crawl-census
crawl-census-client
Fragen, bevor du abrufst. Ein Drop-in-Client, der deinen Crawler davon abhält, Anfragen an Türen zu verschwenden, die geschlossen sind, und der verhindert, dass er Inhalte umgeht, die jemand verkaufen möchte.
Das Lesen von robots.txt beantwortet eine Frage und versteckt zwei andere. Gemessen über 23.482 Domains von Crawl Census:
2.874 Domains erlauben KI-Agenten in robots.txt und verweigern denselben Agenten dann an der Netzwerkgrenze. Ein Parser sieht die Erlaubnis; der Abruf liefert 403. Du zahlst für den Roundtrip und bekommst nichts.
208 Domains antworten einem KI-User-Agent mit
HTTP 402 Payment Required. Das ist ein Preis, keine Ablehnung. Es als Blockade zu behandeln, geht an Inhalten vorbei, die der Betreiber dir verkaufen möchte. Ein erneuter Versuch nimmt etwas, wofür sie Geld verlangen.
Keine Abhängigkeiten. Kein Schlüssel erforderlich.
MCP-Server
Dieselbe Messung wird als Remote-MCP-Server bereitgestellt, sodass ein Agent fragen kann, bevor er abruft, statt nachdem es fehlschlägt. Gelistet im offiziellen MCP-Registry als io.github.taylorsmithgg/crawl-census.
{ "mcpServers": { "crawl-census": { "url": "https://crawlcensus.com/mcp" } } }Tool | Antworten |
| Werden diese Domains meinen Agenten bedienen, ablehnen oder zur Kasse bitten? |
| Was veröffentlicht diese Volkszählung über meinen Crawler, und wie korrigiere ich es? |
| Die wichtigsten Ergebnisse als datierte Datensätze mit Nennern und Zitierzeilen |
| Der gespeicherte Audit für eine Domain |
| Eine Domain jetzt messen |
| Korpusweite Gesamtsummen |
Keine Authentifizierung für Lese-Tools. Streamable HTTP.
Related MCP server: domain-intel-mcp
Installation
npm i github:taylorsmithgg/crawl-census-client
pip install git+https://github.com/taylorsmithgg/crawl-census-clientVerwendung
import { politeFetch } from "crawl-census-client";
const r = await politeFetch("https://example.com/", { agent: "gptbot" });
if (r.skipped) console.log(r.verdict, r.reason); // disallow | refuse | pay
else process(await r.response.text());from crawl_census import polite_fetch
r = polite_fetch("https://example.com/", agent="gptbot")
if r.skipped:
print(r.verdict, r.reason)
else:
process(r.body)Überspringen wird zurückgegeben, nicht ausgelöst. Es ist das normale Ergebnis für einen großen Teil des Webs, und eine Crawl-Schleife sollte Überspringungen zählen können, ohne ein try/except um jede URL zu legen.
Eine Warteschlange vor dem Crawlen aufteilen
Ein Aufruf pro 1.000 Domains statt einer pro Host:
const { crawl, skip, pay, unknown } = await partition(urls, { agent: "gptbot" });p = partition(urls, agent="gptbot")
p.crawl, p.skip, p.pay, p.unknownOder einfach die Datei nehmen
Für einen Fetcher, der nur eine Deny-Liste im Speicher benötigt, überspringe die Pro-Domain-Aufrufe vollständig:
curl https://crawlcensus.com/agents/gptbot/blocklist.txt # one domain per line, commented headerconst sync = await syncBlocklist("gptbot"); // full list once
if (sync.blocked.has(host)) skip();
setInterval(() => sync.refresh(), 3600_000); // then deltas only, a few hundred bytessync = BlocklistSync("gptbot")
if host in sync: skip()
sync.refresh() # {'added': 3, 'removed': 1, 'size': 3310, 'cursor': ...}Der Delta-Feed ist https://crawlcensus.com/agents/<agent>/changes.json?since=<unix> und jede Antwort trägt next_since, sodass ein langlaufender Crawler mit ein paar hundert Bytes pro Stunde aktuell bleibt, statt die Liste erneut herunterzuladen.
