@melis-ai/x402-tools-mcp

Boring infrastructure for agent builders. 22 pay-per-call utility tools served as an MCP server — scrape, validate, embed, store, moderate, notify, convert, prevent loops. No accounts, no API keys, no subscriptions. Pay with USDC on Base via the x402 protocol.

npx @melis-ai/x402-tools-mcp

→ Full catalogue with prices and live examples: agents.melis.ai → Canonical 5-step RAG pipeline: agents.melis.ai/pipelines/rag → 5-minute getting started: agents.melis.ai/docs/getting-started

Tool catalogue (22)

| Tool | Price (USDC) | Description | |------|-------------|-------------| | list_services | free | Returns the full catalogue with prices and endpoint URLs | | cacheserve | $0.001 | Fetch a URL with server-side caching — avoids redundant origin hits | | docconvert_text | $0.001 | Format conversion: md↔html, json↔csv, html→txt, etc. | | intentflow | $0.001 | Context handoff relay for multi-agent delegation (async, returns retrieve_url) | | memoryserve_write | $0.001 | Store text + embedding in Qdrant + SQLite, namespaced per agent_id | | memoryserve_query | $0.001 | Recall most-similar memories by semantic query | | memscrub | $0.001 | Scan retrieved RAG content for indirect prompt injection (10 patterns) | | notifyrelay_webhook | $0.001 | POST a JSON payload to a URL with optional HMAC-SHA256 signing | | schemagate | $0.001 | Validate a JSON response against a JSON Schema, return a hint on failure | | loopwall_hop | $0.0005 | Validate one hop of a signed multi-agent chain (loop / budget enforcement) | | loopwall_issue | $0.001 | Issue a signed Job Envelope at chain start with budget + hop cap | | imageguard | $0.002 | NSFW image classification (multi-class moderation on roadmap) | | notifyrelay_telegram | $0.002 | Send a Telegram message to a known chat ID | | promptguard | $0.002 | Score untrusted input for prompt injection risk (0–100) | | structextract | $0.002 | Extract structured JSON from HTML — tables, links, emails, phones | | xaudit | $0.002 | Validate API response content with a cryptographically signed certificate | | docconvert_pdf | $0.005 | Convert HTML or markdown to PDF (base64 output) | | kyaoracle | $0.005 | On-chain trust score (0–100) for an Ethereum/Base wallet address | | linkrisk | $0.005 | URL risk profile — heuristic phishing signals, redirect tracing | | markdownopt | $0.005 | Convert URL or HTML to clean LLM-ready markdown (~70% token reduction) | | notifyrelay_email | $0.005 | Send a transactional email via Resend (allowlisted, rate-limited) | | embedpay | $0.00005 / 1k tokens | OpenAI text-embedding-3-small wrapper, batch tier available | | linksafe | $0.01 | Definitive URL safety check via Playwright sandbox + VirusTotal | | scrapepay | $0.01 | Web extraction via Playwright (robots.txt enforced, SSRF-safe) | | pdf_render | $0.49 | High-fidelity URL or HTML → PDF via Playwright |

22 services. Live prices and live wallet on Basescan.

Why x402, why pay-per-call

• No signup tax. Every tool here works the moment your wallet has USDC. No accounts to provision, no API keys to rotate, no subscription tiers to forecast.
• Charge-on-success-only. Every service settles payment only on HTTP 2xx with non-empty content. Failed calls cost nothing — your retry budget is preserved.
• Composes naturally. ScrapePay → MarkdownOpt → EmbedPay → MemoryServe → MEMSCRUB is the canonical RAG pipeline. Each step's payment is independent and verifiable on-chain.
• MCP-native. One install, all 22 tools appear in Claude Desktop, Cursor, Cline, Continue, Claude Code, or any MCP-aware agent runtime.
• No vendor lock-in. x402 is a Linux Foundation protocol (April 2026) co-signed by Google, AWS, Stripe, Visa, Mastercard. Other providers will offer x402 services; your wallet client works with all of them.

Installation — Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "x402-tools": {
      "command": "npx",
      "args": ["@melis-ai/x402-tools-mcp"]
    }
  }
}

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json Windows: %APPDATA%\Claude\claude_desktop_config.json

Restart Claude Desktop. All 22 tools appear in the tool picker.

Installation — Cursor, Cline, Continue, Claude Code

See agents.melis.ai/docs/install-mcp for per-client setup.

Example: canonical RAG pipeline

// All 22 tools registered as MCP tools — your agent calls them like any function
const page    = await callTool('scrapepay',   { url: 'https://example.com/article' });
const md      = await callTool('markdownopt', { html: page.content });
const vec     = await callTool('embedpay',    { input: md.markdown });
const stored  = await callTool('memoryserve_write', {
  agent_id: 'agent-1', content: md.markdown, vector: vec.embedding,
});

// Later — recall and guard against indirect injection
const hits    = await callTool('memoryserve_query', {
  agent_id: 'agent-1', query: 'what did we learn about X?',
});
for (const chunk of hits.matches) {
  const scrub = await callTool('memscrub', { content: chunk.content });
  if (scrub.risk_level === 'safe') useChunk(chunk);
}

Total cost per 5k-token page: ~$0.017 USDC. Detailed walkthrough: agents.melis.ai/pipelines/rag.

Funding the wallet

x402 settles in USDC on Base (Coinbase L2). Two paths:

• Coinbase Wallet — buy USDC, switch to Base network, send to your agent's wallet.
• Bridge from Ethereum mainnet — bridge.base.org.

$1.00 of USDC covers 100 ScrapePay calls, 200 PromptGuard calls, or one full RAG-pipeline ingestion run.

Discovery surfaces (for agent builders + AI consumers)

| URL | Purpose | |-----|---------| | agents.melis.ai/llms.txt | Concise LLM-readable catalogue | | agents.melis.ai/llms-full.txt | Full schemas + composition recipes | | agents.melis.ai/openapi.json | OpenAPI 3.1 spec for all 22 endpoints | | agents.melis.ai/ai-plugin.json | ChatGPT-plugin manifest | | https://<service>.melis.ai/.well-known/mcp.json | Per-service MCP discovery | | agents.melis.ai/agents-faq | Agent-builder FAQ (distinct from human FAQ) |

Comparisons

• ScrapePay vs Firecrawl
• EmbedPay vs OpenAI Embeddings (direct)
• MemoryServe vs Pinecone
• Full alternatives doc

Source & licensing

• MCP wrapper source (this repo): MIT licensed.
• Service code (the 22 services themselves): closed source for security.
• Site content (agents.melis.ai docs): CC-BY-4.0 — attribute "melis x402 Tools" with a link to agents.melis.ai.

Security

Found a vulnerability? See SECURITY.md. Email [email protected]. Critical issues acknowledged within 24 hours.

Citing this work

If you use melis x402 Tools in research or downstream products, see CITATION.cff for the canonical citation.

Author

Sean Melis — agent operator and builder, London UK. Catalogue: agents.melis.ai · Email: [email protected]