ndl-mcp
ndl-mcp
Un servidor MCP para buscar en 国立国会図書館サーチ (NDL Search), operado por la Biblioteca Nacional de la Dieta de Japón, a través de la interfaz SRU searchRetrieve.
Tercero de una serie con cinii-mcp y jstage-mcp, y comparte su sobre de respuesta: consulta y script tipados, modo de coincidencia, amplitud gradual, matched_in por elemento, diagnósticos tipados, un recibo registrable, atribución.
Antes de ejecutar esto
No hay credencial. Las API de búsqueda de NDL son abiertas. Sin clave de API, sin ID de aplicación, sin token, nada que pegar en un archivo de configuración. Si estás esperando que llegue algo antes de poder usar esto, estás esperando algo que no va a llegar.
Sigue habiendo una obligación. La sección 17 de APIのご利用について pide a los usuarios continuos de la API que informen de sus datos de contacto y la naturaleza de su uso a través del formulario de solicitud — 「事前の利用申請の要否にかかわらず」, tanto si se requiere una solicitud de uso previa como si no. Una 利用申請 formal solo se requiere para uso generador de ingresos; la notificación se pide a todos los que acceden de forma continua.
Como el acceso no depende de la presentación, nada en el mundo te impedirá omitirla. Así que install.ps1 te lo impide: se niega a registrar el servidor hasta que se registre la notificación, y escribe la fecha en NDL-API-NOTIFICATION.txt.
.\install.ps1 -NotificationFiled 2026-08-19Ejecútalo sin la bandera e imprime la URL del formulario, ofrece abrirlo y sale.
Related MCP server: jp-lit-mcp
Lo que el servidor no hará
Los compromisos siguientes se presentaron ante la NDL. Están implementados, no aspirados, y la prueba de humo del instalador afirma los tres primeros:
Compromiso | Implementación |
Solicitudes emitidas en serie; sin acceso concurrente |
|
Intervalo mínimo de un segundo |
|
Un límite de registros por búsqueda; sin recuperación masiva |
|
La interfaz de recolección no se utiliza | OAI-PMH no está implementado |
Crédito en cada respuesta |
|
Metadatos mostrados, no acumulados | sin caché, sin almacenamiento local |
Cambia cualquiera de ellos y estarás cambiando lo que se declaró a una biblioteca nacional. Presenta primero una notificación complementaria.
Proveedores
Solo los cinco conjuntos declarados en la solicitud son accesibles. Todos son creados por NDL y CC BY, y ninguno requiere una solicitud de uso:
dpid | 名称 |
| 国立国会図書館蔵書 |
| 国立国会図書館全国書誌情報 |
| 国立国会図書館雑誌記事索引 |
| 国立国会図書館雑誌記事索引オンライン資料編 |
| 国立国会図書館デジタルコレクション(オープンデータ) |
ndl-dl y ndl-dl-online — las Colecciones Digitales más amplias — están marcados con △ en la lista de proveedores y requieren una solicitud que no se ha realizado. Una solicitud que los nombre se rechaza en el proceso, con un diagnóstico DPID_NOT_PERMITTED, en lugar de enviarse.
Herramientas
Herramienta | Conjunto buscado |
| 蔵書 |
| 全国書誌情報 |
| 雑誌記事索引 (ambos conjuntos) |
| デジタルコレクション(オープンデータ) |
| los cinco |
| un registro por |
Campos de búsqueda: title, creator, publisher, subject, anywhere, ndc, isbn, issn, from_year, to_year. Se combinan con AND; title, creator, publisher y subject coinciden parcialmente, ndc por prefijo, identificadores exactamente.
ndl_get_record es una recuperación, por lo que su sobre omite searched_for — no se eligió ningún término.
Dos cosas que morderán
Un AND, OR o NOT en mayúsculas dentro de un término de búsqueda hace que NDL rechace toda la consulta. No "no devuelve nada" — rechaza. La regla distingue mayúsculas y minúsculas tal como la especificación la establece: War AND Peace se detecta, War and Peace pasa. El servidor comprueba antes de enviar y devuelve un diagnóstico RESERVED_WORD_IN_QUERY nombrando el campo infractor, en lugar de dejar que la biblioteca responda con un error de análisis.
