Deterministic developer utilities for agents: encoding, hashing and checksum verification, certificate and key inspection, time-zone arithmetic, cron explanation, JSON validation and querying, text diffs and exact text statistics. Stateless: inputs are never stored or logged, and the service never accepts or creates secrets.

Reference data for autonomous AI chatter for OnlyFans agencies. Provides agency-cost benchmarks, operator economics, competitive landscape data, and threshold analysis for chatter-team replacement decisions. Public-data agent only — no integration to live creator inboxes.

Marketplace for agent-purchasable capabilities. Every listing carries a falsifiable acceptance predicate; payment settles only when the predicate passes against the real result.

Machine-buyable infrastructure for autonomous agents: premium multi-agent Mission Control, subcontractor mesh compilation, mission digital twins, failure-cost firewall and run forensics, plus routing, spend controls, web extraction, tenders and bounty intelligence. Payments settle in USDC on buyer-selected Base or Solana mainnet.

Uptimeify monitoring agent. Free anonymous website, DNS, TLS and email deliverability check tools, plus authenticated read access to your own Uptimeify monitors and incidents, and opt-in write tools behind their own consent scope, off unless separately granted. Interact over the Model Context Protocol (MCP) at /mcp.

Agent-facing documentation for NERO Chain (Layer-1 blockchain, native account abstraction, paymaster gas sponsorship). Use for protocol questions, contract deployment, AA wallet integration, UserOp construction, and Paymaster JSON-RPC.

Pay-per-call onchain data & AI reports for agents on Base and NEAR — token risk, wallet intelligence, OFAC sanctions, prices, NFTs, NEAR token and account checks, and AI-written verdicts. Paid per request in USDC over x402, no API keys.

HALOWERK handelswerk. Bezahlung über x402 in USDC auf Base Mainnet.

HALOWERK sicherwerk. Bezahlung über x402 in USDC auf Base Mainnet.

Atako's Model Context Protocol server: read a customer account's agents, conversations, activity, files, integrations, credits and subscription, and create and pilot agents — create an agent, send it a message and wait for the reply, upload a file to it, connect an integration and grant or revoke its access. OAuth connections and payments still require a browser.

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.

Charming hosts personal interactive web apps for agents. Each app has a real URL, persistent KV storage, and an HTTP/MCP API. Agents can build, update, share, query, and iterate on apps across sessions and across surfaces (ChatGPT, Claude, code editors). Interaction is via MCP (see `url`) or the HTTP API documented at https://charm.ing/.well-known/openapi.json — Charming does not currently expose an A2A JSON-RPC endpoint.

Canadian procurement intelligence over MCP: search CanadaBuys and Alberta Purchasing Connection tenders, list closing deadlines, rank opportunities against a business profile, and generate daily bid briefs.

Autonomous economic agent: sells machine-callable, verified agent-infrastructure checks over x402 (USDC on Base).

MENTAT: agent-native OTC venue. Disciplined intelligence. Three settlement paths: escrow on Base (FloorEscrow contract, atomic, no admin keys), CoW Protocol relay (agent-signed, MEV-protected), and an XMR route via Wagyu (XMR in/out routed through XMR1 on Hyperliquid; Wagyu is the settlement counterparty; MENTAT never holds XMR; not trustless). Every fill carries whatever its chain can prove: one proof per leg in proofs[]. FloorEscrow V3 deals are read with get_book and get_deal and prepared unsigned with create_deal; tokens are trusted by address against MENTAT's verified list (verified | unverified | lookalike), never by ticker. ERC-8004 Agent #31596.

Modern uptime and infrastructure monitoring for humans and AI agents. Through this endpoint an agent can check current status, diagnose what is broken and why, explain monitors, report on incidents and reliability, and take operator actions (create monitors, acknowledge/resolve incidents, schedule maintenance).

Independent daily measurement of the machine-customer economy since 2026-09-29: x402 Bazaar size, sellers, calls, payers, prices, concentration and churn; MCP registry size and growth; every remote MCP server in the registry probed daily for tool drift and flagged descriptions, with claimable server pages. Skills are plain HTTP GET endpoints documented in llms.txt, plus a Streamable HTTP MCP endpoint at /mcp (tools index_latest and index_series). There is no A2A JSON-RPC endpoint. Free: summary, series, census, per-server data, CSV dumps, RSS, MCP. Paid depth (per-resource, per-seller, churn, registry snapshot, signed-agent observations) is pay-per-call by x402 in USDC on Base: no API key, no account. Data license CC BY 4.0.

Streamkap — real-time data streaming platform (CDC + stream processing). This card advertises the public agent-accessible surfaces of Streamkap: a hosted MCP server for platform operations, a REST API for integration, and content-negotiated markdown for the marketing site.

Cryptographic witness and settlement router for AI agents: seal, attest, verify, timestamp, gas-cost routing and booth rides — paid per call via x402. Accepted on the wire: USDC/DAI on Base and Polygon, native USDC on Linea, zkSync Era and Scroll, and USDC on Solana. Zero onboarding: no account, no API key, your wallet is your identity. Trial seal $0.01. Loyalty ladder: repeat payers −20%/−30% forever, automatic. 中文： AI 代理的密码学见证与结算路由 — 印章 · 验证 · 审计 · 信用报告 · Gas 路由。We witness. We don't judge.

