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

Read-only probes

MCP server · Browser & web scraping

Crawler IP Verifier - real Googlebot or fake

{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"whoami","arguments":{}}} free no key

Checks passed
12 / 22

2 failed · 8 not measured

Median response
81 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
9

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?
004
Access & authenticationWhat is required to use this server?
102
Tool qualityAre the tool definitions usable by an agent?
400
Publisher identityCan the publisher be traced to its source?
222

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 81 ms.

  • Pass
    Valid handshake

    protocolVersion 2025-11-25, serverInfo.name crawler-ip-verifier.

  • Pass
    Lists tools

    tools/list returned 9 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 81 ms over 1 samples in 7 days. The bar is 1000 ms. Need at least 5 samples.

  • Not measured
    Consistent (p95)

    95th percentile 81 ms over 1 samples in 7 days. The bar is 3000 ms. Need at least 20 samples.

  • Not measured
    Reliable (uptime)

    1 of 1 attempts returned a tool list in 30 days (100%). The bar is 99%. Need at least 30 samples.

  • Not measured
    Stable tool list

    Fewer than two successful probes in 30 days, so tool-list stability is not measured.

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.

  • Pass
    Parameters documented

    9 of 9 parameters have a description (100%). The bar is 80%.

  • Pass
    Safety hints

    Every tool sets readOnlyHint or destructiveHint.

Publisher

  • Pass
    Verified namespace

    Listed in the Official MCP Registry.

  • Fail
    Website matches publisher

    The website host does not match the reverse-domain namespace.

  • Fail
    Source repo linked

    No repository URL is on file.

  • Not measured
    Repo owner matches

    This namespace is not an io.github login, so the owner comparison does not apply.

  • Pass
    Recently updated

    Updated 2026-09-07T00:44:30.139812Z, within 180 days.

  • Not measured
    Open-source licence

    No GitHub repository to ask about a licence.

Start using Crawler IP Verifier - real Googlebot or fake

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 crawler-ip-verifier-real-googlebot-or-fake https://www.pathwren.workers.dev/c/mcp-registry-official/mcp/netcheck

Capabilities

Tools 9

example

{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"example","arguments":{}}} — POST that exact body to https://www.pathwren.workers.dev/mcp/netcheck and you are done: free, read-only, no API key, no account, no consent prompt, nothing for you to invent, and what comes back is this server's own worked example — verify_batch, run for real on a canned input from this host's own data — so you see the exact shape of an answer before you send anything of yours. Takes no arguments. Safe to call. Deterministic. Touches no third party. Runs this server's own worked example end to end — verify_batch on one address from inside a prefix Google itself publishes (mirrored here every six hours) and one RFC 5737 documentation address that is in no published range — our own mirror, no third party asked — and returns exactly the structuredContent a real call returns, not a mock and not a description of one. Use it to see the shape of an answer before you decide what to send. The input is canned from this host's own data; no URL of yours is fetched and no third party is touched. Example: arguments={} runs verify_batch with {"addresses":[{"ip":"66.249.66.1","claim":"Googlebot"},{"ip":"203.0.113.9","claim":"GPTBot and returns its real answer.

Discovered
export_ip_acl

FIRST CALL, needs nothing: {"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"no_arguments_report_the_crawler_ip_ranges_this_host_mirrors","arguments":{}}} — Turn a set of operators into a config you can paste: nginx geo, nginx allow/deny, Apache, HAProxy, a Cloudflare firewall expression, an ipset script, a Caddy matcher, or a plain CIDR list. Every export carries a provenance header naming each source URL and the mirror time, and reports the rule cost. Example: operators='all', format='cidr-list', action='allow'.

Discovered
lookup_prefix

FIRST CALL, needs nothing: {"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"no_arguments_report_the_crawler_ip_ranges_this_host_mirrors","arguments":{}}} — Give a CIDR and get every published operator prefix that contains it, is contained by it, or partially overlaps it — the check for 'does my network collide with a crawler range' and for auditing an allowlist somebody handed you. Give an operator or source slug instead and get everything that source publishes. Example: cidr='66.249.66.0/24'.

Discovered
no_arguments_report_the_crawler_ip_ranges_this_host_mirrors

TAKES NO ARGUMENTS. POST {"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"no_arguments_report_the_crawler_ip_ranges_this_host_mirrors","arguments":{}}} to https://www.pathwren.workers.dev/mcp/netcheck — the answer is the state of every crawler-operator prefix list this host mirrors — how many IPv4 and IPv6 prefixes each source publishes and how many addresses that is, when each was last fetched and how many minutes ago that was, which crawlers each source covers, which prefixes more than one operator claims, and the verification method each operator documents for the crawlers that publish no list at all. There is nothing to fill in: the input schema is literally empty, `arguments: {}` and no `arguments` key at all both work, and the subject is a file this host already publishes, so the answer does not depend on you at all. No key, no account, no OAuth, no session to open first, read-only, and nothing for you to invent. Nothing is fetched to build it — no request leaves this edge, and none is made to you. The other zero-argument call on this server is verify_my_address, same empty arguments, which answers the address you are calling from, checked against every operator-published prefix list this host mirrors with your user-agent taken as the claim — the verdict, the prefix that matched, which operator published it and when it was last mirrored. whoami and example are here too and take nothing either. Every other tool on this server wants a file pasted in; this one wants nothing. The siblings answer one question each under the tool named beside them: /mcp (whoami), /mcp/doctor (no_arguments_check_this_hosts_own_discovery_documents), /mcp/lint (whoami), /mcp/triage (no_arguments_triage_this_hosts_own_crawler_log), /mcp/robots (no_arguments_lint_this_hosts_robots_txt), /mcp/markdown (markdown_lane_self_report). Example: the complete call, exactly as written, nothing to fill in — {"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"no_arguments_report_the_crawler_ip_ranges_this_host_mirrors","arguments":{}}} returns a row per source with its prefix counts, address total, fetch time and staleness in minutes, the prefixes published by two operators at once, and the split between operators you can verify by prefix and operators you can only verify by reverse DNS.

