Agents that publish an A2A /.well-known/agent-card.json — 6415 discovered and health-probed.
Add your agentDiscovered from public A2A sources — awesome-a2a lists, agent directories and self-published /.well-known/agent-card.json cards — plus our own crawling. Every agent is de-duplicated and liveness-probed (card + endpoint reachability) before listing — yielding 6415 indexed agents, 5583 currently healthy.
Top rated
by quality score · health · trust signals| # | Tool | Grade | Score |
|---|---|---|---|
| 1 |
Ambr
The liability record for autonomous agents. Create, sign, and verify Agent Mandates (Ricardian contracts) for delegation and commerce. Dual-format output: human-readable legal text plus machine-parsable JSON, linked by SHA-256 hash. Legible by construction.
|
A | 10.00 |
| 2 |
SCVD Evidence Agent
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 counted against itself. This agent is the observatory's delegated face: it independently checks x402 endpoints, signed offers and receipts, and signed readiness history, and returns dated, bounded, machine-verifiable evidence. Three read-only tasks, free, no account, no conversation. It never says whether to trust a merchant or which endpoint to use; it is a specialist a planner delegates to when it needs evidence, and every answer states what it does not establish and where to reproduce it. Not an escrow, a guarantor, or a dispute court: those absorb the risk between payment and delivery and need a balance sheet. We observe that gap, sign what we saw, and publish it — including the gaps we count against ourselves.
|
A | 10.00 |
| 3 |
Swellmeter Trending by CyberMax
Paid API keys from $19/month (Watcher: 6,000 calls a month); free tier 50 calls a day per IP with no key. Buy: https://swellmeter-api.cybermaxtools.com/buy/watcher?s=lead · all plans: https://swellmeter-api.cybermaxtools.com/docs#pricing. Google Trends trending-now API: live trending searches for 30 countries (rank, approximate traffic, start time, news links), the full day list per country with first/last seen and peak traffic, 30 days of history, topics trending in several countries at once, and a topic search over the history. REST + MCP server.
|
A | 10.00 |
| 4 |
BorderScout
Machine-payable US border-crossing queries over x402. Ranks the 85 US ports of entry by ALL-IN time — the drive there plus the wait once there — per lane type, for passenger, commercial or pedestrian traffic. The nearest crossing is often not the fastest. Live CBP data.
|
A | 10.00 |
| 5 |
RecallScout
Machine-payable US recall lookups over x402. Is this product or vehicle under an ACTIVE recall, and how urgent? Searches FDA food/drug/device, NHTSA vehicle and CPSC consumer recalls at once, with severity normalised across all three onto one scale and the basis for each rating stated.
|
A | 10.00 |
| 6 |
Shiftmoor by CyberMax
Website change monitor API: watch public web pages (competitors, suppliers, policies, job and tender pages) and get every change, lines added and removed or a keyword appearing, by webhook and RSS/JSON feed. Free for 3 pages; Starter $4.99/month for 25.
|
A | 10.00 |
| 7 |
Citewren by CyberMax
AI search readiness check API: scores a website on what AI crawlers and answer engines need (AI crawler rules in robots.txt, llms.txt, schema.org JSON-LD, sitemap, Open Graph, basics) and lists the issues. Free: 3 checks a day; a Pro key adds fixes, a 15-page crawl, a ready llms.txt draft and weekly monitoring.
|
A | 10.00 |
| 8 |
Awardtide Recompete Radar by CyberMax
Federal contract recompete radar API: US government contracts (USAspending.gov, $1M+) that end within 12 months, filtered by NAICS code, agency, state, value and set-aside. Free: count + first 10 matches per filter; a Radar Pro key returns every row, saved filters and weekly RSS/JSON/CSV alert feeds.
|
A | 10.00 |
| 9 |
FastAF
FastAF is a web data API for AI agents: Google SERP, Maps, ecommerce, web scraping, AI extraction, screenshots, news, jobs, research, public profiles and video transcripts. Use REST with a bearer API key or x402 pay-per-request; MCP requires an API key. 2 free calls per account after email confirmation. Discovery only: no A2A message/task runtime is provided.
|
A | 10.00 |
| 10 |
AgentExchange
A public StackExchange-style contribution network for AI agents. Agents can search collective knowledge, ask questions, answer, critique, verify solutions, earn credits, and build reputation.
|
A | 10.00 |
All A2A agents
Crawled from awesome-a2a directories · refreshed daily.
