# Agentropolis

> A search engine for agent-usable tools: MCP servers, x402 and MPP paid HTTP APIs, A2A agents and "kits". 52026 listings. Trust scores come only from verified, non-wash payments. Agentropolis is never a party to transactions: buyers pay sellers directly (x402/Coinbase, MPP, Stripe). No splits, referral fees or proxying.

Search returns organic `results` ranked by relevance and payment-verified trust; Agentropolis first-party kits appear only in the labelled `featured_first_party` array. `trust.score: null` means no payment evidence, not a bad tool. Always trust the seller's live HTTP 402 challenge over any listed price. Full reference in one file: https://agentropolis.io/llms-full.txt

## Docs
- [llms-full.txt](https://agentropolis.io/llms-full.txt): this index plus the full reference (API, MCP tools, rules, badges, free allowance, x402 pass-through) and the data behind every topic and comparison page
- [OpenAPI](https://agentropolis.io/openapi.json): REST API (search, listings, kit manifests, stats, reports, badges)
- [MCP server](https://agentropolis.io/api/mcp): Streamable HTTP, no auth, read-only search tools plus call_kit (forwards to an x402 seller, never pays)
- [A2A agent card](https://agentropolis.io/.well-known/agent-card.json): JSON-RPC at https://agentropolis.io/a2a (message/send)
- [API catalog (RFC 9727)](https://agentropolis.io/.well-known/api-catalog)
- [Install](https://agentropolis.io/install): Claude Code, Cursor, VS Code, AI SDK, LangChain, CrewAI, OpenAI Agents SDK
- [Trust method](https://agentropolis.io/api/v1/trust/method): how the 0-100 trust score is computed from wash-filtered on-chain payments
- [kit.json v0.1 schema](https://agentropolis.io/spec/kit-v0.1.json) and [first-party kits index](https://agentropolis.io/.well-known/kits.json)

## Search
- [Search API](https://agentropolis.io/api/v1/search?q=web+search&rail=x402&max_price_usd=0.05&min_trust=40): params q, kind (mcp_server, http_api, a2a_agent, kit), category, rail (x402, mpp, stripe), max_price_usd, min_trust, limit
- [Listing JSON](https://agentropolis.io/api/v1/listings/x402.exa): GET /api/v1/listings/{id}; kit manifest at /api/v1/listings/{id}/kit.json; HTML at /listing/{id}
- [Web search UI](https://agentropolis.io/?q=weather)

## Answers (topic pages from real searches)
- [Agent-to-agent micropayment APIs](https://agentropolis.io/topics/agent-micropayments): Pay-per-call APIs, facilitators and MCP servers that let AI agents pay each other in small amounts, with their payment rail, listed price and payment-verified usage from the Agentropolis index.
- [Nano (XNO) payments for agents](https://agentropolis.io/topics/nano-xno-payments): Listings in the Agentropolis index that accept or work with Nano (XNO) payments, feeless transfers or Nano invoices, with what we can and cannot verify about each. (thin: few listings with evidence yet)
- [SEO and backlink tools agents can use](https://agentropolis.io/topics/seo-backlink-tools-for-agents): MCP servers and pay-per-call APIs for backlink data, keyword research, rank tracking and AI-search visibility, from the Agentropolis index, with remote-endpoint and payment evidence where it exists.
- [Weather APIs for AI agents](https://agentropolis.io/topics/weather-apis-for-ai-agents): Weather and forecast APIs and MCP servers an AI agent can call, ranked by payment-verified usage, with listed prices per call and uptime where measured.
- [Image generation for agents](https://agentropolis.io/topics/image-generation-apis-for-ai-agents): Image generation MCP servers and pay-per-call image APIs an AI agent can call, with listed price per image and payment-verified usage where it exists.
- [Pitch and intro-video script tools for agents](https://agentropolis.io/topics/video-pitch-script-tools-for-agents): APIs and MCP servers that write elevator pitches, video-resume scripts and intro videos, plus our own Pitch Kit (labelled, first-party). (thin: few listings with evidence yet)
- [Payload validation and junk filters for agents](https://agentropolis.io/topics/json-validation-junk-filter-apis-for-agents): APIs and MCP servers that validate JSON against a schema, repair malformed output, or flag junk scrapes and captcha pages before an agent acts on them, plus our own Payload Check (labelled, first-party).
- [Whale tracking and liquidation data for agents](https://agentropolis.io/topics/whale-tracking-liquidation-apis-for-agents): APIs and MCP servers for whale wallets, smart-money flows, funding rates and liquidation levels, ranked by payment-verified usage, plus our own Whale Radar (labelled, first-party).
- [Payment guards and seller reputation for agent wallets](https://agentropolis.io/topics/x402-payment-guards-and-seller-reputation-for-agents): APIs that check an x402 402 challenge before an agent pays (wallet↔domain, price, lookalike URL, wash flags) and score seller wallets, plus our own Pay Guard (labelled, first-party).
- [Short video clip and image-to-video APIs for agents](https://agentropolis.io/topics/short-video-clip-apis-for-agents): Paid APIs agents can call to turn an image or prompt into a short vertical or widescreen clip, plus our own Short Video Clip kit (labelled, first-party).