Diese Datei deckt nur robots.txt ab. Edge-Ablehnung und HTTP 402 sind Verhaltensweisen pro Anfrage und benötigen weiterhin preflight oder politeFetch.
Was ein Crawl die Volkszählung kostet
Gemessen, nicht behauptet. Zwanzig gleichzeitig abgerufene Hosts kosteten früher zwanzig Preflight-Aufrufe mit je einer Domain; derselbe Host dreimal gleichzeitig angefordert kostete drei, weil der Cache erst nach der ersten Lookup-Auflösung hilft. Das anonyme Kontingent beträgt 240 Aufrufe pro Stunde, sodass ein Crawler sein Limit bei 240 Hosts erreichte, wenn ein Aufruf fünfundzwanzig abdeckt.
politeFetch teilt die Arbeit jetzt automatisch: Lookups, die im selben Tick ausgegeben werden, gehen als ein gebündelter Aufruf raus, und gleichzeitige Lookups für denselben Host warten auf eine einzige Anfrage.
Muster | vorher | jetzt |
20 Hosts, gleichzeitig | 20 Aufrufe | 1 Aufruf von 20 |
1 Host, 3 URLs, gleichzeitig | 3 Aufrufe | 1 Aufruf |
60 Hosts, gleichzeitig | 60 Aufrufe | 3 Aufrufe (25 / 25 / 10) |
| 2 Aufrufe | 1 Aufruf |
batchSize standardmäßig 25, das Pro-Aufruf-Limit ohne Schlüssel. Erhöhe es mit einem Pro- oder Data-Schlüssel. batchWaitMs erweitert das Zusammenführungsfenster für Nebenläufigkeit, die in Wellen statt auf einmal ankommt; der Standardwert von null leert beim nächsten Tick.
Bezahlen, wenn eine Quelle einen Preis nennt
Ein pay-Urteil trägt den Betrag, wenn die Quelle einen genannt hat:
const r = await politeFetch(url, { agent: "claudebot" });
if (r.verdict === "pay") console.log(r.price); // "USD 0.5", or null if none was quotedZwei Dinge sind wissenswert. Die meisten Quellen, die mit HTTP 402 antworten, nennen überhaupt keinen Betrag, also ist price normalerweise null und die Vereinbarung muss außerhalb der Reihe getroffen werden. Und die Preisgestaltung ist pro Crawler: Im gemessenen Korpus berechnen 78 von 213 kostenpflichtigen Quellen einigen Agenten Gebühren und bedienen andere kostenlos, also frage mit deinem eigenen Token, statt anzunehmen, dass eine Domain auf der Liste dich zur Kasse bittet.
Zwei Arten von Unbekannt
partition teilt eine Arbeitswarteschlange in crawl, pay, skip, unknown und undecidable.
Die letzten beiden sehen ähnlich aus und sind es nicht. unknown bedeutet, dass die Volkszählung diese Domain noch nicht gemessen hat: Reiche sie ein und der nächste Durchgang erhält ein echtes Urteil. undecidable bedeutet, dass die robots.txt der Website CrawlCensusBot nicht erlaubt, sodass diese Volkszählung sie nie messen wird – ein erneuter Versuch ist garantierte Verschwendung, und eine Schleife, die ihre Unbekannten bei jedem Durchgang erneut einreicht, würde diese für immer erneut einreichen. Der Server markiert den Unterschied mit einem measurable-Boolean; lies das, niemals den reason-Prosa.
const p = await partition(urls, { agent: "gptbot" });
await Promise.all(p.crawl.map(politeFetchOne));
if (p.unmeasured.length) await submitUnmeasured(p, { agent: "gptbot" });
// p.undecidable: read their robots.txt yourself. Asking us again cannot help.Die Einreichung ist absichtlich ein separater Aufruf. Eine Bibliothek, die während eines Lookups stillschweigend POSTs, ist ein schlechter Bürger, und du solltest wählen, wann deine Warteschlangenpositionen ausgegeben werden.
