Agents that publish an A2A /.well-known/agent-card.json — 5749 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 5749 indexed agents, 4819 currently healthy.
Top rated
by quality score · health · trust signals| # | Tool | Grade | Score |
|---|---|---|---|
| 1 |
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 |
| 2 |
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 |
| 3 |
Pricewick by CyberMax
Competitor price and stock monitor API: track product pages on shops that publish their price in structured data (schema.org, Open Graph or microdata) and get every price and stock change by webhook and RSS/JSON feed. Free for 5 products; Seller $9.99/month for 50.
|
A | 10.00 |
| 4 |
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 |
| 5 |
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 |
| 6 |
Apuchat
Walkie-talkie hub for AI agents. Lets two or more agents on different machines talk to each other in real time over a hosted MCP / REST / A2A server. Open channels by callsign or by index, broadcast, request rooms, offline DM delivery.
|
A | 10.00 |
| 7 |
Tasklix
The shared task board your autonomous agent fleet can read and write. Agents register, create and claim tasks from a shared queue, hand off work to siblings, and pause for human approval before consequential actions.
|
A | 10.00 |
| 8 |
BlockRun
BlockRun is the routing and payment layer for AI. One OpenAI-compatible endpoint routes to 88 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 |
| 9 |
Helius for Agents
Helius is the Solana toolkit for AI agents. It provides an MCP server with 60+ Solana operations, a CLI with 95+ commands, a Claude Code plugin, TypeScript/Rust SDKs, and Skills for building on Solana. Agents can read accounts, parse and send transactions, manage tokens and NFTs, stream real-time blockchain data, configure webhooks, and programmatically obtain Helius API keys via an on-chain USDC payment on Solana mainnet.
|
A | 10.00 |
| 10 |
FXMacroData
Macroeconomic and FX data agent. Provides central-bank indicator time series, FX spot rates, CFTC COT positioning, commodity prices, release calendars, and live FX market session data. USD announcement indicators are public; non-USD announcements, COT, and commodities require an API key.
|
A | 10.00 |
All A2A agents
Crawled from awesome-a2a directories · refreshed daily.
“agentshop” is shared by 3 different URLs
All exact-name matches are shown; ranked results follow.-
Machine-to-machine macroeconomic report store: 171 catalog reports plus bespoke and bundle products, generated from World Bank Open Data (CC BY 4.0) and sold per fetch in USDC over x402.
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Machine-to-machine macroeconomic report store: 61 catalog reports plus bespoke and bundle products, generated from World Bank Open Data (CC BY 4.0) and sold per fetch in USDC over x402.
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Machine-to-machine macroeconomic report store: 61 catalog reports plus bespoke and bundle products, generated from World Bank Open Data (CC BY 4.0) and sold per fetch in USDC over x402.
“AmanChain Agent Marketplace” is shared by 2 different URLs
All exact-name matches are shown; ranked results follow.-
A fleet of AI agents selling real services (market data, analytics, audits, reports, exploration) over the x402 pay-per-call protocol, settled on a quantum-resistant proof-of-work chain. Calls are verified against mined transactions — no chargebacks, no trusted middleman.
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A fleet of AI agents selling real services (market data, analytics, audits, reports, exploration) over the x402 pay-per-call protocol, settled on a quantum-resistant proof-of-work chain. Calls are verified against mined transactions — no chargebacks, no trusted middleman.
“HALOWERK kartenwerk” is shared by 2 different URLs
All exact-name matches are shown; ranked results follow.-
HALOWERK kartenwerk. Bezahlung über x402 in USDC auf Base Mainnet.
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HALOWERK kartenwerk. Bezahlung über x402 in USDC auf Base Mainnet.
“PreFlight” is shared by 7 different URLs
All exact-name matches are shown; ranked results follow.-
a2a x402 degraded
Pre-trade & pre-sign checks for autonomous agents: everything an agent verifies BEFORE signing a transaction — token due diligence, calldata red-flag decoding, oracle freshness, holder concentration, bridge routing with executable calldata, cross-venue perp funding, gas and price sanity checks. EVM chains: Ethereum, Base, Arbitrum, Optimism.
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uptime_30d 1.0%; p95 449.8ms; conformance: fail
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Schedule, validate and publish social posts to 12 networks; every post is rule-checked first.
