Crawler IP Verifier vs Robots Policy Lint | AllMCPs
Side-by-Side Model Context Protocol Comparison
Crawler IP Verifier vs Robots Policy Lint
In-depth architectural comparison of the Crawler IP Verifier and Robots Policy Lint MCP servers. Compare execution transports, security boundaries, tool capabilities, quality scores, and ready-to-paste client installation snippets for Claude, Cursor, Windsurf, and VS Code.
At a Glance & Executive Verdict
Crawler IP Verifier
Developer Tools · Remote HTTP/SSE
Quality: 55/100 (Good) | Auth: No auth required
Robots Policy Lint
Developer Tools · Remote HTTP/SSE
Quality: 55/100 (Good) | Auth: No auth required
Verdict Summary: Choose Crawler IP Verifier if you need specialized Developer Tools tools running via a hosted cloud SSE transport. Choose Robots Policy Lint if your workspace requires Developer Tools integration with remote web transport. Both servers can be configured concurrently in your client's mcpServers manifest.
Which MCP Server Should You Choose?
C
Choose Crawler IP Verifier when:
You need dedicated capabilities in the Developer Tools domain.
You prefer remote streaming HTTP/SSE transport architecture.
Your security boundary fits: No auth required (Free / Open Source).
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.
Ready-to-Paste Client Configurations
Paste either (or both) of these JSON server blocks into your client config file (e.g. claude_desktop_config.json or ~/.cursor/mcp.json).
Crawler IP Verifier is categorized under Developer Tools and uses a remote streaming HTTP/SSE transport. In contrast, Robots Policy Lint belongs to Developer Tools using remote streaming HTTP/SSE transport. Select Crawler IP Verifier when you need capabilities focused on developer tools and Robots Policy Lint when you require tools for developer tools.
{"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.
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.
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.
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
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'.
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'.
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
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.
Robots Policy Lint Tools (9)
no_arguments_lint_this_hosts_robots_txt
TAKES NO ARGUMENTS. POST {"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"no_arguments_lint_this_hosts_robots_txt","arguments":{}}} to https://www.pathwren.workers.dev/mcp/robots — the answer is the full RFC 9309 lint of this host's OWN robots.txt and ai.txt, run for real on the bytes it serves — every finding with its severity, its line number and the fix, plus an allowed/disallowed verdict per crawler token per path with the exact rule and line that produced it, and the check that the two files still agree with each other. 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 am_i_allowed, same empty arguments, which answers what this host's own robots.txt says to YOU — the group that matches your user-agent, the line that decided it, that group verbatim, and whether you are allowed each of three paths, evaluated by the same RFC 9309 engine as check_path_allowed. 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/netcheck (no_arguments_report_the_crawler_ip_ranges_this_host_mirrors), /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_lint_this_hosts_robots_txt","arguments":{}}} returns both files parsed and linted, their findings with line numbers and fixes, a verdict table naming the rule that decided each row, the roll-up of which indexed AI crawlers this host's file actually stops, and the agreement check between robots.txt and ai.txt.
am_i_allowed
{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"am_i_allowed","arguments":{}}} — POST that exact body to https://www.pathwren.workers.dev/mcp/robots and the answer is what this host's own robots.txt says to YOU — the group that matches your user-agent, the line that decided it, that group verbatim, and whether you are allowed each of three paths, evaluated by the same RFC 9309 engine as check_path_allowed. 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 what this host's own robots.txt says to YOU — the group that matches your token, the line that decided it, and whether you are allowed the path you are on — 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/netcheck (no_arguments_report_the_crawler_ip_ranges_this_host_mirrors), /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":"am_i_allowed","arguments":{}}} returns your matched group and the line it was matched on, plus an allowed/disallowed verdict for /, /data/agents.json and /mcp/robots.
