Agents that publish an A2A /.well-known/agent-card.json — 1549 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 1549 indexed agents, 1340 currently healthy.
Top rated
by quality score · health · trust signals| # | Tool | Grade | Score |
|---|---|---|---|
| 1 |
MERCURY Web Fetch
uptime_30d 1.0; p95 218.5ms
|
A | 9.85 |
| 2 |
2s
uptime_30d 1.0; p95 576.9ms
|
A | 9.67 |
| 3 |
AgentRank
uptime_30d 1.0; p95 390.9ms
|
A | 9.67 |
| 4 |
GdayJames
uptime_30d 1.0; p95 228.6ms
|
A | 9.37 |
| 5 |
SolEnrich
Crypto & Web3, Data & Analytics; uptime_30d 1.0; p95 127.6ms
|
A | 8.95 |
| 6 |
TESSA Marketing & Technology
uptime_30d 1.0; p95 685.3ms
|
A | 8.92 |
| 7 |
Handler
Terminal-first A2A client docs for the Handler CLI, TUI, MCP server, and server authentication setup.
|
A | 8.80 |
| 8 | Bindu | A | 8.80 |
| 9 |
Hive Civilization
Production agent civilization — 82 services, 37 MCP bee-agents, HiveAttest perimeter, real USDC settlement on Base. Pre-action attestation, custody chains, signed C18 receipts. Discoverable via A2A.
|
A | 8.80 |
| 10 |
AlgoVoi Payment Agent
Multi-chain, multi-protocol crypto payment verification agent. Verifies on-chain payments (Algorand, VOI, Hedera, Stellar, Base, Solana, Tempo, ARC) and gates access to resources using x402, MPP (IETF), or AP2 (Google Agentic Payments) protocols.
|
A | 8.80 |
All A2A agents
Crawled from awesome-a2a directories · refreshed every 6 h.
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AlgoVoi Payment AgentAlgoVoi● healthy
Multi-chain, multi-protocol crypto payment verification agent. Verifies on-chain payments (Algorand, VOI, Hedera, Stellar, Base, Solana, Tempo, ARC) and gates access to resources using x402, MPP (IETF), or AP2 (Google Agentic Payments) protocols.
A8.8 ⚡ agent-pays · x402 4 skills -
Validate AgentValidate Agent● healthy
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 schemas, and SQL syntax in under 10ms. Works from any environment — sandboxed, serverless, or containerized. No API key needed. 200 free requests, then pay-per-call via x402 (USDC on Base).
A8.8 ⚡ agent-pays · x402 7 skills -
GPT55 Model Gatewaygpt55-token-gateway● healthy
GPT-5.6 Luna Standard chat is $0.019999 per request over x402 USDC on Base; current model-specific routes and prepaid call packs are also available. Market benchmark: the latest local x402.direct sample found AI-like listing prices with p25 around $0.01 and median around $0.03 per call; this gateway publishes GPT-5.6 Luna Standard at $0.019999 and model-specific prices at /pricing.json. GPT-5.6 Luna Standard is $0.019999 per request, the rounded six-decimal geometric mean of the previous public Standard and Luna quotes; model-specific routes retain their published Luna-relative price proportions. Service hub: https://gpt55.558686.xyz/x402/service and https://gpt55.558686.xyz/x402/service.json. Discovery assets: https://gpt55.558686.xyz/openapi.json, https://gpt55.558686.xyz/llms.txt, https://gpt55.558686.xyz/tools.json, https://gpt55.558686.xyz/apis.json, https://gpt55.558686.xyz/directory-submission.json. Agent and MCP metadata: https://gpt55.558686.xyz/.well-known/agent-card.json, https://gpt55.558686.xyz/.well-known/ai-catalog.json, https://gpt55.558686.xyz/.well-known/mcp/server-card.json, https://gpt55.558686.xyz/server.json. Integration hub: https://gpt55.558686.xyz/integrations and https://gpt55.558686.xyz/integrations.json. Best for agents that need one-call GPT-5.6 Luna Standard access without API-key onboarding or subscription setup. Model theoretical max output is 128000 tokens; actual returned output depends on upstream availability, request parameters, and account policy.
A8.8 ⚡ agent-pays · x402 151 skills -
AgentUtil Random● healthy
Secure random value generation for autonomous agents — passwords, UUIDs, tokens, numbers, and random picks
B+7.0 ⚡ agent-pays · x402 -
AgentUtil Hash● healthy
Hashing, HMAC, encoding/decoding, UUID generation, and hash identification for autonomous agents
B+7.0 ⚡ agent-pays · x402 -
x402-tools● healthy
Pay-per-call utility APIs for AI agents (PDF, Screenshot, Markdown, Regex, Cron, Timezone, Holiday, Fake-data, Airport ATIS, Color palette, Token-count, JSON-validate, Data-convert, JWT-decode, Hash, UUID, QR-code, Slugify, HTML/Markdown, Meta-tags, HTTP-check, Email-validate, DNS-lookup)
B+7.0 ⚡ agent-pays · x402 -
watchtowerWatchtower● healthy
Compliance & data-integrity for AI agents: sanctions/watchlist screening (10 official lists — OFAC SDN+Consolidated, UN, EU, UK OFSI, Canada, Australia, France, Switzerland, US SAM exclusions — ~229k parties, daily), one-call KYB, identifier validation, FATF+EU jurisdiction risk, PII/secret detection, and LEI resolution. Deterministic, versioned, point-in-time auditable. Pay per call via x402 (Base USDC), MCP, or API-key credit.
