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Paid ComfyUI knowledge tools. 5 tools $0.005 USDC/call on Base via x402; ping, list_topics free.

Pay-per-document knowledge packs for AI agents: risk checklists, agent-ops methods, research protocols, and production guides. Priced in USDC on Base via x402 (exact scheme).

Pharos Atlas provides structured editorial references for trade and blue-collar topics. Its paid x402 resources give researchers, developers, and AI agents defined reference material with stated scope, source context, and limitations. Each listing describes the specific resource being purchased.

Production-ready zero-knowledge proof generation with x402 micropayments on Base L2

e-Cognocracy Stage 19/20 task record — the knowledge extracted and value created by one completed, monitored task. The only external, non-member access path to this data — the free Stage 19 governance

Professional Avid Media Composer post-production workflow knowledge for AI agents and editorial systems.

Send a link, know it: any URL — article, YouTube video, X post, podcast episode, paper, PDF, GitHub repo — becomes a durable, cited knowledge page plus a token-efficient markdown packet built for agent relay. Flat $0.01 per link. Links are unique: anything any agent has ever known answers instantly from the shared knowledge base; first-ever links are processed once, for everyone (we absorb tran...

Verify any text data using the Cybercentry Private Data Verification API with x402 payment protocol. Returns Zero-Knowledge Proof (ZKP) verification details.

Trivia Daily knowledge challenge — answer one deterministically selected and shuffled question from a curated local set.

Search GAMEMAXXING's video games and gaming knowledge base for game concepts across game design, game business, game culture, and gaming history, then return ranked JSON hits with full content first and source URLs second.

Autonomous cognitive kernel, sub-millisecond associative memory, AER-1 execution notarization, and zero-knowledge state crystal vault. Local-first WhiteMagic runs on-device; this hosted lane provides machine-to-machine recall, execution verification, and uncollateralized compute trade credit over x402 and MCP.

Track real-time changes to the crypto knowledge graph — new tokens listed, protocol metrics updated, investor relationships added, governance proposals created. Monitor the pulse of the crypto ecosystem as data flows in from multiple sources daily | ZWING Intelligence (https://zwing.finance) — contact: [email protected], Telegram: @valery_zzz

Knowledge bookstore for AI agents: structured OKF knowledge bundles bought over x402. USDC on Base via CDP facilitator, gasless for the buyer; sealed zips with sha256 + signed receipts; open negentropy pricing formula. One free foundation bundle for ~1 month (founding-member on-chain record). Bazaar discovery extension on 402 responses. No API keys, no signup. ([Catalog](https://negbit.com/catalog.json)) ([llms.txt](https://negbit.com/llms.txt)) ([agents.txt](https://negbit.com/agents.txt))

Publish openly licensed AI agent state, knowledge, or discoveries to the permanent Agent Immortality library.

This agent verifies exactly one factual claim against a supplied source text. It does not perform web searches, does not use external knowledge, and does not infer facts from branding. The verification is strictly limited to the provided project text and RAG context to ensure 100% adherence to the source material without hallucinations or outside interference.

The knowledge marketplace for agents. Publish once and earn every time an agent uses your work.

Japanese dream-interpretation agent API. Returns a Gemini-generated full interpretation from madoromi's curated dream-motif knowledge base (result schema agent-dream-insight.full.v1). Japanese output only. Dream text is never stored or logged. Async by default: the paid POST returns a job id in seconds; fetch the result with a plain free HTTP GET (no x402 client) at /api/agent/interpret/result/...

NVIDIA AI knowledge graphs — 20 domains. 4x F1, 11x fewer tokens, SHA-256 provenance. MCP-native.

A portable knowledge-graph memory you pass in and get back. No database. 4 of 6 free.

NVIDIA NemoClaw knowledge graph — 55 nodes, F1 0.576 (+269% vs RAG), 11x fewer tokens. MCP-native.

Verifies the main factual claims in a proposed news article strictly against source texts supplied by the buyer. It does not browse the web or use outside knowledge.

url.ventures is a digital asset owner intelligence system: one machine that turns ownership activity into compounding knowledge of what digital property is worth.

Multi-agent AI orchestration with x402 micropayments. 49 endpoints, 39 MCP tools, knowledge/RAG. ([npm](https://www.npmjs.com/package/swarms-x402)) ([Live](https://swarmx.io))

Open-source knowledge marketplace with x402 payment gate on Solana. AI agents discover and purchase human expertise via MCP server with autonomous x402 payment flow. ([GitHub](https://github.com/Sou0327/knowmint))

ZK-private HTTP payments for x402. Adds sender privacy via Noir zero-knowledge proofs on Base, so AI agents and API consumers can pay without exposing wallet balances or transaction history. ([GitHub](https://github.com/BermudaBay/sdk))

Data visualization and research platform. Search Tako's curated data and the web for citation-backed knowledge cards, get cited answers, download the data behind a result, chart your own CSV, and run deep-research agents.

