Official MCP RegistryListed
x402 Web Tools
Web/PDF to Markdown, transcription, paper search and citation checks. Pay per call in USDC via x402.
First seen 20 Oct 2026. Evidence as of 21 Oct 2026.
9
Tools
From an anonymous probe
1
Source listings
Each with its own history
6
Recorded changes
Since first seen
Tools
| Tool | Description | Behaviour |
|---|---|---|
| check_citation | Check whether a cited paper really exists (catch hallucinated or mistyped references) and whether it has been retracted. Give a doi, or a title with optional year and first_author. Returns exists, verdict (verified | found | doi_exists_metadata_mismatch | uncertain | not_found), confidence (high/medium/low) with a note on what matched, is_retracted (OpenAlex is_retracted + Crossref/Retraction Watch notices) and the best match. Data: OpenAlex (CC0, openalex.org) with Crossref REST (crossref.org) for retraction notices and as fallback. Upstream errors are not charged. Costs $0.002 USDC per check via x402. | Not declared |
| get_paper | Look up one scholarly work by DOI (10.xxxx/..., doi.org URL), arXiv id (arXiv:1706.03762) or OpenAlex work id (W...). Returns title, authors, year, venue, DOI, citation count, references count, open-access PDF link, abstract, OpenAlex id and a retraction flag (OpenAlex is_retracted plus Crossref/Retraction Watch notices). Data: OpenAlex (CC0, openalex.org) with Crossref REST (crossref.org) for retraction notices and as fallback. Not-found and upstream errors are not charged. Costs $0.002 USDC per lookup via x402. | Not declared |
| health | Free health check. Returns service status, version, tool prices, network and the plain-HTTP x402 endpoints. | Not declared |
| ping | Paid connectivity test: returns ok and a server timestamp. Use it to check that your x402 payment flow works end to end. Costs $0.001 USDC per call via x402. | Not declared |
| read_pdf | Fetch a public PDF (max 10 MB) and convert it to Markdown with Cloudflare Workers AI toMarkdown. Returns title (if detected), url, markdown, word_count. Same URL safety rules as read_url. Failed conversions are not charged. Costs $0.006 USDC per call via x402. | Not declared |
| read_url | Fetch a public web page and return its main content as clean Markdown (readability extraction): title, url, final_url, markdown, word_count. HTML, plain text, Markdown, JSON and XML. Static fetch only (no JavaScript rendering). Respects robots.txt, blocks private/loopback/metadata hosts, max 3 MB / 15 s, no logins or paywall bypass. For PDFs use read_pdf. Failed reads are not charged. Costs $0.002 USDC per call via x402. | Not declared |
| read_url_safe | Same as read_url plus a heuristic prompt-injection check: flags hidden/invisible text, instruction-like phrases ("ignore previous instructions", role reassignment, secret exfiltration, chat-template tokens), suspicious HTML comments and zero-width/Unicode-tag characters. Returns injection_check {flagged, risk none|low|medium|high, signals}. Heuristic, not a guarantee. Failed reads are not charged. Costs $0.003 USDC per call via x402. | Not declared |
| search_papers | Search scholarly papers (OpenAlex index of 250M+ works). Returns up to 25 results with title, authors, year, venue, DOI, citation count, open-access PDF link, abstract (reconstructed from OpenAlex's inverted index; may be null when the publisher withholds it) and OpenAlex id. Optional from_year / to_year / open_access_only filters. Data: OpenAlex (CC0, openalex.org) with Crossref REST (crossref.org) for retraction notices and as fallback. Upstream errors are not charged. Costs $0.005 USDC per search via x402. | Not declared |
| transcribe_audio | Transcribe a public direct audio file URL (mp3, wav, m4a, ogg/opus, flac; max 25 MB and 10 minutes, checked from the file header before transcription) with Whisper (@cf/openai/whisper-large-v3-turbo) on Cloudflare Workers AI. Returns text, language, duration, segments with timestamps, optional SRT/VTT subtitles. YouTube/TikTok/Instagram and other page URLs are rejected. Failed transcriptions and files with no detected speech are not charged. Costs $0.01 USDC per file via x402. | Not declared |
Change history
- search_papers: tool added
- health: description changed (+"version," +"prices, network" +"the plain-HTTP x402 endpoints.")
- get_paper: tool added
- check_citation: tool added
- Description changed (registry)
- Listed (registry)
| Source | Listing | First seen | Last seen | Versions |
|---|---|---|---|---|
| Official MCP Registry | dev.workers.microtools-x402.x402-web-tools/web-tools | 20 Oct 2026 | 21 Oct 2026 | 2 |