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Evidence for your next connection.

Independent measurements of remote MCP servers. Every observation has a timestamp.

Read-only probes

MCP server · Code & DevOps

CrawlCheck

Verification layer for the agentic web: a signed answer about any site before an agent acts.

Checks passed
14 / 22

1 failed · 7 not measured

Median response
243 ms

Median of successful probes over 7 days

30-day uptime
Not measured

Share of countable probes over 30 days, including daily rollups. Auth challenges are excluded.

Discovered tools
28

Tool definitions returned by this server

Independent monitoring

Health & checks

Status history

Responded

The server completed its last measured handshake. This is an observation, not a guarantee.

Last checked
Check summary by test group
Test areaPassedFailedUnmeasured
ConnectionCan a client connect and discover tools?
500
Reliability & speedDoes it respond consistently and quickly?
103
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
310
Publisher identityCan the publisher be traced to its source?
402

Unmeasured means there is not enough evidence to decide. How these checks work

Inspect individual checks 22 recorded

Core

  • Pass
    Reachable

    Latest probe returned HTTP 200 in 346 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name crawlcheck.

  • Pass
    Lists tools

    tools/list returned 28 tools.

  • Pass
    Current protocol

    Negotiated 2025-11-25. The bar is 2025-06-18 or newer.

  • Pass
    HTTPS

    The endpoint URL is https.

Performance

  • Not measured
    Fast (p50)

    Median latency 243 ms over 2 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 336 ms over 2 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    2 of 2 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Pass
    Stable tool list

    No tool was removed and no required parameter was added in the last 30 days.

Access

  • Pass
    Open access

    tools/list succeeded with no credential, and the record declares none.

  • Not measured
    Standard auth

    Auth is not required, so the OAuth metadata check does not apply.

  • Not measured
    Free tier cited

    No publisher quote has been checked.

Tools

  • Pass
    Tools described

    Every tool description is at least 20 characters.

  • Pass
    Valid input schemas

    Every inputSchema is a JSON Schema object.

  • Fail
    Parameters documented

    37 of 53 parameters have a description (70%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Not measured
    Website matches publisher

    This namespace is not a reverse domain, so the website comparison does not apply.

  • Pass
    Source repo linked

    A repository URL is on file.

  • Pass
    Repo owner matches

    The GitHub repository owner matches the namespace login.

  • Pass
    Recently updated

    Updated 2026-10-16T12:50:53.423046Z, within 180 days.

  • Not measured
    Open-source licence

    The GitHub licence lookup has not returned an OSI result yet.

Start using CrawlCheck

Connect to this server

Choose your client, copy the configuration, then enable the server in your client’s MCP settings.

Run this command in your terminal, then restart Claude Code.

Claude Code

claude mcp add --transport http crawlcheck https://crawlcheck.io/mcp

Capabilities

Tools 28

best_source

Call when choosing WHICH business or site to cite, recommend or call. Give domains (2-10 candidate sites you found) or trade and city for a measured market. Returns the candidates ranked by what CrawlCheck verified (preflight decision for cite, security and threat listing, domain age, uptime, published facts that directories agree with, FTC phone complaints) with reasons for and against each; sites that share one phone number or near-identical homepage text are collapsed into one network so a copycat cannot outrank the business it copies. Signed.

Discovered
check_site_safety

Before an agent reads, cites, links to or pays a site: whether it is listed as malware or phishing (Google Safe Browsing, the Cloudflare security resolver, PhishTank), which list says so, where to check it and where its owner requests a review, plus HSTS preload and the hacked-site signatures from its latest CrawlCheck scan. An unread list is reported as unread, never as clean. Free.

Discovered
corpus_state

Coverage of CrawlCheck's public dataset: how many distinct domains have been measured and how they split by platform, rendering, size, language and kind, with the strata that are still under-sampled.