Richard Hobbs' AI agent. Fashion tech intelligence across 30+ years: denim, streetwear, luxury, performance, 3D product creation, digital fashion, agentic commerce. Operates a knowledge marketplace and the Real Real Genuine (RRG) NFT co-creation platform. Accepts USDC on Base mainnet.

The Family Office Knowledge Graph index of record for $0.01 USDC — every node's record list (LEI, legal name, aliases, register ids, field states, as-of) as a signed statement (EdDSA, kid fo-kg-x402-2026-09) with a receipt that resolves forever at /x402/receipt/{nonce}. Operator: Agentic KG Holdings.

Market where AI agents sell what they measured: knowledge units (benchmarks, failure post-mortems, working parameters) reviewed against their evidence, and versioned, signed datasets. Each paid read is one x402 payment in USDC; search, listings and free reads need no payment or key. Remote MCP server at https://witan.markets/mcp, OpenAPI at https://witan.markets/openapi.json, Python and JS SDKs. P

Formal verification for AI agent actions using the ARc paper approach. Natural language policies compile to SMT-LIB formal logic, checked by an SMT solver — SAT = allowed, UNSAT = blocked. Wrapped in zero knowledge proofs for sub-1s verification, private policies, and cryptographic audit trails per decision. 99%+ soundness under adversarial pressure. $0.10 USDC per check on Base, no account needed. Live demo policy available.

Music oracle for AI agents — chord, song, progression, practice. Canonical chord knowledge, song analysis, practice planning, and progression transcription, sourced from verified theory and attested song data. Pay per call in USDC on Base (x402) or USD via Stripe Checkout.

Analyze Google search results for a keyword. Returns organic results, featured snippet, People Also Ask, SERP features. Google SERP analysis for SEO and keyword research: ranking pages, featured snippet owner, PAA questions, related searches, and which SERP features appear (knowledge graph, AI overview, videos, shopping, local pack, ads), by country and language.

Free web-based scanner that validates x402 implementations on any URL (HTTP 402 with quoted price headers, payment-required surface, well-known/x402 discovery, agent-readable pricing) alongside ~70 other agent-readiness checks. Per-check remediation hints linked to a Knowledge Base. Also available as a [CLI](https://github.com/Agentic-Adventures/agentgrade-cli), [MCP server](https://agentgrade.com/mcp), and [GitHub Action](https://github.com/marketplace/actions/agentgrade-scan). Public leaderboard at [agentgrade.com/leaderboard/](https://agentgrade.com/leaderboard/).

People + life-in-days knowledge for AI agents. Public MCP; x402 on Base; OAuth for private tools.

Live web search results. $0.01 USDC per call on Base, no API key. GET ?q=... (required), count 1-20 (default 10), optional country, language, page. Returns results[{ title, url, description, score }], plus Google's answer box, knowledge graph, people-also-ask, related searches and shopping when the Google-backed provider answers (empty on fallback).

Structured research brief from model-knowledge synthesis (qwen2.5:14b). No live web research. POST {topic, questions?: [str] (max 5)} -> {overview, key_points: [..], open_questions: [..], caveats}.

AI agent providing 21 payment-gated endpoints for AI-powered services: consultation, knowledge recall, chatbot development, workflow automation, character generation, UI/UX design, long-form Q&A, MCP evaluation, negotiation simulation, puzzle generation, RAG pipelines, Monte Carlo simulation, SQL generation, spreadsheet automation, story generation, time-series analysis, web agent planning, worldbuilding, competitive benchmarking, and workflow automation. All endpoints use the x402 v2 protocol for agent-native HTTP payments (USDC on Base mainnet).

Live data API for AI agents. 9 free endpoints + 42 paid endpoints covering finance, travel, weather, location, news, commerce, knowledge, content, and agent utilities. x402 micropayments via PayAI facilitator on Base, Polygon, Arbitrum, Avalanche, Sei, Solana.

AI memory buyer routing with Forge docs, pricing, enterprise intake, and MCP discovery.

MCP tool for governed nonclinical pattern interruption, emotional clarity, and next-step guidance.

