Production-grade blockchain infrastructure for AI agents. 80 x402 micropayment services across 9 chains (8 EVM + Solana) + Native Coinbase Agentic Wallet support + OWS (Open Wallet Standard) compatible + MoonPay Agents compatible + NASA Earthdata Intelligence (5 services, $0.25/call) + ESA Satellite Data + AI Inference Gateway (GPT-4o-mini, $0.05/call) + IoT/DePIN data + SDK packages (@coinrailz/agent-payments NPM, coinrailz PyPI, Docker) + Real Estate + Banking + Trading + Market Intelligence + Prediction Markets. Processing fee: 1.5% + $0.01 per transaction.

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.

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

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.

Autonomous AI API engine. Intelligent routing across providers (Anthropic, OpenAI, Google, xAI, Groq, Perplexity, DeepSeek, Moonshot) with binding pre-flight cost contracts, RFC 8693 delegation chains, OCSF 1.3.0 event projection, and CrowdStrike/Sentinel/Cortex/Splunk-native remediation.

Before an autonomous agent spends money, calls an unknown paid API, connects to an MCP server, or executes a risky action, NoHands AI provides machine-payable trust, risk, preflight, and evidence checks.

Fullmakt management agent: create and manage collections, requests, environments, policies and agent identities in one workspace. Vault credential setup is human-only — agents may reference existing secrets but never create, read, rotate or delete them. Execution (calling a collection's requests as tools) happens over MCP at https://fullmakt.ai/mcp/{collection} with an execution-scoped token from the same token endpoint.

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

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

HALOWERK identwerk. 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.

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.

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).

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.

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.

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.

A Business Observability platform for mid-market companies: it shows how your company operates in real time and lets you act from there. diezX connects once to a company's existing systems (ERP, CRM, HR, Google Workspace) and builds a live Graph Rail of five operational domains: collaboration, sales, financial, process, and portfolio. On top of that graph, four A2A 0.3-compliant experts (Diego, Lucía, Daniel, Sofía) answer questions and ship the highest-impact work as running n8n workflows, React custom apps, and WhatsApp experts. Each expert queries its domain graph before answering. Hosted on Google Cloud (Cloud Run) with inference on Vertex AI. Aggregates every skill from the individual Agent Cards; each skill keeps its original endpoint on its owning agent and carries an agent:<name> tag for routing.

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.

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.

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.

402 is the answer. The Oracle is how you ask. Paid x402 oracle on Base: answers questions, diagnoses HTTP 402 challenges, reviews MCP servers, rewrites Bazaar listings and completes oracle tasks. USDC on eip155:8453, payTo 0x0d25a44f74868ece53b305c97139cf4b62963410. Free: /api/health, /api/pricing. Catalog: https://x402orcle.vercel.app/.well-known/x402.

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

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.

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.

Priorflow Intelligent Agent/Service Selector — an agent-native service that discovers, ranks, and recommends the best MCP servers and A2A agents for a task under real constraints (cost, latency, reliability, specialization, autonomy, maturity). Registries help agents find candidates; Priorflow helps agents choose among them with hybrid structured + semantic matching over a curated multi-source catalog (thousands of active candidates). Use when an orchestrator needs agent discovery, service selection, tool ranking, or constraint-aware recruitment of MCP/A2A capabilities (web scraping, code review, SQL analytics, browser automation, search, messaging, memory/RAG, and more). Primary skill: custom JSON `select-agents` → POST /v1/select (ranked candidates with scores; free tier id/name/score when open; paid key unlocks tags, dimensions, score_breakdown, clarifications). Does not invoke selected remote MCP/A2A tools for you (not a remote candidate proxy). This host is NOT an MCP server (MCP adapter off). Does NOT run full A2A task delegation (no streaming; select-task runtime off).

Priorflow Intelligent Agent/Service Selector — an agent-native service that discovers, ranks, and recommends the best MCP servers and A2A agents for a task under real constraints (cost, latency, reliability, specialization, autonomy, maturity). Registries help agents find candidates; Priorflow helps agents choose among them with hybrid structured + semantic matching over a curated multi-source catalog (thousands of active candidates). Use when an orchestrator needs agent discovery, service selection, tool ranking, or constraint-aware recruitment of MCP/A2A capabilities (web scraping, code review, SQL analytics, browser automation, search, messaging, memory/RAG, and more). Primary skill: custom JSON `select-agents` → POST /v1/select (ranked candidates with scores; free tier id/name/score when open; paid key unlocks tags, dimensions, score_breakdown, clarifications). Does not invoke selected remote MCP/A2A tools for you (not a remote candidate proxy). This host is NOT an MCP server (MCP adapter off). Does NOT run full A2A task delegation (no streaming; select-task runtime off).

Monitor backups, automations and scheduled tasks. Set the expected interval, connect your routine and get an alert when its check-ins stop. Ten monitors are free.

AI-native trade business management for Australian trades. 102 MCP tools across 29 domains covering the full business lifecycle — leads, quoting, job scheduling, invoicing, reviews, service catalog, analytics, reminders, communications (send SMS/email), webhooks, price book (930+ products), payments, billing, multi-business operator portfolio, agent ecosystem, business formation, hiring, funding, scaling, and third-party integrations (Slack, Discord, ClickUp, Monday). The only trade platform with native MCP support.

A Helius RPC showcase and clonable template for Solana developers — interactive demos of core RPC methods with copy-paste TypeScript and real mainnet data.

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.

Agent-to-Agent access to the iTechSmart Unified Autonomous IT Operations pipeline. Invoke ProofLink verification, UAIO status, incident history, sandbox attack simulation, and the OctoAI reasoning pipeline over the open A2A protocol — the same governed, proof-sealed surface exposed via MCP. Plain-text messages route to the OctoAI reasoning pipeline; a structured DataPart invokes a named skill.