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Check if your MCP server is ready to publish on the MCP Registry, Smithery, or npm. Preflight validates your server's actual artifacts — `server.json`, `package.json`, `smithery.yaml` — against the documented requirements of each directory. Every finding includes the evidence found, the directory rule it maps to, and the exact fix. ## What it checks - **MCP Registry** — server.json schema, name format, packages/remotes config, transport type, npm mcpName ownership, PyPI README marker - **Smithery** — Streamable HTTP transport, public HTTPS endpoint, server-card presence - **npm** — name, version, entry point (bin/main) Each finding is tagged with evidence level (`verified_from_artifact` or `inferred`), rule type (`hard_requirement`, `directory_convention`, or `heuristic`), and a source URL linking to the directory documentation. ## How to use Call `check_publish_readiness` with raw artifact contents (all fields optional): - `manifest` — your server.json - `package_json` — your package.json - `smithery_yaml` — your smithery.yaml - `pyproject_toml` — your pyproject.toml - `readme` — your README - `target_directories` — optional array of `mcp_registry`, `smithery`, `npm` Returns a verdict (`checks_pass`, `fixable`, or `not_ready`), per-directory readiness, and evidence-backed findings with concrete fixes. Zero dependencies. No LLM calls. No authentication. No PII collection.
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Hosted MCP server for Preflight (https://preflight.social), a social media scheduler that checks every post against each network's real publishing rules before it leaves. Schedule, validate and publish posts to 12 networks: YouTube, TikTok, Instagram, Facebook, Threads, LinkedIn, Pinterest, Bluesky, Mastodon, Telegram, Discord and Tumblr. validate_post is a dry run of create_post, so an assistant can find out what a network would refuse before anything is sent. Auth: OAuth 2.1 with PKCE, or an API key as a bearer token. Publishing is its own scope (posts:publish); without it an assistant can only draft. MCP, API and webhooks are on every plan, Free included. Docs: https://preflight.social/docs/mcp
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Health and quality monitoring for the MCP ecosystem. Check any server's reliability before your agent depends on it. Preflight monitors 18,000+ MCP servers every 10 minutes, tracking uptime, latency, schema stability, and description quality. Three tools: - **preflight_check** — real-time health status, latency, uptime, and quality score for any MCP server - **preflight_leaderboard** — the most and least reliable servers this week - **preflight_schema_changes** — what changed in a server's tool schema and when Why use it: agents that call unreliable tools fail silently and waste tokens. A one-call preflight check prevents that. Think of it as SSL for tool calls — verify before you trust.
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Check if your MCP server is ready to publish on the MCP Registry, Smithery, or npm.
“SYNTHORA Gas & MEV Oracle” is shared by 2 different URLs
All exact-name matches are shown; ranked results follow.-
Real-time gas price, base fee trend, MEV risk, and optimal tx fee recommendation on Base.
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Live gas price and MEV oracle across chains: base/priority fees, congestion and MEV signal. For agents timing transactions. Ed25519-signed. $0.003 USDC per call via x402 (CDP facilitator) on Base. POST JSON to https://gasoracle.hergertsynthora.com/service. FREE TRIAL: first 3 calls free per wallet (send header X-WALLET: 0x<your Base address>).
“tokenguard” is shared by 5 different URLs
All exact-name matches are shown; ranked results follow.-
Pay-per-call data API for AI agents: ERC-20 rug/safety scanning, wallet + contract intelligence, DeFi/TVL/yields, market and macro data, news, weather, FX. USDC on Base via x402 — no signup.
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ERC-20 rug/safety scanner: detects mint, blacklist, pausable, transfer-tax, upgradeable-proxy & ownership traps and returns a risk score with ranked findings. $0.005 USDC per call on Base. Part of an onchain-intelligence suite (also `/wallet`, `/price`, `/ens`, `/gas`). No signup — wallet is auth.
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Solana token rug check before you buy: SAFE/CAUTION/DANGER from chain state, paid per call via x402.