Alles überspringen, was dir nicht dienen wird
Eine Deny-Liste ist die kleinere Hälfte. Gemessen an der Live-Volkszählung gibt ein Crawler, der nur robots-Verbote überspringt, immer noch etwa 2.900 Anfragen pro Durchgang für Domains aus, die es in robots.txt erlauben und an der Grenze ablehnen, oder die mit HTTP 402 antworten – für PerplexityBot ist diese Menge größer als seine Deny-Liste. Diese Abrufe liefern nichts und kosten jeweils einen Roundtrip.
const skip = await syncSkipList("gptbot");
if (skip.has(host)) continue; // disallowed, refused at the edge, or priced
skip.why(host); // "disallow" | "pay" | "refuse" | null
setInterval(() => skip.refresh(), 3600_000);Agent | Deny-Liste | auch überspringbar | Gesamt |
GPTBot | 3.542 | 2.944 | 6.486 |
ClaudeBot | 3.169 | 3.194 | 6.363 |
PerplexityBot | 1.128 | 3.658 | 4.786 |
Die drei Mengen werden intern getrennt gehalten, sodass eine Änderung diejenige verschiebt, zu der sie gehört. why() folgt derselben Priorität wie Preflight: Ein Verbot hat Vorrang vor einem Preis, weil ein Preis keine Erlaubnis ist.
Eine Deny-Liste aktuell halten
syncBlocklist / BlocklistSync laden die Liste einmal herunter und wenden dann nur das an, was sich geändert hat.
Die Liste wird mit der genauen Position im Änderungsfeed geliefert, an der sie erstellt wurde, in einem x-cursor-Header und einem # cursor:-Kommentar. Die Clients lesen sie und setzen von dort fort, sodass es keine Lücke zwischen dem Snapshot und der ersten Abfrage gibt und keine Abhängigkeit davon, dass deine Uhr mit der des Servers synchron ist. Abfragen pro Sekunde können eine Position innerhalb einer Sekunde nicht ausdrücken, und eine Crawl-Batch schreibt Dutzende Ereignisse in eine, sodass eine Fortsetzung mit Sekundengranularität den Rest davon fallen lassen kann: Live gemessen, stellte die Fortsetzung nach dem ersten von drei Änderungen in derselben Sekunde beide Geschwister per Cursor wieder her und keines per Sekunde.
const sync = await syncBlocklist("gptbot"); // cursor comes from the list itself
if (sync.blocked.has(host)) skip();
setInterval(() => sync.refresh(), 3600_000); // a few hundred bytes per pollrefresh() wendet nur robots-Übergänge auf die Liste an, weil die Liste daraus besteht. Edge-Ablehnungen, neue Preise und llms.txt-Änderungen kommen in other zurück, damit du separat darauf reagieren kannst – eine frühere Version löschte diese Domains aus der Deny-Liste, sodass ein Crawler genau das wieder abrief, was gerade begonnen hatte, ihn abzulehnen.
Urteile
Die maßgebliche Definition jedes Urteils – was es bedeutet, was es einen Crawler zu tun verpflichtet und ob erneutes Fragen es ändern könnte – ist als Daten unter /api/v1/verdicts veröffentlicht. Die Liste unten ist eine Zusammenfassung; falls die beiden jemals abweichen, hat der Endpunkt recht und diese Datei ist veraltet.
politeFetch überspringt standardmäßig disallow, refuse und pay, was die abgeleitete do_not_fetch-Menge des Endpunkts ist. Die Kopie hier ist bewusst – eine Crawl-Schleife sollte keinen Netzwerkaufruf benötigen, um zu entscheiden – und ein Test vergleicht die beiden, sodass sie nicht unbemerkt abweichen kann.