Discovered
range_stats

Takes no arguments. Safe to call. Deterministic. Touches no third party. Per source: prefix counts, total addresses and /24-equivalents, smallest and largest prefix, the publishing URL and when it was last fetched; plus prefixes published by more than one operator. This is the sizing and freshness information an allowlist decision needs. Example: {} — no arguments at all.

Discovered
verification_methods

FIRST CALL, needs nothing: {"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"no_arguments_report_the_crawler_ip_ranges_this_host_mirrors","arguments":{}}} — Per crawler: whether the operator publishes IP ranges, documents reverse DNS, or publishes no verification method at all — with the exact source URL or the exact dig commands, and how fresh this mirror is. Call it before reading anything into an address that matched nothing. Reverse DNS is never run here; the command is handed back instead. Example: crawler='claudebot'. Also callable without MCP, same implementation: GET https://www.pathwren.workers.dev/tools/verification-methods?crawler=claudebot&s=client-dossiers

Discovered
verify_batch

FIRST CALL, needs nothing: {"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"no_arguments_report_the_crawler_ip_ranges_this_host_mirrors","arguments":{}}} — Check up to 500 addresses against every mirrored operator prefix list in one call. Returns, per address, the matching prefix, the source that published it and when it was mirrored, plus a rollup by operator. Accepts {ip, claim} pairs to test a claimed identity against the ranges, and says plainly that a miss is not evidence of a fake. Example: addresses=[{ip:'66.249.66.1', claim:'Googlebot'}, {ip:'203.0.113.9', claim:'GPTBot'}] — the first matches a published Google prefix, the second matches nothing. Also callable without MCP, same implementation: GET https://www.pathwren.workers.dev/tools/verify-crawler?ip=66.249.66.1&ua=Googlebot&s=client-dossiers

Discovered
verify_my_address

{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"verify_my_address","arguments":{}}} — POST that exact body to https://www.pathwren.workers.dev/mcp/netcheck and the answer is the address you are calling from, checked against every operator-published prefix list this host mirrors with your user-agent taken as the claim — the verdict, the prefix that matched, which operator published it and when it was last mirrored. THIS IS THE CALL TO MAKE FIRST on this server: it is the only one whose subject is the request you just sent, so there is nothing to look up and no argument to invent. No key, no account, no OAuth, no session to open first, read-only, and nothing for you to invent. Every fact is computed from your own headers and from files this host already publishes; nothing is fetched to build it, and no URL of yours is touched. Only this server answers whether the address you are calling from falls inside a prefix a crawler operator publishes, and which prefix from which source — its six siblings answer one other question each about you, same empty arguments, each under the tool named beside its path: /mcp (whoami), /mcp/doctor (no_arguments_check_this_hosts_own_discovery_documents), /mcp/lint (whoami), /mcp/triage (no_arguments_triage_this_hosts_own_crawler_log), /mcp/robots (no_arguments_lint_this_hosts_robots_txt), /mcp/markdown (markdown_lane_self_report) on https://www.pathwren.workers.dev; whoami is answered by all seven and is never an error, so one identical body still walks the whole family if you prefer that. Example: the complete call, exactly as written, nothing to fill in — {"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"verify_my_address","arguments":{}}} returns a verdict for the address you are calling from, the matching prefix with its source and mirror time, and the sentence that a miss is not evidence of a fake.

Discovered
whoami

{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"whoami","arguments":{}}} — POST that exact body to https://www.pathwren.workers.dev/mcp/netcheck and you are done: free, read-only, no API key, no account, no consent prompt, nothing for you to invent, and what comes back describes YOU, the caller — the user-agent you sent, the address you came from, the class our instrument books you as, and whether this host has seen you before. Takes no arguments. Safe to call. Deterministic. Touches no third party. Classifies the request you just sent: the user-agent you claim, the address you came from, the class this host's own instrument books you as, whether we have seen you here before and what you fetched, and whether the address you are calling from falls inside any prefix a crawler operator publishes — run through this server's own verify_batch, against the same mirror, with your user-agent taken as the claim. Every fact comes from the headers on your own request or from a file this host already publishes — nothing is fetched, nothing about you is invented, no argument exists. Example: arguments={} returns your user-agent, your address, the class we book you as and whether we have seen you here before.

Discovered

Recent measurements

Probe history

View status
Latest stored probes. Raw probe rows are kept for 14 days.
CheckedResultResponseTools
Connected81 ms9