5 AI agent verification endpoints (NoLeak, MemGuard, RiskOracle, SecureExec, FlowCore) on Base Mainnet. $0.01-$0.02 USDC per call via x402.

uptime_30d 0.9231%; p95 871.7ms; conformance: pass

5-pillar agent identity and access layer with 9 x402-payable verification endpoints: NoLeak (execution integrity), MemGuard (memory state verification), RiskOracle (pre-action risk scoring), SecureExec (tool execution security), and FlowCore (full orchestration pipeline). $0.01-$0.02 USDC per call on Base. All 9 endpoints verified healthy on [402index.io](https://402index.io). Agent discovery via [/.well-known/agent.json](https://achillesalpha.onrender.com/.well-known/agent.json) and [/.well-known/mcp.json](https://achillesalpha.onrender.com/.well-known/mcp.json). ([Docs](https://achillesalpha.onrender.com/docs)) ([Quickstart](https://achillesalpha.onrender.com/quickstart))

Read-only x402 research APIs. No trading, broker, or execution is exposed.

The AI will perform actions like searching and browsing web pages to find the answer to the provided task. Execution time is 3-30s depending upon complexity. For longer tasks, use the agent endpoint instead.

Board-game and tabletop intelligence: group-profile recommendations, head-to-head comparisons, expansion checks, collection valuation, crowdfunding back-vs-wait…

x402 market intel: providers ranked by real payers; seller vetting; schema drift. $0.01 auto-pay.

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PDF to text: give a PDF URL, get the text of every page with the title, author and page count. For RAG, research and summarizing reports, filings and papers.

Crypto backtesting & Bitcoin cycle analytics. Point-in-time, DSR-corrected, look-ahead-aware.

Search US CFPB consumer complaint records across banks, lenders, and fintech institutions.

Use when an agent cannot sign x402 payments (OpenAI, Grok, Perplexity, Mistral, Copilot Studio, Gemini Enterprise): buy a $1 prepaid access key with one x402 payment, then send it as Authorization: Bearer on any paid route or /mcp tools/call; each call is deducted at its listed price. Shown once; balance is free at /keys/balance; top up with the same header (cap $100). Unused access-key balance ne. Pay per call $1 via x402 (USDC on Base, Arbitrum, Polygon, Avalanche, Optimism, Celo or Ethereum; USDT0 on Arbitrum; sBTC on Stacks); no account needed. Not using x402? Pay directly in USDC, USDT, DAI, WETH (Base, Ethereum, Polygon, Arbitrum); ETH (Base, Ethereum, Arbitrum); POL (Polygon); cbBTC (Base); WBTC (Ethereum, Polygon, Arbitrum); BTC (Bitcoin); SOL, USDC, USDT (Solana); STX, sBTC (Stacks); TRX, USDT (TRC20) (TRON), then claim the call with the transaction id (?tx=, ?btc=, ?tron=, ?sol= or ?stx=). Addresses and steps: https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/pay. Run by an ecosystem of AI agents (P0).

Use when an agent cannot sign x402 payments (OpenAI, Grok, Perplexity, Mistral, Copilot Studio, Gemini Enterprise): buy a $20 (+10% bonus: $22 of calls) prepaid access key with one x402 payment, then send it as Authorization: Bearer on any paid route or /mcp tools/call; each call is deducted at its listed price. Shown once; balance is free at /keys/balance; top up with the same header (cap $100). Pay per call $20 via x402 (USDC on Base, Arbitrum, Polygon, Avalanche, Optimism, Celo or Ethereum; USDT0 on Arbitrum; sBTC on Stacks); no account needed. Not using x402? Pay directly in USDC, USDT, DAI, WETH (Base, Ethereum, Polygon, Arbitrum); ETH (Base, Ethereum, Arbitrum); POL (Polygon); cbBTC (Base); WBTC (Ethereum, Polygon, Arbitrum); BTC (Bitcoin); SOL, USDC, USDT (Solana); STX, sBTC (Stacks); TRX, USDT (TRC20) (TRON), then claim the call with the transaction id (?tx=, ?btc=, ?tron=, ?sol= or ?stx=). Addresses and steps: https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/pay. Run by an ecosystem of AI agents (P0).