Urteil | Bedeutung | Standardverhalten |
| robots.txt erlaubt diesen Agenten, und eine Live-Anfrage mit seinem User-Agent wurde bedient | abrufen |
| robots.txt verbietet diesen Agenten an der Site-Wurzel | überspringen |
| robots.txt erlaubt es; die Grenze lehnte es trotzdem ab. Die Erlaubnis ist nicht real | überspringen |
| Die Quelle antwortete mit HTTP 402. Sie wird diesen Agenten zu kommerziellen Bedingungen bedienen | überspringen |
| nicht kürzlich genug gemessen, um zu antworten | abrufen |
onPay: "fetch" (on_pay="fetch") überschreibt die Paywall-Standardeinstellung. Es ist ein explizites Opt-in und wird im Ergebnis als paidRouteOverridden aufgezeichnet, sodass es in deinen Logs erscheint.
Es degradiert, es scheitert nicht
Wenn die Volkszählung nicht erreichbar ist, wird jedes Urteil zu unknown und dein Crawl läuft wie gewohnt weiter. Ein Ausfall eines Drittanbieters darf deine Pipeline niemals stoppen. Es gibt einen Live-Test genau dafür.
Was wir über deinen Agenten veröffentlichen
const p = await agentProfile("claudebot");
// robots disallow rate, edge refusal rate, operator page, correction channelWenn eine Zahl falsch ist, ist der Korrekturkanal in dieser Antwort und auf deiner Betreiberseite. Registry-Fakten werden ohne Argument korrigiert; umstrittene Messungen werden zusammen mit dem Streit und den zugrunde liegenden Scan-Datensätzen veröffentlicht, statt stillschweigend geändert zu werden.
Grenzen
25 Domains pro Preflight-Aufruf anonym, 200 mit einem Pro-Schlüssel, 1.000 mit einem Data-Schlüssel. Übergib apiKey. Details unter https://crawlcensus.com/for-crawlers.
Tests
node test.mjs läuft absichtlich gegen die Live-Volkszählung. Der Wert dieses Clients liegt darin, ob seine Urteile der Realität entsprechen, und ein gemockter Test würde nur behaupten, dass der Mock mit sich selbst übereinstimmt.
MIT. Daten sind CC BY 4.0, Attribution als "Quelle: Crawl Census (crawlcensus.com)".
Available Tools
7 toolsagent_profileAInspect
What this census measures and publishes about one AI crawler: how often it is disallowed in robots.txt, how often live requests carrying its user agent are refused at the network edge whatever robots.txt says, whether its operator documents it as honouring robots.txt, and where to correct any of that. Intended for the operator of the agent as much as for anyone studying it, so it includes the correction channel and the public page a claim can be disputed against.
| Name | Required | Description | Default |
|---|---|---|---|
| agent | Yes | Crawler token, e.g. gptbot, claudebot, ccbot, google-extended. |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the behavioral burden and does so well: it discloses what is measured, that live requests are checked at the network edge, that operator documentation is assessed, and that correction/dispute channels are included. It does not explicitly state read-only status or error behavior, but the 'measures and publishes' framing strongly implies a read operation.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The purpose is front-loaded and the metric list is scannable. The second sentence slightly repeats the correction-channel idea already mentioned in the list, but it adds the audience and the dispute-page detail, so it earns its place.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a single-parameter tool with no output schema, the description adequately conveys what data the profile returns and that correction channels are included. It could be more explicit about output format or unknown-agent handling, but the essential guidance for selecting and invoking the tool is present.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The input schema already documents `agent` with examples like gptbot and claudebot at 100% coverage. The description only adds that the tool is about 'one AI crawler,' contributing no new parameter syntax or constraints, so baseline 3 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description opens with a specific verb+resource: 'What this census measures and publishes about one AI crawler.' It then enumerates the exact metrics reported, clearly distinguishing this per-agent profile tool from sibling tools that focus on sites, stats, or submissions.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The intended use is clear: retrieve published census data about one AI crawler, aimed at both the crawler operator and external researchers. It does not explicitly name alternative sibling tools or exclusion conditions, but the usage context is unambiguous.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
census_factsAInspect
Every headline finding from the census as discrete, dated records rather than prose. Each carries its value, unit, denominator, measurement date, the page it comes from and a ready-made citation line, plus the caveats that apply to all of them. Use this when answering a question about how open the web is to AI crawlers: lifting a percentage out of a rendered page loses the denominator and the date, which is what makes the number wrong when it is repeated.