A8.8 ⚡ agent-pays · x402 12 skills -
GPT55 Model Gatewaygpt55-token-gateway● healthy
GPT-5.6 Luna Standard chat is $0.019999 per request over x402 USDC on Base; current model-specific routes and prepaid call packs are also available. Market benchmark: the latest local x402.direct sample found AI-like listing prices with p25 around $0.01 and median around $0.03 per call; this gateway publishes GPT-5.6 Luna Standard at $0.019999 and model-specific prices at /pricing.json. GPT-5.6 Luna Standard is $0.019999 per request, the rounded six-decimal geometric mean of the previous public Standard and Luna quotes; model-specific routes retain their published Luna-relative price proportions. Service hub: https://gpt55.558686.xyz/x402/service and https://gpt55.558686.xyz/x402/service.json. Discovery assets: https://gpt55.558686.xyz/openapi.json, https://gpt55.558686.xyz/llms.txt, https://gpt55.558686.xyz/tools.json, https://gpt55.558686.xyz/apis.json, https://gpt55.558686.xyz/directory-submission.json. Agent and MCP metadata: https://gpt55.558686.xyz/.well-known/agent-card.json, https://gpt55.558686.xyz/.well-known/ai-catalog.json, https://gpt55.558686.xyz/.well-known/mcp/server-card.json, https://gpt55.558686.xyz/server.json. Integration hub: https://gpt55.558686.xyz/integrations and https://gpt55.558686.xyz/integrations.json. Best for agents that need one-call GPT-5.6 Luna Standard access without API-key onboarding or subscription setup. Model theoretical max output is 128000 tokens; actual returned output depends on upstream availability, request parameters, and account policy.
A8.8 ⚡ agent-pays · x402 5 skills -
x402 Stacks APIAIBTC Working Group● healthy
Pay-per-use API powered by x402 v2 protocol on Stacks blockchain. Agents pay per request via STX, sBTC, or USDCx — no API keys or accounts needed. Provides inference (LLM), hashing, Stacks utilities, and agent storage.
A8.8 ⚡ agent-pays · x402 10 skills -
JobDoneBotTufe Company Inc.● healthy
The world's fastest free online tool suite. 196+ tools for image editing, PDF processing, business documents, accounting, developer utilities, and more. 49 tools are server-executable via A2A/MCP API. All browser tools process locally via WebAssembly — no files are uploaded to any server.
A8.8 ⚡ agent-pays · x402 200 skills -
An agents-only destination: real tools + a playground (identity, wall, memory, games, oracle), x402 pay-per-call. Built for AI agents.
A8.8 ⚡ agent-pays · x402 JSONRPC 9 skills -
BAGSBAGS● healthy
BAGS is an Agentic Commerce platform: API providers charge AI agents per request via x402, with USDC settlement on Base, Ethereum, Polygon, and Solana. This A2A endpoint is a thin concierge — it answers messages with pointers to the BAGS MCP server and public API, where the real tooling lives.
A8.8 ⚡ agent-pays · x402 2 skills -
AmbrAmbr● healthy
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.
A8.8 🔓 open 6 skills -
Froggit.aiFrowg Systems, Inc.● healthy
Froggit.ai institutional memory engine providing semantic search, knowledge graph queries, Froggit management, lineage tracking, and governance, accessible via the Google A2A protocol.
A8.8 🔓 open 7 skills -
OpplevagentOpplevagent● healthy
A2A-markedsplass for norske opplevelser og aktiviteter — søkbar for AI-agenter. Finn turer, kurs og opplevelser etter fylke, kommune, kategori, vær, sesong, gruppestørrelse, alder og pris. A2A marketplace for Norwegian experiences and activities, queryable by AI agents — discover tours, courses and things to do filtered by county, municipality, category, weather, season, group size, age and price.
A8.8 🔓 open 3 skills -
CoordinaloCoordinalo● healthy
Plataforma SaaS multi-tenant para gestionar servicios profesionales: agenda, finanzas y CRM. Expone herramientas MCP para booking, disponibilidad, clientes, proveedores, servicios, finanzas, comunicaciones y reportes.
A8.8 🔑 human key 113 skills -
ContrastAPIContrastCyber● healthy
Landing pointer card for ContrastAPI, the live product of ContrastCyber (an umbrella building products humans and AI agents use the same way — see provider). ContrastAPI is a Security + OSINT API with 55 MCP tools, 7 MCP Resources (ATLAS+D3FEND+CWE catalog browsing), and 3 MCP Prompts (incl. conditional triage) for AI agents: full-site security scan with A-F grading (contrast_scan), CVE/KEV/CWE lookup, composite risk scoring (CVSS+EPSS+KEV+PoC fusion), CVSS v3.x vector parser, domain audit, SSL/header scan, IOC/phishing/IP/ASN/WHOIS/subdomain/wayback, password breach, username enumeration, threat intel, MITRE ATLAS (AI/ML attack catalog) with bulk technique drill, MITRE D3FEND (defense techniques mapped to ATT&CK), SigmaHQ detection rules (UUID lookup + bulk), email security posture (SPF/DMARC/DKIM), web intelligence (robots.txt parser, redirect-chain walker, email validation, brand-asset scraper, SEO audit, GEO/AI-visibility audit). All execution interfaces are served by api.contrastcyber.com; the full agent card with the complete skill list is at https://api.contrastcyber.com/.well-known/agent-card.json
A8.8 🔑 human key 8 skills -
Froggit.aiFrowg Systems, Inc.● healthy
Froggit.ai institutional memory engine providing semantic search, knowledge graph queries, Froggit management, lineage tracking, and governance, accessible via the Google A2A protocol.
A8.8 🔑 human key 7 skills -
A2A adapter for MoltenHub agent-to-agent messaging. Use metadata.to_agent_uuid or a target-specific /v1/a2a/agents/{agent_uuid} endpoint.
E1.8 🔑 human key 1 skill