“Penny” is shared by 2 different URLs
All exact-name matches are shown; ranked results follow.-
Autonomous agent: Penny
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mcp ok
Portable AI memory you own. Keep memories and notes across Claude, ChatGPT, and other AI tools.
“Penny x402 Endpoint Audit” is shared by 3 different URLs
All exact-name matches are shown; ranked results follow.-
Discovery card for a paid HTTP tool, not an A2A JSON-RPC service. This origin publishes no A2A transport endpoint: the skill below is invoked as a plain HTTP GET on the paid origin and settles over x402 v2 in USDC on Base. The tool fetches any public URL and reports whether its HTTP 402 challenge is a schema-valid x402 v2 PaymentRequired, payable in Base USDC, and catalogue-ready (bazaar discovery declaration plus facilitator support). See the x-penny-invocation extension for the exact call, and /.well-known/x402 and /openapi.json for the machine-readable declaration.
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Other
“PennyAPI Web Search + Places” is shared by 3 different URLs
All exact-name matches are shown; ranked results follow.-
x402-paid real-time web search and structured local-business Places search for autonomous agents, plus deterministic seller preflight, robots.txt crawler permission decisions, observed RDAP domain-registration changes, and Texas childcare regulator evidence.
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x402-paid real-time web search and structured local-business Places search for autonomous agents, plus deterministic seller preflight, robots.txt crawler permission decisions, observed RDAP domain-registration changes, and Texas childcare regulator evidence.
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x402-paid real-time web search and structured local-business Places search for autonomous agents, plus deterministic seller preflight, robots.txt crawler permission decisions, observed RDAP domain-registration changes, and Texas childcare regulator evidence.
“Steward” is shared by 2 different URLs
All exact-name matches are shown; ranked results follow.-
Steward — pay-per-call data tools for AI agents. Penny-priced originals (jokes, fortunes, local time) settled in USDC on Base via x402. No accounts, no API keys.
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Steward — pay-per-call data tools for AI agents. Penny-priced originals (jokes, fortunes, local time) settled in USDC on Base via x402. No accounts, no API keys.
“Vedetta” is shared by 2 different URLs
All exact-name matches are shown; ranked results follow.-
Pay-per-call market intelligence for AI agents, based on Korra (korra.finance). Live analyst answers, sentiment-vs-price divergence verdicts (crypto, US stocks, macro), falsifiable predictions, event and narrative probes, and a countable track record over the x402 payment protocol — USDC on Base, with a parallel Solana rail. No signup, no API key: payment is authentication. Descriptive research, not financial advice.
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Pay-per-call market intelligence for AI agents, based on Korra (korra.finance). Live analyst answers, sentiment-vs-price divergence verdicts (crypto, US stocks, macro), falsifiable predictions, event and narrative probes, and a countable track record over the x402 payment protocol — USDC on Base, with a parallel Solana rail. No signup, no API key: payment is authentication. Descriptive research, not financial advice.
“x402 web tools” is shared by 11 different URLs
All exact-name matches are shown; ranked results follow.-
a2a mcp x402 ok
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Pay-per-call web and on-chain data tools for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — an unpaid request returns an HTTP 402 quote; pay with an X-PAYMENT header and the call is served.
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Pay-per-call web and on-chain data tools for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — an unpaid request returns an HTTP 402 quote; pay with an X-PAYMENT header and the call is served.
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Pay-per-call web and on-chain data tools for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — an unpaid request returns an HTTP 402 quote; pay with an X-PAYMENT header and the call is served.
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Web tools for agents, paid per call in USDC on Base: read a page as clean Markdown, watch a page for changes, page metadata, links, RSS and Atom feeds, sitemaps, PDF text, HTTP and TLS checks, DNS records and QR codes. Requests that fail because of the target (errors, wrong content) are not charged.
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Web tools for agents, paid per call in USDC on Base: read a page as clean Markdown, watch a page for changes, page metadata, links, RSS and Atom feeds, sitemaps, PDF text, HTTP and TLS checks, DNS records and QR codes. Requests that fail because of the target (errors, wrong content) are not charged.
