canonical: https://jentic.com/apis/isbndb.com/isbndb-isbndb-api

# ISBNdb API

Jentic publishes the only available OpenAPI specification for ISBNdb API, keeping it validated and agent-ready. ISBNdb provides programmatic access to a commercial bibliographic database of over 30 million books, authors, publishers, and subjects. Lookup by ISBN, name, or full-text query returns structured records with metadata such as title, author list, publication year, binding, dimensions, and dewey classification. The same API surface is mirrored under the vendor's `main` slug - the `isbndb-api` slug carries the YAML-source variant of the spec.

## For AI agents

Look up books, authors, publishers, and subjects in the ISBNdb commercial bibliographic database - fetch by ISBN, search by name, or run a global keyword query.

## Scope

Does not handle full-text content, e-book downloads, or library borrowing - use for bibliographic metadata lookup only.

## Capabilities

- Resolve a 10 or 13-digit ISBN to a full book record with title, authors, publisher, and year
- Search the catalogue by free-text query and paginate through matching books
- Fetch the bibliography of a specific author including all books attributed to them
- Retrieve the full title list and metadata for a given publisher
- Look up a Library of Congress subject heading and return the books filed under it
- Run a federated search across books, authors, publishers, and subjects in a single call

## Use cases

### Library catalogue enrichment

Enrich an internal book catalogue with authoritative bibliographic metadata so search, filtering, and recommendations work against a consistent schema. The agent calls GET `/book/{isbn}` for each row and merges the response - title, author list, binding, publication year - back into the local record. ISBNdb covers over 30 million titles, which is enough to resolve most consumer and academic catalogues without falling back to manual cleanup.

Example prompt: For each ISBN in the supplied list, call GET `/book/{isbn}` and write the returned title and authors back to the local record

### Author bibliography page generation

Render an author landing page with their full back catalogue without scraping retail sites. The agent calls GET `/author/{name}` to retrieve the bibliography, then GET `/book/{isbn}` on each result for cover and binding details. The pipeline finishes in one or two API rounds per author and avoids the legal grey zone of scraping Amazon or Goodreads.

Example prompt: Fetch the bibliography for 'Ursula K Le Guin' and return the 10 most recent titles with publication years

### Subject-driven reading list generation

Produce themed reading lists by querying ISBNdb's subject index. The agent retrieves a subject record via GET `/subject/{name}`, then expands each title with GET `/book/{isbn}` for full metadata. Useful for educational platforms generating curriculum-aligned reading lists or for retail sites building topical landing pages.

Example prompt: Look up the subject 'climate change' and return the first page of books with their titles, authors, and ISBNs

### AI agent answering book metadata questions

An AI agent fielding consumer questions about books needs a structured fact source. Through Jentic the agent searches for 'lookup ISBN' or 'search books by author', loads the matching ISBNdb operation, and returns a verified record instead of a hallucinated one. Pairs naturally with retrieval-augmented generation pipelines that need ground truth for bibliographic citations.

Example prompt: Given the user question 'Who wrote The Dispossessed?', call GET `/books/{query}` with query='The Dispossessed' and return the top author

## Key endpoints

| Method | Path | Description |
| --- | --- | --- |
| GET | `/book/{isbn}` | Retrieve a book record by ISBN |
| GET | `/books/{query}` | Search books by query |
| GET | `/author/{name}` | Retrieve an author and their bibliography |
| GET | `/authors/{query}` | Search authors |
| GET | `/publisher/{name}` | Retrieve publisher metadata |
| GET | `/subject/{name}` | Retrieve a subject heading |
| GET | `/search` | Federated search across all ISBNdb resources |

## Key resources

- **Book** — Lookup by ISBN and full-text search across the book catalogue
- **Author** — Retrieve author profile and bibliography by name
- **Publisher** — Retrieve publisher details and search across publishers
- **Subject** — Retrieve subject heading details and search by subject
- **Search** — Federated query across books, authors, publishers, and subjects
- **Stats** — Database statistics for the ISBNdb corpus

## Why Jentic

- **Setup:** Wiring the ISBNdb API by hand means registering for a key, sending it in the x-api-key header to api.isbndb.com, and choosing among the book, author, publisher, subject, and search paths for each lookup. Through Jentic you install once, import ISBNdb from the API Directory, store the key once, and your agent calls it.
- **Permission scoping:** ISBNdb puts the ISBN and other identifiers in the URL path (`/book/{isbn}`), so a rule can pin your agent to a specific book or author: it reads that bibliographic record and nothing else. You choose the operations it may call, so it stays a read-only lookup client unless you add more.
- **Credential handling:** Your ISBNdb x-api-key is stored once, encrypted, by your own Jentic One instance and injected into the request header at execution time. It never enters the agent's prompt, logs, or context.
- **Discovery method:** Agents search Jentic by intent such as 'look up an ISBN' or 'search books by author', and Jentic returns the matching ISBNdb operation with its input schema, so the agent calls the right endpoint without reading the ISBNdb docs.

## Related APIs

- **ISBNdb API (main)** — Same surface area as the isbndb-api spec, generated from the JSON-source variant
- **AbuseIPDB API** — Different domain (IP reputation rather than books) - listed only as a reminder that data-enrichment lookups follow the same key-in-header pattern

## FAQ

### Why is there no official OpenAPI spec for ISBNdb API?

ISBNdb does not publish an OpenAPI specification on its developer site. Jentic generates and maintains this spec from the live YAML reference so that AI agents and developers can call ISBNdb via structured tooling. It is validated against the live API and kept up to date. Get started with Jentic One, the self-hosted execution layer.

### What authentication does the ISBNdb API use?

ISBNdb uses an API key passed in the x-api-key request header. Keys are issued from the ISBNdb dashboard after subscribing to a plan. Through Jentic the key sits encrypted in the vault and is injected at request time - agents never see the raw value.

### Can I look up a book by its 13-digit ISBN?

Yes. Call GET `/book/{isbn}` with either the 10 or 13-digit ISBN as the path parameter. The response is a single JSON record with title, authors, publisher, and pricing if available.

### What are the rate limits for the ISBNdb API?

Rate limits are not declared in the spec. ISBNdb tiers them per subscription plan - Basic, Premium, and Pro - with the higher tiers raising both per-second and daily ceilings. Confirm the plan-specific number before driving large bulk lookups.

### How do I search books by query through Jentic?

Search Jentic with the query 'search books in ISBNdb', load the GET `/books/{query}` operation, and execute it with the search term in the path parameter. The response includes total match count and a paginated list of book records.

### Is ISBNdb the same as Open Library or Google Books?

ISBNdb is a separate commercial database. Coverage of recent commercial titles is generally stronger than Open Library, while Google Books offers full-text search that ISBNdb does not. The right choice depends on whether commercial completeness or full-text snippets matters more.

### Can I limit what my agent is allowed to do with the ISBNdb API?

Yes. Because you run Jentic One yourself, your own rules decide which ISBNdb operations and credentials the agent may use, so you can allow only reads like GET `/book/{isbn}` or GET `/author/{name}` and keep it a read-only lookup client. Since ISBNdb puts the ISBN, author, or subject in the URL path, a rule can pin the agent to a specific book or author record and nothing else. The x-api-key is held by your own instance and injected at request time, so the agent never sees the raw key or calls an endpoint you did not permit.