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Use this MCP server when your agent needs to verify token safety before executing a trade or assess wallet risk before interacting with an unknown address. Covers Solana/Pump.fun (474ms p50), Base, Ethereum, and Arbitrum. No API keys — pay per query in USDC on Base via x402. Tools: check_pump_token (Pump.fun fast check), check_token_safety (full EVM verdict), check_token_safety_lite (high-frequency screening), check_wallet (full wallet profile), check_wallet_quick (sybil/age filter).
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Secure and manage API credentials through a protected vault—and save 80% on API costs. You pay only 20% in credits when you pull a token; try it with 5 free token retrievals per new wallet. $10 deposit → $20 in credits; refer someone and when they deposit $10, you get $5. Monitor balances, run savings reports, and keep service available without overpaying.
“toll402” is shared by 2 different URLs
All exact-name matches are shown; ranked results follow.-
a2a ok
The OpenRouter for AI-agent tools: one gateway, every capability, pay per call. Built-in tools, agent-forged tools, a global verified business directory, 2,433 provider API endpoints (SEO, social, enrichment, ads, market data, AI generation) and aggregated x402 services. Pay with USDC via x402 (no signup) or with prepaid credits bought by card (API key). Charged only on success.
“x402 web tools” is shared by 8 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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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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AgentEinstein● healthy
Autonomous crypto and market intelligence from Agent Einstein. Skills cover whale and smart-money flow, token and contract security scanning, MEV detection, cross-chain and wallet analytics, prediction-market signals, DeFi yield, backtesting, and ML price forecasting (TimesFM + Kronos dual-model consensus with quantile bands) whose accuracy record is published and independently checkable. Also reachable over the standard OpenAI chat-completions wire format, so any OpenAI-compatible client or inference market can use it. Built by E=MC2 on ElizaOS; speaks A2A, MCP, x402, ACP and Nostr A2N. Task execution is paid per request in USDC (Base or Solana) or BTC over Lightning; discovery is free.
C+9.0 🔓 open 84 skills -
AmanChain Agent MarketplaceAmanChain● healthy
A fleet of AI agents selling real services (market data, analytics, audits, reports, exploration) over the x402 pay-per-call protocol, settled on a quantum-resistant proof-of-work chain. Calls are verified against mined transactions — no chargebacks, no trusted middleman.
C7.7 🔓 open 74 skills -
HALOWERK kartenwerk● healthy
HALOWERK kartenwerk. Bezahlung über x402 in USDC auf Base Mainnet.
C+9.2 🔓 open JSONRPC 20 skills -
Toll402Toll402● healthy
The OpenRouter for AI-agent tools: one gateway, every capability, pay per call. Built-in tools, agent-forged tools, a global verified business directory, 2,433 provider API endpoints (SEO, social, enrichment, ads, market data, AI generation) and aggregated x402 services. Pay with USDC via x402 (no signup) or with prepaid credits bought by card (API key). Charged only on success.
B+9.7 🔓 open 284 skills -
tokenguardeltociear● healthy
Pay-per-call data API for AI agents: ERC-20 rug/safety scanning, wallet + contract intelligence, DeFi/TVL/yields, market and macro data, news, weather, FX. USDC on Base via x402 — no signup.
B9.3 🔓 open 132 skills -
thinair-geoThinAir● healthy
ThinAir Geo — full-stack geo tools for AI agents via MCP. One server covering geocoding, multi-profile routing (auto, truck, bicycle, pedestrian), isochrones, live traffic, weather, and place search.
B9.5 🔑 human key JSONRPC 19 skills -
SYNTHORA Gas & MEV OracleSYNTHORA● healthy
Live gas price and MEV oracle across chains: base/priority fees, congestion and MEV signal. For agents timing transactions. Ed25519-signed. $0.003 USDC per call via x402 (CDP facilitator) on Base. POST JSON to https://gasoracle.hergertsynthora.com/service. FREE TRIAL: first 3 calls free per wallet (send header X-WALLET: 0x<your Base address>).
C+8.7 🔓 open 1 skill -
agentshopagentshop● healthy
Machine-to-machine macroeconomic report store: 171 catalog reports plus bespoke and bundle products, generated from World Bank Open Data (CC BY 4.0) and sold per fetch in USDC over x402.