NDL impone un límite de velocidad que no cuantificará, y responde con HTTP 429. La página de ayuda solo dice 「同時リクエスト数には制限を設けています」 y se niega a publicar una cifra. En las pruebas del 19 de agosto de 2026, un 429 llegó muy por debajo de una solicitud sostenida por segundo — así que el mínimo de un segundo presentado ante la biblioteca es un mínimo, no una garantía. Un 429 compra una sola espera, respetando Retry-After, y luego el servidor se detiene en lugar de presionar. Informa RATE_LIMITED, deliberadamente distinto de API_ERROR, porque los dos significan cosas diferentes para un lector: una búsqueda limitada por velocidad tiene un resultado desconocido, no uno vacío, y nunca debe escribirse como una ausencia.
Un término romanizado devolverá menos resultados. NDL Search indexa registros en japonés con escritura japonesa. Una consulta en escritura latina contra un corpus japonés es la trampa del romaji, y el sobre eleva SCRIPT_LATIN_QUERY para ello. El titular searched_for existe para que el término que el asistente realmente eligió sea visible en la parte superior de la respuesta en lugar de enterrado — ese es el propósito del campo, y la razón por la que una divulgación puede informar los términos que usó una búsqueda.
Recibos
mediation.emit() escribe cada sobre de respuesta en el libro mayor de solo añadir y encadenado por hash en MCP_RECEIPT_LOG, que install.ps1 establece al mismo archivo que usan los otros servidores. Si no se establece la variable, no se escribe nada y no falla nada.
Observa lo que contiene el libro mayor y lo que no: la consulta, el término normalizado, los parámetros enviados, la marca de tiempo, un SHA-256 sobre la consulta y los parámetros, y los identificadores de los registros devueltos. No contiene los registros bibliográficos en sí. Registrar una consulta no es acumular una base de datos, y el compromiso contra la acumulación no se viola al mantener el recibo — pero la distinción vale la pena declararla en lugar de asumirla, porque los dos se ven similares desde fuera.
Por qué solo SRU
La solicitud declara SRU y OpenSearch. Este servidor implementa solo SRU, que es menos de lo declarado y por lo tanto seguro — siempre puedes usar menos de lo que le dijiste a la biblioteca que usarías.
La razón es probatoria. El formato de respuesta de OpenSearch no está documentado en la especificación 第1.4版: sin tabla de elementos, sin muestra, y los apéndices cubren solo SRU y OAI-PMH. Peor aún, la especificación establece que un parámetro malformado devuelve una respuesta de cero resultados en lugar de un error — 「引数(パラメータ)誤りの場合には検索結果ゼロ件となる」 — así que un error tipográfico en un nombre de campo es indistinguible de una ausencia genuina. Para una herramienta cuyo propósito es permitir que un historiador confíe en que no se encontró nada, eso es descalificante. SRU devuelve diagnósticos tipados y un esquema de registro DC-NDL documentado. Añadir OpenSearch más tarde no necesita una nueva notificación; necesita un formato de respuesta documentado.
Fuentes
国立国会図書館サーチ 外部提供インタフェース仕様書 第1.4版 (2026-03-31)
APIのご利用について — términos, requisito de crédito, concurrencia, notificación
API提供対象データプロバイダ一覧 — valores de dpid y condiciones de licencia
Licencia
MIT. Los metadatos recuperados a través de este servidor son CC BY 4.0 de la Biblioteca Nacional de la Dieta; la línea de crédito que emite el servidor es la atribución que esa licencia requiere, y debería sobrevivir en cualquier cosa que publiques a partir de los resultados.
Qué se ha probado y qué no
Verificado contra la API en vivo el 19 de agosto de 2026:
Búsqueda en escritura japonesa en 蔵書 y 雑誌記事索引 — totales correctos, registros correctos, años e identificadores correctos.
