Most MCP servers you find in directories want an API key, a local install, or both. I wanted the opposite for a few boring-but-useful lookups my agents do all day: read a web page as Markdown, check a domain, look up CVEs for a package version, search papers. So I put 8 of them behind one remote MCP URL that works without a key.

https://2-29-135-242.sslip.io/mcp

It is a streamable-HTTP MCP server, stateless JSON, read-only tools. Each IP gets 25 free calls per UTC day. Above that, every tool is also available as a pay-per-call x402 endpoint (USDC), charged only when it returns results.

The 8 tools

Tool Source Typical use
web_read the page itself URL to clean Markdown for RAG or summaries
domain_intel RDAP + DNS + TLS registrar, expiry, nameservers, MX, SPF/DMARC, cert expiry
email_auth DNS SPF / DKIM / DMARC / MX check before cold email or vendor review
osv_vulns OSV.dev + CISA KEV + EPSS known vulns for package@version, fixed versions, exploit odds
literature_search OpenAlex + Crossref papers, DOIs, citations, open-access links
federal_register federalregister.gov US final/proposed rules and notices
clinical_trials ClinicalTrials.gov v2 trials by condition, drug, sponsor, status
prediction_markets Polymarket + Kalshi live odds for an event in one call

All sources are official or open APIs. No logins and no scraping behind walls.

Connect it

Claude Code

claude mcp add --transport http radar-tools https://2-29-135-242.sslip.io/mcp

Claude Desktop / Cursor / Windsurf (mcpServers JSON)

{ "mcpServers": { "radar-tools": { "url": "https://2-29-135-242.sslip.io/mcp" } } }

It is also in the official MCP Registry as io.sslip.2-29-135-242/radar-agent-tools, so registry-aware clients can find it by name.

Raw call with curl

MCP is just JSON-RPC over HTTP, so you can test it without any client:

curl -s https://2-29-135-242.sslip.io/mcp \ -H 'content-type: application/json' \ -H 'accept: application/json, text/event-stream' \ -d '{"jsonrpc":"2.0","id":1,"method":"tools/call", "params":{"name":"osv_vulns", "arguments":{"package":"requests","ecosystem":"PyPI","version":"2.25.0"}}}'

Real output (trimmed), run on 2026-11-06:

{"count": 8, "items": [{ "id": "GHSA-j8r2-6x86-q33q", "cves": ["CVE-2023-32681"], "summary": "Unintended leak of Proxy-Authorization header in requests", "severity": "MODERATE", "fixedVersions": ["2.31.0"], "knownExploited": false, "epss": 0.02974, "upgradeToFixAll": "2.33.0", "upgradeVerified": true }, ...]}

The part I use most is upgradeToFixAll: one version that fixes every listed advisory, re-checked on OSV so the suggested version itself has no known advisories. So an agent can open a single upgrade PR instead of reasoning about 8 advisories.

domain_intel on dev.to returns RDAP + DNS in one call (trimmed):

{"domain": "dev.to", "rdap": {"registrar": "Tonic", "created": "2016-04-05T02:27:16.000Z", "expires": "2027-04-05T02:27:16.000Z", "nameservers": ["jill.ns.cloudflare.com", "josh.ns.cloudflare.com"]}, "dns": {"MX": ["1 smtp.google.com."], "DMARC": ["v=DMARC1; p=reject; sp=reject; pct=100; ..."]}}

Prompts that work well

  • "Check requests==2.25.0 and urllib3==1.26.4 for known vulnerabilities and tell me the smallest safe upgrade."
  • "Read https://example.com/pricing and summarise the plans as a table."
  • "When does the domain of this vendor expire, and is their email protected by DMARC?"
  • "Find 5 recent papers on retrieval-augmented generation evaluation with DOIs."
  • "What are the current odds on Polymarket and Kalshi for the next Fed rate decision?"

Limits, honestly

  • 25 free calls per IP per day, 1,500 free calls per day in total (it is one small server).
  • Read-only. No browser rendering for heavy JavaScript apps in web_read; it fetches the HTML and extracts the main content.
  • Paid use is x402 (USDC on Base) at https://2-29-135-242.sslip.io/x402/<tool>. If you would rather pay per result with a normal account, the bigger versions run as Apify Actors under martin10291.

If a tool is missing a field you need, leave a comment with the call you made and what you expected. I read them.