whoami
{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"whoami","arguments":{}}} — POST that to https://www.pathwren.workers.dev/mcp/robots and the answer is the user-agent you sent, the class this host's own instrument books it as, whether we have logged you here before — and the part only this server can answer: which group in this host's own robots.txt matches YOUR user-agent, the line that decided it, and whether you are allowed the paths you are on, evaluated by the same RFC 9309 engine as check_path_allowed. Takes no arguments. Safe to call. Deterministic. Touches no third party. Nothing is fetched to build it: every fact comes from the headers on your own request or from a file this host already publishes. Only this server answers the last part — its five 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/netcheck (no_arguments_report_the_crawler_ip_ranges_this_host_mirrors), /mcp/markdown (markdown_lane_self_report) on https://www.pathwren.workers.dev. Example: arguments={} returns your user-agent, your address, the class we book you as, whether we have seen you here before, and what this host's own robots.txt says to YOU — the group that matches your token, the line that decided it, and whether you are allowed the path you are on.
example
{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"example","arguments":{}}} — POST that exact body to https://www.pathwren.workers.dev/mcp/robots 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 — lint_robots_txt, 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 — lint_robots_txt on three groups lifted verbatim from this host's own published /robots/block-ai-training.txt and /robots.txt — our data, not yours, and nothing is fetched — 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 lint_robots_txt with {"robots_txt":"# lifted from https://www.pathwren.workers.dev/robots/block-ai-training.txt and returns its real answer.
lint_robots_txt
FIRST CALL, needs nothing: {"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"no_arguments_lint_this_hosts_robots_txt","arguments":{}}} — Parse a robots.txt you paste and report every fault that makes it do something other than what it looks like: misspelled directives, a full UA string where a product token belongs, rules before any User-agent line, duplicate groups, noindex (unsupported since 2019), relative Sitemap URLs, BOM. Each finding carries the line number and the fix. Example: robots_txt='User-agent: GPTBot\nDisallow: /\n\nUser-agent: *\nAllow: /\n' — paste the whole file, it is never fetched for you. Also callable without MCP, same implementation: GET https://www.pathwren.workers.dev/tools/robots-lint?robots_txt=<urlencoded>&s=client-dossiers — or POST the file as the raw body to the same URL.
check_path_allowed
FIRST CALL, needs nothing: {"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"no_arguments_lint_this_hosts_robots_txt","arguments":{}}} — Evaluate a pasted robots.txt for one crawler and one or more paths under RFC 9309: longest token match for the group, longest path pattern for the rule, Allow breaking a tie, * and $ supported. Returns allowed/disallowed per path with the exact line that decided it, and flags the cases where a merge-groups parser and a first-group-wins parser would disagree. Example: user_agent='GPTBot', paths=['/', '/blog'], with your robots_txt pasted in. Also callable without MCP, same implementation: GET https://www.pathwren.workers.dev/tools/robots-allowed?robots_txt=<urlencoded>&ua=GPTBot&path=/blog&s=client-dossiers
audit_ai_access
FIRST CALL, needs nothing: {"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"no_arguments_lint_this_hosts_robots_txt","arguments":{}}} — Evaluate a pasted robots.txt against every AI crawler in this index and return the two lists that matter: blocked and allowed, per operator and category. Also names the tokens in your file that match no known crawler (a typo blocks nothing) and separates the crawlers that document obedience from the ones observed ignoring robots.txt, which need an IP or WAF rule instead. Example: path='/' with your robots_txt pasted in — the verdict is per crawler, at that path. Also callable without MCP, same implementation: GET https://www.pathwren.workers.dev/tools/ai-access?robots_txt=<urlencoded>&s=client-dossiers
diff_robots_txt
FIRST CALL, needs nothing: {"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"no_arguments_lint_this_hosts_robots_txt","arguments":{}}} — Compare two versions of a robots.txt and report only the crawlers whose verdict actually changes at a given path — not the text difference. Answers 'did my edit do what I meant, and did it do anything else', including sitemap additions and whether the parse errors went up or down. Example: before='User-agent: *\nAllow: /\n', after=your edited file, path='/'.
merge_policy
FIRST CALL, needs nothing: {"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"no_arguments_lint_this_hosts_robots_txt","arguments":{}}} — Merge one of eight maintained robots.txt stances (block-ai-training, allow-ai-search-only, block-all-ai, block-datasets, block-disputed, block-seo-tools, allow-all, maximum-ai-visibility) into a robots.txt you already have, without touching a single rule you wrote: a token you already name keeps your rules and the stance's version is reported instead of applied. Example: stance='block-ai-training', robots_txt='User-agent: *\nAllow: /\n'.