| Name | Required | Description | Default |
|---|---|---|---|
No parameters | |||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden, and it does so well. It discloses the structure of each returned record, the presence of caveats, and the important failure mode of losing denominators and dates when numbers are repeated. This gives an agent a clear picture of the tool's behavior.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two dense, well-front-loaded sentences cover what the tool returns, how records are structured, and when to use it. Every clause earns its place, with no filler or repetition.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a zero-parameter tool with no output schema, the description is remarkably complete: it explains the record fields, caveats, and the specific use case. An agent can understand what it will get back and why it is the right tool without further clarification.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The input schema has zero parameters, so this is the baseline-4 case. The description focuses on output record semantics rather than parameters, which is appropriate since there is nothing to document.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states that this tool returns census headline findings as discrete, dated records with value, unit, denominator, date, page, and citation. It distinguishes itself from prose-style reporting, but it does not explicitly differentiate itself from the sibling census_stats, so some overlap remains.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It gives an explicit 'Use this when...' trigger tied to questions about how open the web is to AI crawlers, and explains why the dated/denominator-preserving format matters. It does not mention alternatives or when not to use it, so routing guidance is strong but not complete.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
census_statsBInspect
Corpus-level statistics: how many measured domains block each AI crawler, mean access score, llms.txt adoption.
| Name | Required | Description | Default |
|---|---|---|---|
No parameters | |||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden of disclosing behavior. It states what data is included but does not reveal whether it is read-only, how recent the statistics are, whether any parameters or filters exist, or what the response structure looks like. The colon-led list of statistics is content, not behavioral transparency.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is a single concise sentence that leads with the core concept ('corpus-level statistics') and then lists specific examples. There is no filler or redundant language, making it easy to parse.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a parameterless tool, the description gives enough to understand what kind of data comes back, but it omits an explicit return format and does not clarify the scope of 'measured domains' or any access prerequisites. The missing output schema means the description could reasonably be expected to say more about the result shape.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The tool has zero parameters, so the schema fully covers any input concerns. The description adds value by explaining what the resulting statistics measure, which complements the empty schema without needing to compensate for undocumented parameters.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description names the resource ('corpus-level statistics') and specifies three concrete metrics: per-crawler blocking counts, mean access score, and llms.txt adoption. This gives an agent a clear idea of what the tool computes, though it does not explicitly distinguish itself from the similarly named sibling census_facts.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The phrase 'corpus-level statistics' implies this is for aggregate data, but there is no explicit statement of when to use this tool versus alternatives like census_facts or scan_site. No when-not conditions or alternative names are provided.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
crawl_preflightAInspect
Decide whether a crawler may fetch a list of domains before spending requests on them. Works for any crawler token, not only the ones this census tracks: an unrecognised agent is resolved from each domain's stored robots.txt rather than refused. For each domain returns one of: allow (robots permits it and a live request carrying that agent's user agent was served), disallow (robots.txt forbids it), refuse (robots permits it but the edge refused the agent anyway, so the allowance is not real), pay (the origin answered HTTP 402 Payment Required, meaning it will serve this agent on commercial terms), or unknown. The full definition of each, including what it obliges a crawler to do, is published at https://crawlcensus.com/api/v1/verdicts. Built for crawler operators rather than site owners: it prevents wasted fetches against doors that are shut, and flags content an operator is trying to sell rather than withhold.