Análisis de DC-NDL, incluido el filtro de stub de manifestación. NDL devuelve dos elementos
BibResourcepor registro; tomar ambos duplicaba el conjunto de resultados con espacios en blanco hasta que se añadió el filtro.searched_forinforma el término elegido, no el CQL ensamblado, por lo que su detección de escritura es significativa; el CQL exacto se lleva enquery.paramsy está fijado por el hash del recibo.La protección
DPID_NOT_PERMITTED: una solicitud que nombrendl-dlse rechaza en el proceso.RESERVED_WORD_IN_QUERY:War AND Peacedetectado,War and Peacepasó.El limitador de velocidad, involuntariamente — ver HTTP 429 arriba.
No verificado contra la API en vivo, y leído en lugar de ejecutado: el paso directo de "El registro no existe", ndl_get_record y la ruta de espera. Las pruebas se detuvieron en el 429 en lugar de continuar, porque caracterizar un límite de velocidad no divulgado sondeándolo es precisamente el 継続して大量のアクセス que los términos advierten, y el punto de este servidor no es ser la cosa que la Biblioteca Nacional de la Dieta tenga que bloquear. Ejercita esas rutas en uso ordinario, una consulta a la vez.
Available Tools
6 toolsndl_get_recordARead-onlyIdempotent
Retrieve a single record by NDL bibliographic ID or 全国書誌番号 (JP number).
A fetch, not a search: the envelope omits searched_for because no term was
chosen. Exactly one identifier is required.
| Name | Required | Description | Default |
|---|---|---|---|
| params | Yes |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds useful behavioral detail beyond annotations by explaining that the envelope omits 'searched_for' because no search term is chosen, which gives the agent insight into the response format.
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 short sentences convey the purpose and the key operational distinction. The description is front-loaded with the primary action, and every sentence adds relevant information with no filler.
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-record fetch tool, the description is complete: it covers the identifier requirement, the fetch-vs-search distinction, and a response envelope nuance. The output schema and annotations handle return format and safety, so nothing essential is missing for the agent to invoke this 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?
With schema description coverage reported at 0%, the description partially compensates by naming both accepted identifier types: NDL bibliographic ID and 全国書誌番号. It also adds the critical constraint that exactly one identifier is required, which is not enforced by the schema (both params are individually optional). However, it does not elaborate on identifier format or which identifier should be preferred when both are known.
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 uses a specific verb and resource: 'Retrieve a single record by NDL bibliographic ID or 全国書誌番号 (JP number).' It further distinguishes itself from the search sibling tools by explicitly stating 'A fetch, not a search,' so an agent can clearly tell it apart.
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 gives clear context: this tool is for fetching by a known identifier, not for searching. It also provides a key usage requirement, 'Exactly one identifier is required,' which helps the agent avoid invalid calls. It does not explicitly name alternative tools, but since all siblings are search tools, the contrast is sufficient.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
ndl_search_allARead-onlyIdempotent
Search all five declared provider sets at once.
Use when the material type is unknown. For a bibliographic check, the narrower tools return a cleaner set.
| Name | Required | Description | Default |
|---|---|---|---|
| params | Yes |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly, openWorld, idempotent, and non-destructive behavior, so the description doesn't need to restate safety. It adds the useful behavioral context that one call hits all five provider sets at once. It doesn't disclose behaviors like result merging, duplication, or pagination, but with strong annotations and an output schema this is acceptable.
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 filler: the core action is front-loaded, and the usage guidance follows immediately. Every sentence carries meaning.
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 an aggregate search tool with read-only annotations, rich nested parameter descriptions, and an output schema, the description covers the key decision (when to use all vs. narrower). It would be slightly stronger if it named the five provider sets or the narrower sibling tool names, but the sibling list and schema supply that context.
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 description says nothing about parameters. Reported schema description coverage is 0% at the top level, and the description does not compensate by explaining search fields or constraints. The nested schema does contain useful per-field descriptions (ndc, isbn, title, year, etc.), which prevents this from being a 1.
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 and resource: 'Search all five declared provider sets at once.' This distinguishes it from the narrower sibling search tools by scope (all sets vs. one set), so an agent can tell it apart from ndl_search_books, ndl_search_articles, etc. without opening the schema.
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 condition — 'Use when the material type is unknown' — and an explicit alternative condition: 'For a bibliographic check, the narrower tools return a cleaner set.' The alternative names aren't listed verbatim, but the sibling list makes them identifiable.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
ndl_search_articlesARead-onlyIdempotent
Search 国立国会図書館雑誌記事索引, including the online-materials set.
