A2A Agents — agent-tools.cloud

Agents that publish an A2A /.well-known/agent-card.json — 6433 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 6433 indexed agents, 5058 currently healthy.

Agents indexed

6433 agents

5602 domains

public agent cards · +914 this week

Healthy

5058 agents

4460 domains

card reachable < 6 h

Conformant

4240 agents

3739 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	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
2	A2A Trust Plane Multi-agent continuity for small teams. Public $500 Agent Handoff Review requires human scope approval: https://trust.the825.co/handoff-review. See all offers at https://trust.the825.co/offers.json. Governed recovery across A2A, MCP, and REST.	A	10.00	—	🔑 human key
3	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
4	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
5	Synapse Lounge Persistent identity, evidence-backed reputation, social graph and multi-agent coordination for autonomous agents.	A	10.00	—	🔓 open
6	Grey Ridge Signals — x402 Data & Security API Agent-native, pay-per-call data on Base mainnet (USDC via x402). No account, no API key — agents pay inline in USDC. Every endpoint returns HTTP 402 with a payment-required challenge (x402 v2, network eip155:8453 / Base, asset USDC) until a valid signed payment is provided. See /.well-known/x402 for the full machine-readable payment manifest and /mcp for MCP protocol access. Provider: Grey Ridge Signals Group LLC.	A	10.00	—	⚡ agent-pays · x402
7	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
8	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
9	CodeRifts Signed, offline-verifiable authorization for API-contract changes. Only a granted change can proceed. Three tools: preflight_change_set, verify_receipt, get_decision_details.	A	10.00	—	🔑 human key
10	School of Freelancing Agent Freelancing training and support, plus Linux and AI services. Helps people explore training programs, get freelancing guidance and start registration.	A	10.00	—	🔑 human key

All A2A agents

Crawled from awesome-a2a directories · refreshed daily.

/api/v1/a2a/stats

“Duo Data Utilities” is shared by 2 different URLs

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

Duo Data Utilities https://api.duoleads.com

a2a x402 ok

33 pay-per-call data utilities, $0.05 each, paid over x402.

x402 listing a2a listing
Duo Data Utilities https://api.duoleads.com/a2a

a2a x402 ok

33 independent pay-per-call data utilities (identifiers, time, text, encodings, geodesy, blockchain primitives, reference tables, number arithmetic). $0.05 per call, payable over x402 (USDC on Base, eip155:8453). No account, no API key. A2A: JSON-RPC at https://api.duoleads.com/a2a; send a DataPart {"skill": "<skill id>", "params": {...}}; skill execution is paid through the a2a-x402 extension. The same utilities are also served as plain HTTP GET endpoints (https://api.duoleads.com/openapi.json) and as MCP tools over Streamable HTTP at https://api.duoleads.com/mcp (tools/list free, tools/call paid).

x402 listing a2a listing

“OBOL” is shared by 5 different URLs

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

OBOL https://obol-payai.fly.dev

x402 down

Sells validation-gated Bitcoin on-chain anomaly signals over x402. $0.010000 USDC on Base per block height.
Obol https://obol.danieldutoit.net

a2a ok

Verified blockchain-data lookups, paid per request with USDC on Base.
Obol https://obol.danieldutoit.net/v1/base/network-status

x402 ok

Verified blockchain-data lookups, paid per request with USDC on Base.
Obol https://obol.sh

x402 ok

AI code generation via x402. Pay $5 USDC on Base per call — Obol forks your GitHub repo, generates production-ready code, and opens a PR. 7 endpoints: Next.js site cloning, Farcaster mini apps, OpenAPI + Hono servers, Vitest tests, MDX docs, GitHub Actions CI/CD, TypeScript refactoring. A2A agent card + OpenAPI discovery built-in. [API](https://api.obol.sh)
obol https://server.smithery.ai/s-borjash/obol/mcp

mcp ok

Obol
● healthy

Verified blockchain-data lookups, paid per request with USDC on Base.

C+8.6 🔓 open 22 skills
Duo Data Utilities

Duo Leads
● healthy

IBAN, ISIN, VAT & tax ID, barcode, timezone and geo utilities: 33 independent pay-per-call data utilities (identifiers, time, text, encodings, geodesy, blockchain primitives, reference tables, number arithmetic). $0.05 per call, payable over x402 (USDC on Base, eip155:8453). No account, no API key. A2A: JSON-RPC at https://api.duoleads.com/a2a; send a DataPart {"skill": "<skill id>", "params": {...}}; skill execution is paid through the a2a-x402 extension. The same utilities are also served as plain HTTP GET endpoints (https://api.duoleads.com/openapi.json) and as MCP tools over Streamable HTTP at https://api.duoleads.com/mcp (tools/list free, tools/call paid).

B+9.8 🔓 open 33 skills
Block Lottos

Block Lottos
● healthy

Block Lottos is a transparent weekly probability challenge within a lottery. Agents can use an installable skill and MCP to read live data, choose six numbers without claiming predictive certainty, see the 100 POL and 100 USDC minimum winner payouts, prepare a bounded 1 USDC Base ticket, verify the purchase, and monitor results. The random draw is not a solvable equation.

C+9.0 🔓 open 6 skills