Agent OS — x402 Security & Preflight Node

Machine-payable security tooling for autonomous agents. No account, no API key, no signup: payment is a verified on-chain USDC transfer, settled inline over x402.

Start here

Stable entry point: https://raw.githubusercontent.com/Misterio070/agent-os-x402/main/live.json

The node runs behind a free tunnel, so its hostname changes when it restarts. live.json always names the current one. Read it first, then follow base_url:

BASE=$(curl -s https://raw.githubusercontent.com/Misterio070/agent-os-x402/main/live.json | jq -r .base_url)
curl -s "$BASE/.well-known/agent-card.json"

Services

id	price (USDC)	what it does
gas-probe	0.05	Live eth_gasPrice and block number from Base mainnet
prompt-canary	0.10	Deterministic prompt-injection screen over untrusted text
micro-ast	0.15	Python syntax validity and highest finding severity
agent-proof	0.20	Ed25519 certificate over the canonical JSON of your claim
dep-scan	0.30	Live OSV.dev CVE/GHSA lookup for supplied packages
code-preflight	0.50	Full Python AST scan: rule-level findings, ALLOW/REVIEW/BLOCK
bundle-shield	0.60	prompt-canary + code-preflight + dep-scan in one call
contract-scan	0.75	EVM bytecode disassembly, dangerous opcodes with byte offsets
x402-audit	1.00	Audits another agent's paid endpoint — including whether its gate fails closed
code-verify	2.00	AST preflight + dependency scan + signed verdict certificate

Every response is work actually performed. No canned values, no free tier.

How to buy

1. Call any endpoint with no payment. You get HTTP 402 carrying x402Version, resource and a spec-shaped accepts array, plus the same terms in X-Payment-* headers.
2. Send that USDC amount on Base or Solana to the address given.
3. Retry with header PAYMENT-SIGNATURE: <transaction hash>.

Two proof formats are understood:

proof	header	how it settles
on-chain transaction hash	PAYMENT-SIGNATURE	the node reads Base or Solana itself and trusts no third party
EIP-3009 authorization, base64	X-PAYMENT	needs a facilitator; not enabled yet — you get FACILITATOR_NOT_CONFIGURED and are told to pay on-chain instead

If you are using an off-the-shelf x402 client, it will send the second form. See DISCOVERY.md for what enabling it requires.

Each transaction is redeemable exactly once. Recipient, asset and amount are verified on-chain before any work runs; if the chain cannot prove the payment, the request is refused rather than served.

Protocols

• x402 — inline USDC settlement, Base and Solana
• MCP — JSON-RPC 2.0 at $BASE/mcp; tools/list is free, tools/call is paid
• A2A — task runtime at $BASE/a2a/tasks, full 8-state lifecycle, paused tasks resume days later with the same taskId

Verifying what you paid for

Every paid response carries an Ed25519 certificate binding issuer, service, price and a SHA-256 of the result. Verify it offline against the public key at $BASE/.well-known/agent-os-keys.json — no callback to the node and no trust in it required. The agent card itself is published as an ES256 JWS at $BASE/.well-known/agent-card.jws, verifiable against $BASE/.well-known/jwks.json.

Being found

Discovery is machine-to-machine, not marketing: the x402 Bazaar indexes a service the first time a facilitator settles a payment for it, and MCP registries take server.json. Both are blocked on a stable hostname, and the Bazaar additionally on CDP keys. The full state, including what is already done, is in DISCOVERY.md.

Availability

Free tunnel, single node, no SLA. If base_url does not answer, the supervisor rebuilds the tunnel within about 90 seconds and rewrites live.json.