Use when you need natural-hazard context for a site by latitude/longitude: active NWS alerts at the point (US only), USGS earthquakes and open NASA EONET events (fires, storms, volcanoes, floods) within a radius, each with distance_km, magnitude, time and link. A failed source is listed, not hidden. $0.005 per call (USDC or USDT). Or pay directly in BTC, ETH, USDT, SOL, TRX or STX (sub-cent: stabl. Pay per call $0.005 via x402 (USDC on Base, Arbitrum, Polygon, Avalanche, Optimism, Celo or Ethereum; USDT0 on Arbitrum; sBTC on Stacks); no account needed. Not using x402? Pay directly in USDC, USDT, DAI, WETH (Base, Ethereum, Polygon, Arbitrum); ETH (Base, Ethereum, Arbitrum); POL (Polygon); cbBTC (Base); WBTC (Ethereum, Polygon, Arbitrum); BTC (Bitcoin); SOL, USDC, USDT (Solana); STX, sBTC (Stacks); TRX, USDT (TRC20) (TRON), then claim the call with the transaction id (?tx=, ?btc=, ?tron=, ?sol= or ?stx=). Addresses and steps: https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/pay. Run by an ecosystem of AI agents (P0).

Use when you must profile an IP address in one call: ASN, AS name and country of its announced range, whether it is a current Tor exit node, and whether it lies in a public cloud range (AWS, Google Cloud, Cloudflare, Oracle) with service and region. IPv4 or IPv6; open datasets, dated and credited. $0.003 per call (USDC or USDT). Or pay directly in BTC, ETH, USDT, SOL, TRX or STX (sub-cent: stablec. Pay per call $0.003 via x402 (USDC on Base, Arbitrum, Polygon, Avalanche, Optimism, Celo or Ethereum; USDT0 on Arbitrum; sBTC on Stacks); no account needed. Not using x402? Pay directly in USDC, USDT, DAI, WETH (Base, Ethereum, Polygon, Arbitrum); ETH (Base, Ethereum, Arbitrum); POL (Polygon); cbBTC (Base); WBTC (Ethereum, Polygon, Arbitrum); BTC (Bitcoin); SOL, USDC, USDT (Solana); STX, sBTC (Stacks); TRX, USDT (TRC20) (TRON), then claim the call with the transaction id (?tx=, ?btc=, ?tron=, ?sol= or ?stx=). Addresses and steps: https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/pay. Run by an ecosystem of AI agents (P0).

Use when you must screen several sites for natural hazards at once: up to 10 'lat,lon' points in one POST, each answered exactly like /hazards/near (NWS alerts in the US, USGS earthquakes, NASA EONET events with distances). Fixed price per call for 1 to 10 sites ($0.005 each at a full batch); bad input refused before any charge. $0.05 per call (USDC or USDT). Or pay directly in BTC, ETH, USDT, SOL. Pay per call $0.05 via x402 (USDC on Base, Arbitrum, Polygon, Avalanche, Optimism, Celo or Ethereum; USDT0 on Arbitrum; sBTC on Stacks); no account needed. Not using x402? Pay directly in USDC, USDT, DAI, WETH (Base, Ethereum, Polygon, Arbitrum); ETH (Base, Ethereum, Arbitrum); POL (Polygon); cbBTC (Base); WBTC (Ethereum, Polygon, Arbitrum); BTC (Bitcoin); SOL, USDC, USDT (Solana); STX, sBTC (Stacks); TRX, USDT (TRC20) (TRON), then claim the call with the transaction id (?tx=, ?btc=, ?tron=, ?sol= or ?stx=). Addresses and steps: https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/pay. Run by an ecosystem of AI agents (P0).

Use when you must refresh or screen many companies by LEI (KYB, vendor or counterparty lists): up to 200 LEIs in one POST, read from GLEIF in one call: legal name, status, addresses, registration dates, last_update_date and a record_hash that shows a change. Fixed price per call for 1 to 200 LEIs; bad input refused before any charge. $0.02 per call (USDC or USDT). Or pay directly in BTC, ETH, USDT. Pay per call $0.02 via x402 (USDC on Base, Arbitrum, Polygon, Avalanche, Optimism, Celo or Ethereum; USDT0 on Arbitrum; sBTC on Stacks); no account needed. Not using x402? Pay directly in USDC, USDT, DAI, WETH (Base, Ethereum, Polygon, Arbitrum); ETH (Base, Ethereum, Arbitrum); POL (Polygon); cbBTC (Base); WBTC (Ethereum, Polygon, Arbitrum); BTC (Bitcoin); SOL, USDC, USDT (Solana); STX, sBTC (Stacks); TRX, USDT (TRC20) (TRON), then claim the call with the transaction id (?tx=, ?btc=, ?tron=, ?sol= or ?stx=). Addresses and steps: https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/pay. Run by an ecosystem of AI agents (P0).

Retrieves comprehensive Amazon product data by ASIN including title, price, ratings, photos, variations, best sellers rank, buy box details, and seller offers across multiple Amazon marketplaces.

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