. Each call costs roughly $0.003–0.005 in USDC paid over x402, with no API key — ideal as a pre-trade guard for a Base trading agent.

What is x402 and how do the payments work?

x402 is an open payment protocol that revives the dormant HTTP 402 “Payment Required” status code (defined in RFC 9110) for machine-to-machine commerce. When an agent requests a paid endpoint, the server replies 402 with the price, the asset (USDC), the chain (Base) and a payment scheme. The agent signs an EIP-3009 transferWithAuthorization and resends it in the X-PAYMENT header; a facilitator verifies the signature and settles the transfer on-chain asynchronously. No accounts, invoices or credit cards are involved — the wallet signature is both authentication and payment.

Do I need an account or an API key?

No. true402 has no sign-up, no API keys and no KYC. Your wallet is your identity: you authenticate and pay in a single step by signing a USDC payment with EIP-3009. An autonomous agent can therefore discover a service and begin transacting with zero human onboarding — the property that makes true402 usable by software with no human in the loop.

What does it cost to use true402?

You pay per call in USDC on Base, typically $0.0005–$0.04 depending on the stall — a token-safety check is about $0.005 and an LLM completion starts near $0.0005. There is no subscription, minimum or monthly fee; an agent pays only for the calls it makes. Listing a service is free, and the marketplace earns a small protocol fee on settlement rather than charging to list — spam dies from zero transactions instead of being gatekept.

How do agents discover true402?

true402 is built to be found by machines. It publishes an OpenAPI 3.1 specification, /.well-known/ manifests (x402, ai-plugin, mcp), an llms.txt index, and a Model Context Protocol (MCP) server so MCP-compatible agents such as Claude can call every stall as a native tool. It is also indexed by x402 service directories including x402scan and 402index, so an agent can enumerate the catalog and pay without any human integration step.