The index covers Japanese periodical articles, including many not in CiNii or J-STAGE. It indexes articles, not their full text.
| Name | Required | Description | Default |
|---|---|---|---|
| params | Yes |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already mark the tool as readOnly, idempotent, and non-destructive. The description adds useful behavioral context: it includes the online-materials set, covers articles often missing from CiNii/J-STAGE, and explicitly does not provide full text. No contradiction with annotations.
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 short, purposeful sentences with no filler. The action and resource are front-loaded, followed by scope and a clear limitation. Every sentence 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 search tool with a rich schema and an output schema, the description adequately explains what is searched, the coverage scope, and the key limitation (no full text). It could be more explicit about sibling routing, but overall it is complete enough 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?
The tool description itself does not describe any parameters, but the nested SearchInput schema gives detailed descriptions for each field (e.g., partial match, date formats, bounds). The description adds no extra parameter meaning, and the structured schema already carries the burden.
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 and resource: 'Search 国立国会図書館雑誌記事索引', then clarifies that it covers Japanese periodical articles and indexes articles, not full text. This makes it easy to distinguish from sibling tools like ndl_search_books or ndl_search_national_bibliography.
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 clear context on when this tool is relevant: for Japanese periodical article records, including coverage beyond CiNii and J-STAGE. It does not explicitly name sibling tools or state when not to use them, but the scope is clear enough for an agent to route correctly.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
ndl_search_booksARead-onlyIdempotent
Search 国立国会図書館蔵書 for books and monographs.
Fields are combined with AND; title, creator, publisher and subject match partially. Returns the unified response envelope. Records are displayed, not stored.
| Name | Required | Description | Default |
|---|---|---|---|
| params | Yes |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already mark the tool read-only and idempotent, and the description adds meaningful behavioral detail: fields are combined with AND, title/creator/publisher/subject match partially, it returns the unified response envelope, and records are displayed but not stored. This clearly communicates side effects and result shaping, and it does not contradict any annotation.
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 terse sentences: the first states purpose, the second states matching behavior, the third states output and side-effect semantics. No filler words, no repetition of schema details, and the most important information is front-loaded.
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, together with a rich input schema and an output schema, gives an agent enough to invoke the tool correctly: scope, query combination semantics, return envelope, and non-storage behavior. It falls short only in not explicitly routing the agent away from sibling search tools or mentioning pagination parameters, though those are documented in the schema.
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 description names a few parameters (title, creator, publisher, subject) and notes they match partially, but the input schema already documents each field with equivalent or richer descriptions. The main addition beyond the schema is 'fields are combined with AND', which is useful but modest. Given the schema descriptions are strong, 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 states a specific action ('Search'), a concrete resource ('国立国会図書館蔵書'), and a clear scope ('books and monographs'). This distinguishes it from sibling tools like ndl_search_articles or ndl_search_digital_open without needing to inspect their schemas.
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 this tool is for searching books and monographs rather than articles or digital collections, but it never explicitly names alternatives or says when to prefer this tool over sibling searches. It does provide practical query semantics (AND combination, partial matching), but not exclusion guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
ndl_search_digital_openBRead-onlyIdempotent
Search 国立国会図書館デジタルコレクション(オープンデータ).
The open-data set only. The wider Digital Collections (ndl-dl, ndl-dl-online) are marked ○ for 非営利 use and so need no usage application, but they were outside the set this server declares and their metadata carries no open licence — displayable, not redistributable. Adding them is a documentation change here, not an application to the library.
| Name | Required | Description | Default |
|---|---|---|---|
| params | Yes |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already provide readOnlyHint, idempotentHint, and destructiveHintfalse, so the safety profile is covered. The description adds value by clarifying the data set scope and licensing: only open-data records are included, and the wider collections are 'displayable, not redistributable'. This is useful behavioral context about what the tool can return, though it does not describe response format or limits.
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 compact and well-structured: a one-line purpose statement in Japanese, then a concise English explanation of the key scope constraint and licensing nuance. It front-loads the main action and does not waste words, though the language mix is slightly awkward for an English-first agent.
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?