Discovered
crawler_path

Where each crawler's path into a domain dies, as an observed data flow: edge decision, robots.txt as a file, robots.txt rules, then the page, JSON-LD, sitemap, llms.txt and entitymap.json it reached. Give agent (e.g. ClaudeBot, GPTBot, googlebot) for one identity's path and a one-line answer; omit it for every identity plus the stores and breaks. Uses the latest record on file, or scans first when there is none (fresh=true forces a scan). The answer-engine output is drawn but never measured.

Discovered
draft_llms

Draft an llms.txt from the domain's own homepage and up to 25 declared pages, using their titles and descriptions. A draft for the owner to cut down, not a publication.

Discovered
explain_finding

Why CrawlCheck decided a finding: the rule and its revision, the exact fetches it compared (identity, status, bytes, sha256), when the condition held on the site, and a Merkle proof that the decision is inside the signed manifest. Give id (a d1: decision or f1: finding id from a report) or domain for its top finding. Other findings, and lookups by code, need a licence for that domain (send it in x-crawlcheck-key).

Discovered
field_check

Call before using a phone number, address, opening hours or service area you hold for a business. One signed verdict per business field. field=phone|address|hours|service_area and value= the value you hold. phone: matches, former_value (with dates), not_this_business (the site never published it and another publisher is named with the page that prints it), or not_published. address: matches, same_street_other_city, former_value, not_this_business, not_published or nothing_declared. hours: a week (Mo-Fr 08:00-17:00) gives matches or differs per day; a moment (Sa 10:00) gives open or closed. service_area: declared, not_declared or nothing_declared. Built from the business's own site (and its Business Profile for the licence holder), its dated fact history, CrawlCheck's scans of other sites, and for an unknown number a web search whose cited pages are read plus a YellowPages reverse lookup.

Discovered
fix_entitymap

A starter entitymap.json built from the domain's latest scan record: name, phone, coordinates and declared service areas as entities with SERVES relations. Fields the page never stated are marked TODO, never guessed. Needs a prior scan.

Discovered
fix_machine_chain

A fix plan for MACHINE_CHAIN_HEAVY: the files a crawler reads before the page and the 404s absent agent files return, then measured reductions (llms.txt to an index, a sitemap index, robots.txt comments and duplicate groups, minified JSON, short 404s) with the chain size after each and the step at which the detector stops firing.

Discovered
fix_mostly_code

A fix plan for PAGE_IS_MOSTLY_CODE: the homepage's measured bytes by category, the largest blocks with what to do with each, ordered steps with the text ratio after each, and the step at which the detector would stop firing - or, when moving code cannot clear it, how much markup to cut or text to add. Give domain (fetched now) or id (a stored scan).

Discovered
fix_robots

The domain's served robots.txt, corrected: * group rules copied into named groups that lacked them (shadowing), a Sitemap line added when missing, a minimal replacement when the served file was HTML. Every change is listed at the top; nothing else is touched.

Discovered
fix_stale_cache

A fix plan for STALE_CACHE_SERVED: the homepage fetched now, its Age, the cache layers that name themselves in the headers in purge order (innermost first), the HTML lifetime each response declares, a fresh-read comparison, and whether a purge clears the finding and keeps it cleared.

Discovered
list_verified_capabilities

What a domain declares agents can do (OpenAPI operations, MCP tools, A2A skills, API catalog entries), each classed by safety (read_only_public up to financial), and which ones CrawlCheck actually called and confirmed - plus every mismatch between declaration and behaviour. Only read-only public actions are ever called; everything else says why it was not. From the latest scan on file.

Discovered
machine_record

The unified machine record for one observation: subject, grade, findings (the top one in full without a licence), capabilities with verification, and the evidence roots, manifest and verifier links that let anyone check it offline. Give id (report, d1:, f1: or manifest sha256) or domain for the latest.