## Comparisons
- [Transcription APIs for AI agents, compared](https://agentropolis.io/compare/best-transcription-apis-for-ai-agents): Speech-to-text and transcription APIs and MCP servers an agent can call, compared on listed price, payment rail and on-chain verified usage. Our own kit, Transcript+, is first-party and shown separately.
- [x402 vs Stripe for agent payments](https://agentropolis.io/compare/x402-vs-stripe-for-agent-payments): How x402 and Stripe machine payments (MPP, cards via Shared Payment Tokens, stablecoins) compare for selling an API to AI agents: published fees, minimum charge, settlement and what the Agentropolis index shows about real usage.
- [Web search for agents: MCP servers vs pay-per-call APIs](https://agentropolis.io/compare/best-mcp-servers-for-web-search): Web search MCP servers (remote endpoints first) and x402 pay-per-call search APIs from the Agentropolis index, compared on connection type, listed price and payment-verified usage.
- [Token safety / honeypot check APIs for agents](https://agentropolis.io/compare/token-safety-check-apis-for-agents): APIs and MCP servers that check an ERC-20 or Solana token for honeypots, rug-pull signals or contract risks before an agent trades, compared on price, rail and verified usage. Our own Token Preflight and Trade Preflight kits are first-party and shown separately.
- Disclosure: Agentropolis's own kits on these pages are labelled first-party and never ranked.

## Categories
- [Security & verification](https://agentropolis.io/categories/security-verification): 4,690 listings, 123 with payment-verified usage, median listed price $0.01
- [Crypto & on-chain data](https://agentropolis.io/categories/crypto-onchain-data): 2,264 listings, 85 with payment-verified usage, median listed price $0.01
- [People & company enrichment](https://agentropolis.io/categories/people-company-enrichment): 3,247 listings, 59 with payment-verified usage, median listed price $0.005
- [LLM inference](https://agentropolis.io/categories/llm-inference): 3,141 listings, 57 with payment-verified usage, median listed price $0.002
- [Media: speech, video & image](https://agentropolis.io/categories/media-speech-video-image): 3,156 listings, 50 with payment-verified usage, median listed price $0.005
- [Web search](https://agentropolis.io/categories/web-search): 5,400 listings, 40 with payment-verified usage, median listed price $0.01
- [Scraping & extraction](https://agentropolis.io/categories/scraping-extraction): 1,637 listings, 36 with payment-verified usage, median listed price $0.005
- [Social data](https://agentropolis.io/categories/social-data): 1,423 listings, 30 with payment-verified usage, median listed price $0.01
- [Finance & markets](https://agentropolis.io/categories/finance-markets): 2,171 listings, 22 with payment-verified usage, median listed price $0.01
- [Travel](https://agentropolis.io/categories/travel): 816 listings, 10 with payment-verified usage, median listed price $0.0085
- [Compute & infra tools](https://agentropolis.io/categories/compute-infra-tools): 2,532 listings, 8 with payment-verified usage, median listed price $0.01
- [Reports & research](https://agentropolis.io/categories/reports-research-intel): 1,250 listings, 8 with payment-verified usage, median listed price $0.01
- [Developer tools](https://agentropolis.io/categories/developer-tools): 13,060 listings, 4 with payment-verified usage, median listed price $0.03
- [Off-ramp, gift cards & payouts](https://agentropolis.io/categories/offramp-giftcards-payouts): 115 listings, 4 with payment-verified usage, median listed price $0.01
- [Productivity & docs](https://agentropolis.io/categories/productivity-docs): 509 listings, 3 with payment-verified usage, median listed price $0.002
- [All categories](https://agentropolis.io/categories) (thin categories are listed there but not indexed)

## Market data (wash-filtered; data: x402-list.com CC BY 4.0)
- [Live stats](https://agentropolis.io/stats): JSON https://agentropolis.io/api/v1/stats ; chart https://agentropolis.io/stats/chart.svg
- [State of paid agent tools, 2026-44](https://agentropolis.io/reports/2026-44): JSON https://agentropolis.io/api/v1/reports/2026-44
- [State of paid agent tools, 2026-43](https://agentropolis.io/reports/2026-43): JSON https://agentropolis.io/api/v1/reports/2026-43
- [State of paid agent tools, 2026-42](https://agentropolis.io/reports/2026-42): JSON https://agentropolis.io/api/v1/reports/2026-42
- [State of paid agent tools, 2026-41](https://agentropolis.io/reports/2026-41): JSON https://agentropolis.io/api/v1/reports/2026-41
- [All reports](https://agentropolis.io/reports) ; [RSS](https://agentropolis.io/reports/rss.xml)

## Sellers
- [Claim a listing](https://agentropolis.io/sellers): email sign-in; verify via /.well-known/agent-hub-verify.txt, DNS TXT or email at your domain
- [Badges](https://agentropolis.io/badges): Verified, Live-Tested, Trusted (earned); Agentropolis Pro (paid, coming soon, no charges enabled)

## Optional
- [Sources and terms](https://agentropolis.io/sources) ; JSON https://agentropolis.io/api/v1/sources
- [Privacy](https://agentropolis.io/privacy): no raw IPs; bots and crawlers are labelled and excluded from seller stats
- [Roadmap](https://agentropolis.io/roadmap) ; [Business model](https://agentropolis.io/api/v1/business-model)
- [Examples repo](https://github.com/seenly721/agentropolis-examples)
- Contact: hello@agentropolis.io (read by a human)