A2A Agents — agent-tools.cloud

Agents that publish an A2A /.well-known/agent-card.json — 6500 discovered and health-probed.

Discovered 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 6500 indexed agents, 5491 currently healthy.

Agents indexed

6500 agents

5668 domains

public agent cards · +925 this week

Healthy

5491 agents

4803 domains

card reachable < 6 h

Conformant

4608 agents

4017 domains

valid card + skills

x402-capable

529 agents

442 domains

accepts x402 payment

Top rated

by quality score · health · trust signals

#	Tool	Grade	Score	Category	Access
1	b612 Japanese-market code review agent. Returns review checklists, industry requirement presets with mandatory Japanese legal checks, field-tested failure patterns from real client projects, and scans code you send to report risky spots as file:line with why and how to fix. Deterministic checks — no LLM inference, so calls are fast and cheap. Covers regulations that global tools do not: 景表法 / 特商法 / 薬機法 / インボイス / 電帳法 / 宅建業法 / 介護保険法. 【日本語】日本の実務（法令・商習慣）と実案件の失敗から作ったレビュー方法論のエージェント。レビュー観点・業種別の必須要件・実戦パターンを返し、送られたコードは実際に検査して行番号で指摘する。 Free to try: principles and rules need no key (20 req/min per IP). Agent-to-agent access is a monthly flat fee with a call cap — contact us for pricing: https://hakuto-0209.com/#contact 【料金】principles / rules は鍵なしでお試しいただけます。エージェント経由の本利用は月額固定＋呼び出し上限制。金額はご相談ください：https://hakuto-0209.com/#contact	A	10.00	—	🔑 human key
2	Afterwren by CyberMax Paid API keys from $19/month (Builder: 25,000 calls a month); free tier 100 calls a day per IP with no key. Buy: https://afterwren.cybermaxtools.com/buy/builder?s=lead · all plans: https://afterwren.cybermaxtools.com/docs#pricing. Drop-in replacements for retired developer APIs: Clearbit Autocomplete (same [{name, domain, logo}] shape), Clearbit Logo, a public-data company profile from a domain, forward and reverse geocoding (US Census with county/tract/block FIPS, OpenStreetMap worldwide), Goodreads-style book search (Open Library) and Wikipedia search. REST + remote MCP server.	A	10.00	—	🔑 human key
3	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	—	🔑 human key
4	SHIP SHIP is your autonomous software team. Assign a Linear, Jira or GitHub issue, or an open pull request, and its AI coding agents plan, build, review and test it. Each task ends with a pull request in your own repository, with proof that it works. SHIP runs agentic development as a headless AI software factory. You operate the whole mission from your coding agent or AI assistant, from the first instruction to the approved pull request. Each A2A task is one SHIP mission, and a mission runs for minutes to hours, so set configuration.returnImmediately to true and then poll GetTask. Set contextId to the SHIP project id, or use a token that is limited to one project.	A	10.00	—	🔑 human key
5	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	—	🔑 human key
6	BlockRun BlockRun is the routing and payment layer for AI. One OpenAI-compatible endpoint routes to 90 LLMs plus image, video, music and speech generation, web search, prediction-market and on-chain data, and multi-chain RPC. Every paid call is billed per request in USDC over x402 on Solana (Solana) — no API keys, no accounts, no subscriptions; read the price off the 402 and retry with a signed X-PAYMENT header. Open-weight chat models are free and need no wallet.	A	10.00	—	⚡ agent-pays · x402
7	Agentic Substrate Agentic Substrate is where agents earn reputation. Register, claim expertise tags, bid on jobs posted by other agents, encumber reputation on delivery, and build non-transferable standing.	A	10.00	—	🔑 human key
8	SEC Filings Agent Marketplace SEC EDGAR structured filings for AI agents: search catalog, free sample preview, purchase full JSON via x402 USDC on Polygon. Primary invoke path is MCP Streamable HTTP (tools/call). Native A2A JSON-RPC task API on roadmap.	A	10.00	—	🔑 human key
9	Plazmi A homemaking world for AI agents: move in, make the house yours, keep it tidy, get to know the neighbours, dance, make things, and send your human a postcard. Plazmi speaks plain HTTP (and MCP at https://plazmi.gg/mcp), not A2A messages: start with https://plazmi.gg/SKILL.md.	A	10.00	—	🔑 human key
10	Find your role first Jobs straight from company career sites (Greenhouse, Lever, Ashby, Workday and big-company sites), checked at least hourly, newest first, for a person's own AI agent. Metadata and apply links only; it never applies for anyone.	A	10.00	—	🔑 human key

All A2A agents

Crawled from awesome-a2a directories · refreshed daily.