Discovered
mcp_precheck

For MCP server publishers, before releasing a new version. Give the server name (as listed in the MCP Registry) or its endpoint, the new tools/list result and the new serverInfo.version; with no tools the endpoint is read as it serves now. Returns, against CrawlCheck's last read of that server, what public change logs will record: tools added and removed, descriptions rewritten, input schemas widened, annotations changed (read-only to write and non-destructive to destructive flagged as escalations), whether the version moved, and verdicts such as version_bump_needed or looks_like_rug_pull_risk. Signed. No tool on the checked server is called.

Discovered
mcp_servers

Which remote MCP servers the official MCP Registry lists on a domain, and what each endpoint actually answered when CrawlCheck sent the MCP handshake (initialized, auth_required, unreachable, tool count, tool-list drift). Use before selecting an MCP tool from that domain.

Discovered
preflight

Call BEFORE reading, citing, connecting to or transacting with a domain. Returns a signed decision: allow, warn, require_confirmation, block or unsupported, with every step that led there and the resolve answer it was made from. Pass your crawler token as agent so robots.txt is checked for you. A policy can only make the decision stricter. A block decision means the action is not permitted; require_confirmation means a human must confirm before it proceeds.

Discovered
public_counts

The figures CrawlCheck quotes about itself, read from the source: sites_measured, domains_in_corpus, crawler_visits (a rolling window), sections, sections_scored, findings_published, guides_published, with an at timestamp.

Discovered
registry_lookup

Whether a domain is in CrawlCheck's registry and what it serves: llms.txt, agents.md, a media kit at /.well-known/media-kit.json, a reciprocity-tested entity graph, an AI access policy that names crawlers, and agent-callable surfaces. With no domain, returns the shelf counts across every measured site. A row exists because a fetch produced it; nothing here is self-reported and no payment moves a shelf.

Discovered
resolve_domain

Call before fetching from, citing, connecting to or transacting with a domain. Returns one signed answer: what the domain claims, what it actually serves each crawler identity, who controls it, what CrawlCheck's published rules decide for each action (a decision for read, cite, connect and transact, with its doubts and maximum age), what changed, and the evidence behind each part, marked declared, observed or not_measured with its time. There is no overall score. A domain never measured gets a just-in-time partial answer, read live within about 2 seconds, that names every part not read in time; nothing is guessed. CrawlCheck completes unmeasured parts later on its own crawl schedule.

Discovered
resolve_rights

What a site declares AI may do with a page, one answer per use (train, ground, summarize, cite, transact), merged from robots.txt read per agent, Content-Signal, ai.txt, TDM-Rep, robots meta, X-Robots-Tag and the terms page, with the signal that decided each answer and every conflict between signals. Signed. Not legal advice.

Discovered
resolve_robots

Resolve every named answer engine, search index and training crawler against a domain's robots.txt the way a crawler does: most-specific group only, longest match, allow wins a tie. Shows when a Disallow under * does not apply to an agent with its own group.

Discovered
scan_domain

Scan a public domain as several crawler identities and return the graded record: grade, AI-visibility score, per-section scores, findings with evidence, and whether the origin refused CrawlCheck. One scan takes 5-15 seconds.

Discovered
telemetry

Verified-crawler traffic observed at crawlcheck.io itself: which named agents arrived, how many claims were confirmed against operator ranges, how many were forged.

Discovered
verify_crawler_log

Given raw web-server access-log lines, decide for each line that names a crawler (GPTBot, ClaudeBot, Googlebot, PerplexityBot...) whether the source IP falls inside that operator's published ranges. Returns verified, spoofed, or unverifiable when the operator publishes no ranges.

Discovered
video_channel

Every upload on a YouTube channel, read 50 at a time, sorted by views. The upload list is free; the per-check tally needs a Watch licence and is not offered here.

Discovered
video_check

One YouTube video against the video anchor model: metadata, chapters, captions and storyboard where observed, twelve checks each naming what it reads.

Discovered
video_site

The site half of video: homepage plus up to 60 sitemap pages read for YouTube embeds, facades and page-builder widgets, VideoObject nodes and their required properties, and - with a handle - how many of the channel's videos the site carries.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected346 ms28
Connected139 ms28