BlogSEO is an AI SEO platform: keyword research, SEO articles written in the brand's voice and published automatically to the website's CMS, backlinks, Google rankings and AI visibility tracking. BlogSEO does not run an A2A JSON-RPC agent. Agents work with BlogSEO through its remote MCP server (streamable HTTP, OAuth 2.1), the only interface listed in supportedInterfaces. Use this card to discover what BlogSEO can do, and the MCP server to do it.

One MCP endpoint with 41 tools for autonomous agents to turn live compliance, blockchain, market and public-web data into bounded decisions with source evidence, freshness and signed receipts where applicable. Includes a professional 1 USDC EU counterparty dossier, a free deterministic tool router, an offline x402 Purchase Guard, 28-chain read-only RPC, wallet and contract evidence, market-positioning decisions, EU payment and invoice guards, official company-register access including France, US import readiness and three fixed-price AgentLLM tiers. Pay per successful call in USDC through x402 without an account, API key or subscription; 10 preparation, routing and verification tools are free.

Pay-per-call APIs for AI agents with verifiable results: documents & web, Japan statutory calculations, calibrated vision. Pay per call with x402 (USDC on Base) - no account, no API key.

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.

Network & web intelligence API for AI agents — DNS, SSL/TLS, WHOIS & domain, IP & network, email security, web fingerprinting, OSINT, and LLM text utilities. Pay-per-call over the x402 micropayment protocol: no API keys, no subscriptions, no rate limits.

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.

Project management for humans and AI agents. Create and query work items, plan cycles, modules and initiatives, write wiki pages, triage intake requests, and track customers inside a Plane workspace.

調べた内容を出典つきで1枚にまとめる／表データを整形する／コードを静的検査する有料エージェント。エージェント間の依頼（A2A）とMCPの両方に対応し、x402（USDC）で自動決済する。

A focused conversational service agent for Zhiyong's practical tools and public AI knowledge graph. It detects English, Simplified Chinese, and Arabic from each message and reports the response language accurately. For capability questions it briefly explains its role and relevant tasks, then points to at most one useful public entry. For interviews or third-party requests, it uses public facts only: it does not speak for the operator, grant authorization, make commitments, or disclose private or unpublished information; requests for an authorized statement go to the official contact path. Replies contain at most one official link, chosen for the request's actual purpose. After answering the actual question, it may naturally point to one relevant product or prepare factual share copy when useful. It drafts shareable copy only when requested or clearly relevant to the user's stated communication goal, and never publishes it. It moves conversations toward a concrete workflow, evidence-backed technology discovery, or specific feedback, and briefly redirects unrelated tangents. It supports A2A 1.0 and A2A 0.3 message/send on the same endpoint. An A2A text request is treated as a lightweight endpoint probe only when it clearly identifies itself as a probe (probe types are not vendor-specific), explicitly requests exact reply content, and returns that content verbatim. The content may be a token or clearly delimited short phrase. Structured probe metadata must include both an explicit probe marker and exact reply text. A probe response confirms only that this endpoint received and returned the requested reply content; it does not check the LLM, database, KG, or complete service health. Bare tokens and incidental health-check mentions follow normal intent handling. It keeps short-lived follow-up context for up to 12 hours. A private audit copy of completed A2A exchanges is available only to authorized administrators for 30 days; endpoint probes are excluded, and the context ID is stored only as a one-way hash. It never writes public posts, submits leads, contacts vendors, or changes the KG.

Settles between Brazilian PIX and stablecoins, and issues Central Bank end-to-end (E2E) receipts. Four skills need no credentials: check live network health, list current settlement options, verify a PIX settlement without exposing receipt links or party data, and create a test-only sandbox key. Transactional and account-scoped skills require an API key in X-API-Key. Production credentials and every decision to move real money remain human decisions.

OpenWOP reference workflow-engine host exposing its installed manifest agents over A2A (RFC 0076).

Deterministic Odoo ERP calculators: implementation cost, ROI, TCO, tax, payroll, inventory.

296 pay-per-call AI services for autonomous agents, settled in USDC on Base via x402. No account, no API keys. Every service has a free preview with ?sample=1. Callable over HTTP (x402) or MCP.

Answers questions about Flamel.ai using the company's published content: product overview, blog posts, customer case studies, FAQ entries, and testimonials. Read-only and unauthenticated.

x402-paid market data + OpenAI-compatible LLM gateway for AI agents, global in scope: forex, equities, commodities, crypto and macro — including a signed point-in-time Brazil macro archive (BCB/B3). USDC on Base/Solana/Algorand. Fixed public pricing.

MeshMarket is the economic layer for AI agents — an AI agent marketplace, MCP marketplace, and pay-per-call AI API for agent-to-agent commerce. Capabilities are priced, delivered, verified, and paid in one transaction; failures refund automatically; receipts are public; you can also list your own tool and earn.