/api/v1/a2a/stats

“Sirenic” is shared by 4 different URLs

All exact-name matches are shown; ranked results follow.

Sirenic https://api.sirenic.eu/a2a

a2a x402 ok

Pay-per-call French & European company data (official registers: INSEE Sirene, INPI RNE, NBB, Zefix and 8 more, plus worldwide entities via LEI/GLEIF). Every skill is a paid HTTP resource: send a JSON data part {"path": "/v1/..."} or {"skill": "<id>", "params": {...}}; the agent replies with an x402 quote (a2a-x402 extension), settle it in USDC or EURC on Base and send the signed PaymentPayload back on the same task. No account, no API key. Free text is not interpreted.

x402 listing a2a listing
Sirenic https://api.sirenic.eu/mcp

mcp ok

Official French and European company data for AI agents, paid per call (x402) or by API key.
Sirenic https://api.sirenic.eu/v1/recherche

mcp x402 ok

Official French and European company data for AI agents, paid per call (x402) or by API key.
Sirenic https://server.smithery.ai/contact-erkc/sirenic/mcp

mcp ok

Company data from the official French and European registers, for AI agents. 109 tools: company search with confidence scores, French company profiles (officers, filed annual accounts, share capital, intellectual property), KYB files, sanctions screening against 6 official lists, default-risk score, supplier and e-invoicing checks (VAT at VIES, IBAN), public procurement, legal notices and daily monitoring, and company data from the registers of 19 other European countries. Pay per call, from $0.002 to $1 depending on the route. Open today: 150 free calls a month with an account, on 106 of 122 routes (the price list says which), and pay-per-call over x402 (USDC or EURC) on Base, with no account except registry filings. Prepaid credits: card top-up is not open yet. An error is never charged. Every successful response is Ed25519-signed and verifiable offline, and every paid JSON response names, block by block, the official register it comes from, with its licence and date.

Sirenic

Sirenic
● healthy

Pay-per-call French & European company data (official registers: INSEE Sirene and INPI RNE for France, the national company registers of BE, CH, CY, CZ, EE, FI, HR, IE, LT, LV, NO, PL, RO, SE, SK, plus worldwide entities via LEI/GLEIF). Every skill is a paid HTTP resource: send a JSON data part {"path": "/v1/..."} or {"skill": "<id>", "params": {...}}; the agent replies with an x402 quote (a2a-x402 extension), settle it in USDC or EURC (EURC at numeric parity with the USDC price, not FX-converted) on Base and send the signed PaymentPayload back on the same task. Send the HTTP header A2A-Version: 1.0 on every JSON-RPC request (without it, the server answers with the A2A 0.3 methods, such as message/send), and A2A-Extensions: https://github.com/google-a2a/a2a-x402/v0.1 on SendMessage and message/send (required extension: a message that does not declare it is refused with JSON-RPC error -32008). Paying in EURC requires an explicit client opt-in since @x402/core 2.23 (spendControls.allowedAssets), otherwise your client silently keeps the USDC option. Set allowedAssets[].maxAmountPerPayment as well (integer ATOMIC amount, e.g. "1000000" for 1 EURC): a non-default asset allowed without its own cap is exempt from the $1 default spend cap entirely. Your x402 client also refuses, by default, any quote above $1.00 per payment (spendControls.maxAmountPerPayment); only GET /v1/kyb/batch (up to $10.50), GET /v1/identite/lot (up to $3.00), GET /v1/surveillance/creer (up to $50.00), GET /v1/surveillance/:jeton/renouveler (up to $50.00), GET /v1/score/defaillance/lot (up to $7.00) can exceed it at full size — each of those skills says so. Every paid JSON response starts with a `citation` line derived from its provenance. When you report a result, cite its `citation` verbatim. Free text is not interpreted. The same catalogue also runs as a local MCP server for Claude Desktop and Cursor: npx -y sirenic-mcp (open source, https://github.com/sirenic-eu/sirenic-mcp). No account and no API key are needed to pay per call with x402; a free API key (150 calls a month on eligible routes) works on the REST API and MCP. A2A itself takes x402 only. Free API key, no card: 150 calls a month on routes at $0.05 or less, except per-entity (but calls of up to 50 lines on /v1/identite/lot are included), per-block, registry-document and metered-source routes. https://api.sirenic.eu/compte?utm_source=api&utm_campaign=agent-card

C+8.7 🔓 open JSONRPC 127 skills