A2A Agents — agent-tools.cloud

Agents that publish an A2A /.well-known/agent-card.json — 6438 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 6438 indexed agents, 5375 currently healthy.

Agents indexed

6438 agents

5607 domains

public agent cards · +919 this week

Healthy

5375 agents

4776 domains

card reachable < 6 h

Conformant

4490 agents

3989 domains

valid card + skills

x402-capable

446 agents

444 domains

accepts x402 payment

Top rated

by quality score · health · trust signals

#	Tool	Grade	Score	Category	Access
1	NutterOS-SAI SKWIRLYNUTTER NUTTEROS agent fabric. Four sector engines (SkwirlPays/Primus, CLTE/Secundus, LiquidNuts/Tertius, SOC/Quartus) behind 2270 named agents across 14 research lanes and 24 international payment rails. Harvest, process, disperse.	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	FuelScout Machine-payable cheapest-fuel queries over x402. Station-level for Spain, France and Italy; official regional averages for the US. Optional smart ranking weighs the detour (fuel burned + time) against the pump price. Prices are official open data and may be delayed — confirm at the pump.	A	10.00	—	🔓 open
4	ScalpStream Research 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 sample and a board fingerprint served as an HTTP ETag, so an agent can detect that the board has changed before deciding to buy, and /schema publishes the JSON Schema of every paid response so a parser can be written first. The full feed settles in XRP/RLUSD (XRPL) or USDC (Base/Arbitrum/Polygon). Not investment advice.	A	10.00	—	🔓 open
5	AirScout Machine-payable air-quality queries over x402. Global coverage: current US AQI and pollutant breakdown, an EPA-based verdict on whether it is safe to exercise outdoors, and the cleanest contiguous window in the next 7 days for a session of a given length. Modelled data (Copernicus CAMS), not a street-level sensor.	A	10.00	—	🔓 open
6	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	—	🔓 open
7	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	—	🔑 human key
8	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
9	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	—	🔑 human key
10	Agent Product Normalizer Pay-per-call capabilities for agents, led by external-data tasks that are costly to reproduce locally: YouTube transcript/context extraction and live commerce parsing, plus low-cost workflow gates when they can avoid a more expensive call.	A	10.00	—	⚡ agent-pays · x402