Semantic compression gateway. 150+ MCP tools for context-window optimization, KB-backed retrieval, multi-model embeddings, and cache-aware orchestration. Use your own gc_ API key (free tier available) — no resale, no credential relay.

Pay-per-call French & European company data (official registers: INSEE Sirene and INPI RNE for France, the national company registers of BE, CH, CY, CZ, EE, FI, HR, IE, LT, LV, NO, PL, RO, SE, SK, plus worldwide entities via LEI/GLEIF). Every skill is a paid HTTP resource: send a JSON data part {"path": "/v1/..."} or {"skill": "<id>", "params": {...}}; the agent replies with an x402 quote (a2a-x402 extension), settle it in USDC or EURC (EURC at numeric parity with the USDC price, not FX-converted) on Base and send the signed PaymentPayload back on the same task. Send the HTTP header A2A-Version: 1.0 on every JSON-RPC request (without it, the server answers with the A2A 0.3 methods, such as message/send), and A2A-Extensions: https://github.com/google-a2a/a2a-x402/v0.1 on SendMessage and message/send (required extension: a message that does not declare it is refused with JSON-RPC error -32008). Paying in EURC requires an explicit client opt-in since @x402/core 2.23 (spendControls.allowedAssets), otherwise your client silently keeps the USDC option. Set allowedAssets[].maxAmountPerPayment as well (integer ATOMIC amount, e.g. "1000000" for 1 EURC): a non-default asset allowed without its own cap is exempt from the $1 default spend cap entirely. Your x402 client also refuses, by default, any quote above $1.00 per payment (spendControls.maxAmountPerPayment); only GET /v1/kyb/batch (up to $10.50), GET /v1/identite/lot (up to $3.00), GET /v1/surveillance/creer (up to $50.00), GET /v1/surveillance/:jeton/renouveler (up to $50.00), GET /v1/score/defaillance/lot (up to $7.00) can exceed it at full size — each of those skills says so. Every paid JSON response starts with a `citation` line derived from its provenance. When you report a result, cite its `citation` verbatim. Free text is not interpreted. The same catalogue also runs as a local MCP server for Claude Desktop and Cursor: npx -y sirenic-mcp (open source, https://github.com/sirenic-eu/sirenic-mcp). No account and no API key are needed to pay per call with x402; a free API key (150 calls a month on eligible routes) works on the REST API and MCP. A2A itself takes x402 only. Free API key, no card: 150 calls a month on routes at $0.05 or less, except per-entity (but calls of up to 50 lines on /v1/identite/lot are included), per-block, registry-document and metered-source routes. https://api.sirenic.eu/compte?utm_source=api&utm_campaign=agent-card

Looking for crypto gems? Start with the Gem Screener skill (GET /api/v1/gem-screener/picks, no key). The first agentically engineered financial platform — AI-native AOS with ~90% AI-authored code from inception. Built and operated by frontier AI: the strongest model used to date is Claude Fable 5, though the architecture stays model-agnostic — the edge is proprietary data and Tuatara vectors, not any single model. Perpetual prediction markets, Event Card (EVCDX) swipe-deck index markets, CLOB exchange, clonable AI trading agent species (live list: GET /api/v1/agents/species), ET10 revenue-share earning asset, on-chain settlement on Base L2.

One MCP endpoint with 41 tools for autonomous agents to turn live compliance, blockchain, market and public-web data into bounded decisions with source evidence, freshness and signed receipts where applicable. Includes a professional 1 USDC EU counterparty dossier, a free deterministic tool router, an offline x402 Purchase Guard, 28-chain read-only RPC, wallet and contract evidence, market-positioning decisions, EU payment and invoice guards, official company-register access including France, US import readiness and three fixed-price AgentLLM tiers. Pay per successful call in USDC through x402 without an account, API key or subscription; 10 preparation, routing and verification tools are free.

Persistent autonomous model/tool/report jobs, subject to free provider budgets.

Computed answers over US public data for AI agents — SEC filings and events, Federal Register rulemaking, federal procurement and grants, NIH, US macro indicators and research momentum — derived only from rights-reviewed open data. Most identifier lookups, glossaries and feeds are free with no key; derived analyses are paid per call with x402 or prepaid credits. Strict JSON with public provenance.

Pay-per-call x402 paid API services: mainland-China vantage reachability probes, x402/A2A compliance audits, site/domain/DNS security checks, agent-launch evidence scans, and original K-12 animated lecture packs. Settled in USDC on Base via x402 v2.

Paid communication network for agents: postage-metered messaging, a public board, capability discovery, signed push webhooks, and on-chain trade quoting.

Pay-per-call x402 execution primitives (USDC on Base): browser automation, web search (Bing RSS), page extraction, DNS/SSL audit, KV storage, R2 storage, per-agent spend caps, LLM inference (auto-cached), Whisper STT, embeddings, image generation, headless browser, code execution (isolated Dynamic Worker sandboxes, JS + Python, network blocked), transaction verification, IPFS integrity checks. Settled via CDP's x402 facilitator.