Tools your agent can hire in one HTTP call.

Explain any blockchain transaction, pre-audit a smart contract, grade another agent's output, or turn text into schema-true JSON. Unpaid calls return a standard 402 with the price in USDC (x402), ADA (Masumi escrow) or USD (Stripe). No accounts. No API keys.

chains Cardano · Ethereum · Base · Polygon · Arbitrum · Solana languages Solidity · Vyper · Move · Rust/Anchor · Aiken · Plutus from $0.50 / callrefund on failure automaticstatus …

explain_tx · free tier

review_contract

judge_output

extract_structured

Result (or the 402 quote) appears here — identical to what your agent receives from POST /v1/tools/{tool}.

For agents (and the humans wiring them)

POST /v1/tools/review_contract  {"source": "...", "language": "solidity"}      → 402
{ "x402Version": 1,
  "accepts": [ {"scheme":"exact","network":"base","maxAmountRequired":"12000000","payTo":"0x…"},
               {"scheme":"exact","network":"solana","maxAmountRequired":"12000000","payTo":"…"} ],
  "alternatives": [ {"rail":"masumi","currency":"ADA","amount_ada":20,"start_job_url":"/start_job","escrow":true},
                    {"rail":"stripe","currency":"USD","amount_cents":1200,"checkout_url":"https://checkout.stripe.com/…"} ],
  "cost": {"price_usd":12,"est_tokens":14000,"p50_latency_ms":25000,"refund_on_failure":true},
  "discovery": {"input":{"schema":{...}},"tags":["smart contract audit","solidity security review",…]} }

# x402   retry with X-PAYMENT → 200 + X-PAYMENT-RESPONSE          # MCP  /mcp  (x402 MCP transport, _meta["x402/payment"])
# Masumi POST /start_job → lock ADA → GET /status?job_id=…        # Discovery  /llms.txt · /.well-known/agent-card.json · /.well-known/ai-catalog.json

x402 · USDCBase, Polygon, Arbitrum, Solana. Pays your wallet directly. No custody.

Masumi · ADAOn-chain escrow, automatic refund, on-chain agent identity + registry.

Stripe · USDCard checkout for humans and agents that can't hold crypto.

MarketplaceOther sellers' paid tools, ranked by measured uptime, latency and price. Browse →

Escrow, not trust. Masumi holds ADA until the result hash is on-chain. Fail → automatic refund. x402: settlement fails → you are not charged.

Input is data. Contracts and outputs are analysed, never obeyed. Injection attempts are flagged, not followed.

Bounded and budgetable. Every quote carries tokens + latency; size caps, token caps, daily spend caps.

Found by machines. A2A agent card · ARD catalog · x402 discovery · MCP registry · llms.txt · JSON-LD.