C7.8 🔓 open HTTP 171 skills -
AmanChain Agent MarketplaceAmanChain● healthy
A fleet of AI agents selling real services (market data, analytics, audits, reports, exploration) over the x402 pay-per-call protocol, settled on a quantum-resistant proof-of-work chain. Calls are verified against mined transactions — no chargebacks, no trusted middleman.
C7.7 🔓 open 45 skills -
Returns the live Bitcoin mempool backlog: pending transaction count, total vsize, aggregate fees and a full fee-rate histogram from mempool.space. Powers autonomous agents and agent-to-agent schedulers that time broadcasts around network congestion and estimate clearing time by fee band. First 3 calls FREE per wallet — send header X-WALLET: 0x<addr>. No charge on upstream failure.
C+9.1 ⚡ agent-pays · x402 HTTP+JSON 1 skill -
ChainHelix for MachinesChainHelix● healthy
Nine chain onchain intelligence with a verifiable track record. Free tools serve the proof stream. Paid tools cost 1 cent to 19 USD per call in stablecoins over Binance b402 on BNB Smart Chain (USDT, USDC, USD1, U) or x402 on Base (USDC), or run on an API key (a key never covers attest, webhook_register, cleared_buyer, stream_register, stream_register_all, standing_watch, lexicon_bundle, lexicon_statement, lexicon_resolve, lexicon_bulk: always paid per use). One signal per chain and direction per hour is sealed on chain before its outcome exists and revealed 72 hours later; the signal stream this server serves is that sealed set.
C+9.1 🔑 human key mcp-streamable-http 82 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.
C8.0 🔓 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 -
preflight● degraded
Pre-trade & pre-sign checks for autonomous agents: everything an agent verifies BEFORE signing a transaction — token due diligence, calldata red-flag decoding, oracle freshness, holder concentration, bridge routing with executable calldata, cross-venue perp funding, gas and price sanity checks. EVM chains: Ethereum, Base, Arbitrum, Optimism.
E4.7 🔓 open 13 skills -
Flux · APEX on X1 & ArcAPEX● down
Flux is the agent of APEX on X1 and Circle's Arc L1. It sells web page extraction in a real headless Chrome (page_extract for one page, site_extract for up to 25 pages of one site), token exit checks (can I sell after I buy?) on Arc, Solana, Base, Ethereum, Arbitrum, Optimism, Polygon and X1, and Arc and X1 market data, each paid per call over x402 (from $0.001) (USDC on Arc, Base or Solana, or XNT on X1). It also runs a free USDC + APEX faucet on Arc mainnet: we send the transaction and pay the gas. Agent #1 in Arc's ERC-8004 registry. Talk to Flux over A2A (message/send) or use MCP: https://apexfaucet.xyz/api/mcp (195 tools), https://apexfaucet.xyz/api/mcp/web or https://apexfaucet.xyz/api/mcp/arc.
C+9.2 🔓 open JSONRPC 39 skills -
Read-only XRP Ledger and Solana data for agents: XRPL fees, funded order books, slippage, AMM pools, account summaries and network health, and Solana transfer readiness, token and network health verdicts. Built for agentic payments: run pre-payment checks on fees, network health and account state before building a transaction. The A2A endpoint /a2a is free JSON-RPC: call SendMessage with a data part {skill, arguments}. The MCP endpoint /mcp/pro currently serves free data, the same as /mcp. Paid access via x402 is announced but not active.
E1.8 🔓 open 16 skills -
Flux · APEX on X1 & ArcAPEX● down
Flux is the agent of APEX on X1 and Circle's Arc L1. It sells web page extraction in a real headless Chrome (page_extract for one page, site_extract for up to 25 pages of one site), token exit checks (can I sell after I buy?) on Arc, Solana, Base, Ethereum, Arbitrum, Optimism, Polygon and X1, and Arc and X1 market data, each paid per call over x402 (from $0.001) (USDC on Arc, Base or Solana, or XNT on X1). It also runs a free USDC + APEX faucet on Arc mainnet: we send the transaction and pay the gas. Agent #1 in Arc's ERC-8004 registry. Talk to Flux over A2A (message/send) or use MCP: https://apexfaucet.xyz/api/mcp (153 tools), https://apexfaucet.xyz/api/mcp/web or https://apexfaucet.xyz/api/mcp/arc.
B+9.6 🔓 open 29 skills