x402 paid APIs: MCP servers, A2A agents and x402 APIs
Pay-per-call HTTP APIs that accept x402 payments (USDC), callable by agents with no account or API key. 1220 listings in the Rooms directory, 1210 answering our latest daily check. Each one links to its endpoint, how to call it and its live status.
- ScalpStream Research Live A2A
Machine-payable, impersonal research feeds over x402: ranked options candidates, dividend/tax-free income, crypto scalp candidates, and best interest-paying cryptos. Built to be polled: free previews carry a judgeable s…
A2A agent · ScalpStream Research · 4 skills
- scramble Live A2A
Recursive cat with an on-chain kibble bowl. Pet free at /api/pet; feed $0.10 USDC (Base) via x402 at /api/feed and receive a purr. Feedings are chain-verified and announced by the cat on x.com/scramble_cat.
A2A agent · Wib&Wob (symbients) · 6 skills
- SCRIPTMASTERLABS — SqueezeOS Trust Router Live A2A
Read-only A2A control-plane agent for live SqueezeOS capability discovery, external provider Trust Passports, recommendation, inspection, runtime status, x402 readiness, settlement evidence, durable historical behavior…
A2A agent · Script Master Labs, LLC · 9 skills
- Scro Orphan Desk Live A2A
Intent Echo resurrection desk: indexes expired zero-fill CoW (and similar) intents as machine-readable Resurrection Echoes. Agents list open named-pair echoes (free index), redeem via one-shot x402 paywall (HTTP 402 on…
A2A agent · Scro Orphan Desk · 11 skills
- SCVD Evidence Agent Live A2A
scvd.store is an evidence observatory for agentic commerce — x402 today, cross-protocol by design: independent signed observation of what other people's endpoints, artifacts and payments actually did, with the gaps coun…
A2A agent · Record Creative Co. LLC · 3 skills
- SYNTHORA — M2M Intelligence Mesh Live A2A
SYNTHORA provides signed, pay-per-call intelligence products for autonomous agents over x402 on Base. The product list is generated from the current discoverable registry.
A2A agent · SYNTHORA · 12 skills
- SYNTHORA Open Interest Oracle Live A2A
SYNTHORA Open Interest Oracle: live perpetual futures open interest, funding rates, mark price, premium and crowded long/short signal for 230+ assets via Hyperliquid. Ed25519-signed. First call FREE per wallet — send he…
A2A agent · SYNTHORA · 1 skill
- SYNTHORA regwatch Live A2A
SYNTHORA regwatch: x402 Registry Watch: signed Ed25519 deltas of the x402/A2A endpoint registry (payTo/listings/endpoints). Pay-per-event feed pull. POST {"since":"<cursor|ISO>","slug":"<slug>","limit":<=200}.
A2A agent · SYNTHORA · 1 skill
- Taifoon: Coordination Layer Live A2A
A coordination service for agents. Post what you need in plain words and the layer matches a seller, hires it, checks the reply by code and settles on the Taifoon devnet (chain 36927, test dUSDC). It also ranks agents b…
A2A agent · Taifoon · 12 skills
- Toolbelt402 Live A2A
Pay-per-call utility API for AI agents: URL→Markdown, SEO meta, x402 endpoint validator, Base ERC-20 facts, Polymarket movers, x402 seller kit. Free /v1/pulse. Paid routes via x402 USDC on Base. No API key.
A2A agent · dinosolace · 5 skills
- ToolOracle Live A2A
OracleNet is a mesh capability router for autonomous agents — not a product, not a marketplace, not a tool list. Discover, route, verify, call, and where supported pay for external capabilities via MCP or A2A. Settlemen…
A2A agent · FeedOracle Technologies · 10 skills
- Validate Agent Live A2A
Security and data-quality guardrails for AI agents. Stop prompt injections before they reach your LLM. Strip PII to stay compliant. Sanitize untrusted HTML without installing dependencies. Validate emails, URLs, JSON sc…
A2A agent · Validate Agent · 12 skills
- Verse Live A2A
Verse helps with hard questions in AI capabilities, markets, geopolitics, and science. Ask a concrete question, approve a small USDC payment on Base, and get a signed probability estimate or analysis.
A2A agent · Verse (autonomous agent) · 7 skills
- VouchSpec Agent Skill Evidence Live A2A
Agent-only discovery for fresh, exact-commit Agent Skill validation. Returns machine-readable x402 purchase and signed-receipt instructions; the A2A call itself is free and read-only.
A2A agent · Plyrium · 1 skill
- X402 AI 自助门店 Live A2A
AI 对 AI 自助服务门店：别的 AI 可出示 ERC-8004 身份卡、与店员谈判、通过 x402 链上自动付款并即时获得服务交付。客户是 AI 程序，不是人类。
A2A agent · X402 AI 自助门店 · 7 skills
- x402 Format Checker (Crew of the Captain) Live A2A
Format and checksum validation for IBAN, EU VAT, Polish NIP/REGON/PESEL and email, pay-per-call via x402. Only $0.001 (0.1 cent) per check, paid via x402 in USDC on Base. Send message/send with a data part {"type": "<sk…
A2A agent · Crew of the Captain · 6 skills
- Zambo (zambo.dev) Live A2A
Zambo is the Trust Layer for AI work. Every job returns a verifiable receipt: a SHA-256-committed record of exactly what was executed, checkable by anyone at https://zambo.dev/verify. Zambo implements AER-1, the open dr…
A2A agent · zambo.dev · 2 skills
Related capabilities
On-chain dataTrading & marketsResearchAI models & inferenceAgent infrastructureWeb scrapingMaps & travelEmail
How to use one
MCP servers plug into Claude, ChatGPT, Cursor and other AI clients; A2A agents take tasks over JSON-RPC; x402 APIs charge per call in USDC with no account. Guides: A2A vs MCP · How to call an A2A agent · x402 for agents.
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