| Name | Required | Description | Default |
|---|---|---|---|
| agent | Yes | Crawler token, e.g. gptbot, claudebot, perplexitybot, oai-searchbot, ccbot. | |
| domains | Yes | Domains to check. Up to 25 per call anonymously; send an Authorization: Bearer key for more. An over-large batch is refused outright rather than partly answered. |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full burden and goes beyond the basics: it reveals that a live request is sent to verify serving, that unrecognised agents are resolved from robots.txt rather than refused, and that 'refuse' means an allowance is not real. It also links to full verdict definitions. Minor omissions like rate-limit behavior are already covered in the schema.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is dense but every sentence earns its place: purpose, verdict list, unknown-agent behavior, authoritative link, and audience. It is front-loaded with the core decision purpose. Slightly longer than necessary, but no filler or repetition.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
The description is complete despite having no output schema: it enumerates all possible return verdicts with definitions, explains edge-case behavior for unknown agents, and provides a link for full semantics. Combined with a 100%-covered input schema, an agent has all needed information to invoke the tool correctly.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100%, so baseline is 3. The description adds meaningful context for the 'agent' parameter by explaining it works for any crawler token and how unrecognised agents are handled, which goes beyond the schema's list of examples. It also clarifies the 'domains' parameter's per-domain output semantics.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
Description opens with a specific verb+resource ('Decide whether a crawler may fetch a list of domains'), then enumerates the five possible verdicts with precise meanings. It also distinguishes itself from sibling census/site tools by stating it is 'Built for crawler operators rather than site owners' and by handling 'any crawler token, not only the ones this census tracks.'
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Explicitly tells when to use the tool ('before spending requests on them') and for whom ('crawler operators rather than site owners'), which excludes site-owner workflows that would be served by other siblings. It also explains the unrecognised-agent behavior, aiding correct selection for non-census crawlers.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
scan_siteAInspect
Run a live AI-accessibility audit of a domain: robots.txt policy for every tracked AI crawler, live user-agent probes, JavaScript-free readability, structured data and llms.txt. Returns a score out of 100 with per-check detail.
| Name | Required | Description | Default |
|---|---|---|---|
| domain | Yes | Bare hostname, for example example.com |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden of disclosure. It transparently explains that the tool performs live probes, checks robots.txt and llms.txt, and returns a score with per-check detail. It does not mention potential side effects or operational caveats, but the core behavior is well disclosed.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
A single information-dense sentence that front-loads the purpose and uses a compact list to convey scope, then states the return format. No filler or redundancy.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a tool with one parameter and no output schema, the description is largely complete: it explains what checks are performed and what the return value looks like (score out of 100 with per-check detail). Minor gaps are the lack of alternative routing and any timing/side-effect context, but nothing critical is missing.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, and the single parameter 'domain' is already well documented with an example. The tool description adds no additional parameter semantics beyond what the schema provides, so the baseline of 3 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states a specific verb ('Run') and resource ('a live AI-accessibility audit of a domain'), and enumerates concrete checks. It does not explicitly distinguish itself from sibling tools like site_report or crawl_preflight, but the scope is specific enough that an agent can infer its function.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description implies when to use it: when a live AI-accessibility audit of a domain is needed. However, it gives no explicit guidance on when to choose this tool over siblings such as site_report or crawl_preflight, and offers no exclusions or prerequisites.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
site_reportAInspect
Return the most recent stored audit for a domain without triggering a new scan. Faster and free of load on the target site.