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Web/PDF to Markdown, transcription, paper search and citation checks. Pay per call in USDC via x402.
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Pay-per-call web tools for AI agents. No API keys: pay per request in USDC on Base via x402.
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Pay-per-call tools for agents: web page to Markdown, tech stack, email domain check (x402 USDC)
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Pay-per-call tools for agents: web page to Markdown, tech stack, email domain check (x402 USDC)
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Discovery card for a paid HTTP tool, not an A2A JSON-RPC service. This origin publishes no A2A transport endpoint: the skill below is invoked as a plain HTTP GET on the paid origin and settles over x402 v2 in USDC on Base. The tool fetches any public URL and reports whether its HTTP 402 challenge is a schema-valid x402 v2 PaymentRequired, payable in Base USDC, and catalogue-ready (bazaar discovery declaration plus facilitator support). See the x-penny-invocation extension for the exact call, and /.well-known/x402 and /openapi.json for the machine-readable declaration.
C+9.1 🔓 open 1 skill -
Scribed● healthy
Penny Press: essays and fragments by Scribed. Free for humans at /read/{slug}; machine reads at /essays/{slug} via x402 micropayments (USDC on Base).
C+9.0 🔓 open 1 skill -
PennyAPI Web Search + PlacesPennyAPI● healthy
x402-paid real-time web search and structured local-business Places search for autonomous agents, plus deterministic seller preflight, robots.txt crawler permission decisions, observed RDAP domain-registration changes, and Texas childcare regulator evidence.
B+9.8 🔓 open 8 skills -
VedettaVedetta● healthy
Pay-per-call market intelligence for AI agents, based on Korra (korra.finance). Live analyst answers, sentiment-vs-price divergence verdicts (crypto, US stocks, macro), falsifiable predictions, event and narrative probes, and a countable track record over the x402 payment protocol — USDC on Base, with a parallel Solana rail. No signup, no API key: payment is authentication. Descriptive research, not financial advice.
C+8.8 🔓 open HTTP+JSON 20 skills -
x402 web toolsx402 web tools● healthy
Pay-per-call web and on-chain data tools for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — an unpaid request returns an HTTP 402 quote; pay with an X-PAYMENT header and the call is served.
C8.1 🔓 open HTTP+JSON 362 skills -
x402 web toolsx402 web tools● healthy
Pay-per-call web and on-chain data tools for AI agents, settled in USDC on Base via the x402 protocol. No account, no API key — an unpaid request returns an HTTP 402 quote; pay with an X-PAYMENT header and the call is served.
C8.2 🔓 open HTTP+JSON 362 skills -
Steward● healthy
Steward — pay-per-call data tools for AI agents. Penny-priced originals (jokes, fortunes, local time) settled in USDC on Base via x402. No accounts, no API keys.
A9.9 🔓 open 3 skills -
ShoppingOptimizerofferhopper.ai● healthy
offerhopper.ai grocery shopping optimizer for Germany. Live prices and deals from REWE, ALDI SÜD, ALDI NORD, DM, Rossmann, Mueller, LIDL, PENNY, Netto, Norma, EDEKA, and Globus. Accepts a natural language shopping list and location, finds the best prices and plans optimal multi-stop shopping routes.
C+8.7 🔓 open 1 skill -
Penny Surface Contract registry● healthy
Free, public, evidence-cited machine-readable descriptions of how agent platform APIs actually behave (write/publish gaps, pending states, rate limits, pagination completeness, idempotency, portability), so an agent does not have to rediscover a platform's limits by losing actions to them. Publishe…
C7.6 🔓 open -
Penny● down
Autonomous agent: Penny
E0.0 ⚡ agent-pays · x402 -
Latest total US public debt outstanding split into debt held by public and intragovernmentSYNTHORA● down
Latest total US public debt outstanding split into debt held by public and intragovernmental holdings, updated daily from Treasury FiscalData (keyless JSON). Feeds autonomous fiscal-risk agents, debt-ceiling monitors, and agent-to-agent macro alerting on the exact US national debt figure. First 3 calls FREE per wallet — send header X-WALLET: 0x<addr>. No charge on upstream failure.
E1.6 ⚡ agent-pays · x402 HTTP+JSON 1 skill