Given the tool has an output schema and annotations cover read-only/idempotent behavior, the description’s main job is scoping and usage guidance. It handles scoping well and adds useful licence context, but it leaves out any explicit guidance on when to choose this over siblings like ndl_search_books or ndl_search_all, and it does not mention pagination or result count controls (though those are in the schema). Overall it is adequate but not thorough.
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 description contains no parameter information. Context signals report 0% schema description coverage, so the description must compensate but does not. The nested schema fields have some descriptions, but the top-level 'params' parameter is undocumented in the description, leaving an agent to delve into the $ref to construct a query. The description's licence discussion gives no help with the many search fields.
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 clear verb and resource: 'Search 国立国会図書館デジタルコレクション(オープンデータ)', reinforced by the annotation title 'Search NDL Digital Collections (Open Data)'. It distinguishes from the wider Digital Collections by explicitly saying 'The open-data set only', so an agent can tell this tool is scoped to the open subset. It does not name sibling search tools, but the scoping qualifier differentiates enough.
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 gives context about when to use this tool: it searches only the open-data set, and the wider collections are explicitly excluded. It does not name alternative tools or say 'use X for the wider collections', but the scope limitation clearly implies this tool is for open data. The licence discussion adds context about the data set, but no explicit when-not-to-use or alternative routing.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
ndl_search_national_bibliographyARead-onlyIdempotent
Search 国立国会図書館全国書誌情報.
The national bibliography is the authority for Japanese imprint data — use it when a publication date, publisher or edition statement has to be right rather than merely plausible.
| Name | Required | Description | Default |
|---|---|---|---|
| params | Yes |
Output Schema
| Name | Required | Description |
|---|---|---|
| result | Yes |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, idempoentHint=true, openWorldHint=true, and destructiveHint=false, covering safety and side-effect profile. The description adds only the data-quality trait (authority of imprint data), which is contextual but not a behavioral disclosure such as result ordering, matching semantics, or limits. It adds some value beyond annotations but does not carry new behavioral information.
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, zero redundancy. The resource and action are front-loaded, and the second sentence earns its place by explaining why this tool exists and when it matters.
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?
An output schema exists, every parameter is documented in the schema, and annotations cover the operational profile, so the description need not explain return values or side effects. What it adds — the authority positioning and the when-to-use rule — completes the picture for correct selection. A brief note distinguishing it from ndl_search_books or ndl_search_all would make it complete, hence not a 5.
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 0% — the tool description contributes nothing about the 12 parameters, though the schema itself documents each property well. The phrase "publication date, publisher or edition statement" faintly hints at which search fields matter, but that is indirect and does not compensate for the coverage gap.
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 resource — "Search 国立国会図書館全国書誌情報" — and then sharpens the scope by positioning this as the authoritative source for Japanese imprint data. The "authority" framing distinguishes it from sibling search tools without ambiguity: this is the tool to trust for dates, publishers, and edition statements.
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 gives clear when-to-use guidance: choose this tool when a publication date, publisher, or edition statement must be authoritative rather than merely plausible. It stops short of naming alternative siblings or stating when NOT to use it, so a score of 5 would overstate its completeness.
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.
6 tool updates
v1.1.0- First observed
ndl_get_record - First observed
ndl_search_all - First observed
ndl_search_articles - First observed
ndl_search_books - First observed
ndl_search_digital_open - First observed
ndl_search_national_bibliography
TDQS
Scored across 6 tools
Each search tool targets a distinct NDL dataset or scope, and get_record is clearly separate as an ID-based fetch. The main ambiguity is between ndl_search_books and ndl_search_national_bibliography, since both can return book-like records, though their descriptions clarify holdings vs. authority data.
All tool names follow a predictable ndl_<action>_<scope> pattern: get_record and search_* for the rest. This makes the set easy to navigate and avoids stylistic mixing.
Six tools is well-scoped for the server's purpose: one record retrieval tool and five search tools covering separate NDL data sources plus a combined search. No tool feels redundant or out of place.
The set covers the main NDL search surfaces and record retrieval by ID, which supports core bibliographic workflows. The main minor gap is that only the open Digital Collections subset is exposed, while wider digital collection content is not covered by a dedicated tool.
Maintenance
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