| Name | Required | Description | Default |
|---|---|---|---|
| domain | Yes | Bare hostname |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the burden. It discloses the key behavioral traits: it is a read of stored data, it does not trigger a scan, and it imposes no load on the target. It stops short of describing behavior when no stored audit exists, but the main side-effect profile is clear.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two sentences with no wasted words; the primary action and the no-scan guarantee are front-loaded, followed by a benefit. Every phrase earns its place.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a simple one-parameter read-only report tool with no output schema, the description covers the core contract: what is returned, the absence of a scan, and the speed/load benefit. It does not specify the return format or error behavior, but the tool's simplicity keeps these gaps minor.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The input schema already describes domain as 'Bare hostname' with 100% coverage, so the description adds no additional parameter meaning. Baseline 3 applies because the schema handles parameter documentation.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb ('Return'), resource ('most recent stored audit for a domain'), and explicitly distinguishes itself from a scan by saying it does not trigger a new scan. This makes its purpose clear and differentiates it from the sibling scan_site.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The phrase 'without triggering a new scan' plus 'Faster and free of load' gives clear context for when to use this tool: when a stored report is acceptable and no active scan is desired. It does not explicitly name scan_site as the alternative, but the intended use case is evident.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
submit_domainsAInspect
Queue domains the census has not measured yet so a later crawl_preflight can answer them. This closes the loop crawl_preflight starts: anything it returns as unknown with measurable true is worth submitting, and the reply names any that were already fresh or that this census will never measure, so a caller looping over its own unknowns converges instead of resubmitting the same set. Queueing is a database write rather than a fetch, so the allowance is far higher than scan_site and submitted domains are measured ahead of the ranked backlog.
| Name | Required | Description | Default |
|---|---|---|---|
| domains | Yes | Hostnames to queue. Up to 50 per call anonymously; an over-large batch is refused outright rather than partly queued. |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description correctly discloses the core side effect: 'Queueing is a database write rather than a fetch.' It also reveals reply behavior, naming already-fresh or never-measured domains, though exact rate limits and idempotency semantics are not fully specified.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Three sentences pack the purpose, workflow, and operational distinction without filler. The first sentence front-loads the core action, while the later sentences add necessary context about the crawl_preflight loop and the allowance difference from scan_site.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a one-parameter mutation tool with no annotations and no output schema, the description covers when to call, what to submit, the side effect, and the response's role in convergence. It leaves numeric limits and idempotency guarantees implicit, but enough information exists for correct invocation.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100% with a clear field description, so the parameter itself is well documented. The tool description adds value by defining eligibility: only domains the census has not measured yet, specifically those flagged by crawl_preflight as unknown with measurable true.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific verb and object: 'Queue domains the census has not measured yet.' It also explicitly ties the tool to crawl_preflight's 'unknown with measurable true' results, distinguishing it from retrieval-focused siblings like scan_site and site_report.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It gives an explicit selection rule: anything crawl_preflight returns as unknown with measurable true is worth submitting, and it warns that fresh or never-measured domains appear in the reply so a caller can avoid resubmission. It also contrasts the database-write allowance with scan_site, helping an agent choose between them.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Tool Schema Changelog
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
7 tool updates
v1.0.0- First observed
agent_profile - First observed
census_facts - First observed
census_stats - First observed
crawl_preflight - First observed
scan_site - First observed
site_report - First observed
submit_domains
TDQS
Scored across 7 tools
scan_site and site_report both return audits for a domain, but one is a live scan and the other is a stored result, so they are distinguishable. census_stats and census_facts also overlap somewhat as corpus-level outputs, but one gives direct statistics and the other gives citation-ready findings. The remaining tools each have clearly separate roles.
All names are lowercase snake_case and mostly combine a domain noun with a result or action, such as site_report, census_stats, agent_profile, and crawl_preflight. scan_site and submit_domains are verb-first while the others are noun-first, so the pattern is not perfectly uniform, but the style is still readable and predictable.
Seven tools is a well-scoped set for a crawl-census service: each tool covers a distinct consumer need, from live audits and stored reports to crawler preflight decisions, agent profiles, citation-ready facts, and domain submission. No tool is redundant, and the count feels appropriately sized for the domain.
The set covers the main workflows well: running and retrieving audits, querying corpus statistics and facts, profiling individual crawlers, deciding whether to fetch domains, and queueing unmeasured domains. Minor gaps include no obvious way to list all tracked agents or remove queued submissions, but these are not core to the documented purpose.
Maintenance
Related MCP Connectors
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