Google Library Agent API
Browse all Google APIs38
AI ReadinessNon-Ready (F)38/100
Official vendor OpenAPI document · agent-readyEducationLmsoauth25 EndpointsREST
For Agents
Browse shelves and books and simulate borrow and return actions on a sample Google library service. Useful as a learning aid and integration test target.
Use for: List all shelves in the library agent service, Get the details of a specific book, I want to borrow a book by resource name, Return a book that was previously borrowed
Not supported: Does not represent a real library catalog, support creating shelves or books, or persist user-specific state - use only as a sample for learning Google's API patterns or for integration tests.
The Library Agent API is Google's example library service exposing a small set of operations over shelves and books, intended for developers to learn the Google Cloud APIs design patterns. It supports listing shelves, listing or fetching individual books, and modeling borrow and return actions on a book. Because it is a sample API rather than a production service, it is most useful as a teaching tool, an integration test target, or a reference for Google's resource-oriented API conventions.
Install Jentic One Beta
Connect the Library Agent API to your agent
Jentic One is a self-hosted execution layer for AI agents. It lets your agent call the Library Agent API, or any other public or private API you need. You set the rules, the agent never sees your credentials, and every call is logged.
Two steps, two machines. Install the instance in a safe environment, then register your agent from wherever it runs.
1
Step 1: Jentic One Host machine
# On the machine that will host your Jentic One instance:
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fgoogleapis.com%2Flibraryagent" | sh2
Step 2: Agent machine
# On the machine where your agent runs (keep this separate from the instance):
curl -fsSL "https://jentic.com/install.sh?src=apis&api=%2Fapis%2Fgoogleapis.com%2Flibraryagent" | sh
jentic register # connects your agent to your Jentic One instanceJentic One is in public beta. The setup above keeps your agent separate from the instance, which is what you want before using real credentials: an agent running as the same OS user as Jentic One can read its stored keys directly. Just evaluating? A single local install is fine to start. See the secure deployment guide for the tiers.
Capabilities
What an agent can do with Library Agent API.
List shelves available in the library service
List the books on a specific shelf
Fetch a single book by its resource name
Borrow a book using the books:borrow action
Return a borrowed book using the books:return action
Use Cases
Patterns agents use Library Agent API for, with concrete tasks.
★ Learning Google Cloud API design patterns
Developers exploring Google Cloud's resource-oriented API conventions use the Library Agent API to see hierarchical resource names like shelves/{shelf}/books/{book} and custom verb actions such as :borrow and :return in practice. The endpoints are stable and free to call, which makes the service a low-stakes sandbox for new SDK and tooling work.
List shelves with GET /v1/shelves, then list books on the first shelf and fetch one book by resource name.
Integration test target for SDKs and agents
Teams building SDKs, MCP servers, or agent frameworks need a real Google API target for end-to-end tests that does not risk production data. The Library Agent's borrow and return endpoints provide simple state changes that an integration suite can call safely on every CI run.
Borrow a book then return it and assert that the response state transitions correctly.
Demo data for educational tutorials
Workshops and onboarding sessions for Google Cloud APIs use the Library Agent service as the backing store for live coding demos. The shelves and books domain is intuitive enough that learners can focus on auth, pagination, and request shape rather than learning a complex service.
Walk a learner through GET /v1/shelves, GET /v1/{+parent}/books, and POST /v1/{+name}:borrow with explanations for each call.
Agent framework smoke tests through Jentic
An agent framework can use the Library Agent API through Jentic as a smoke test that validates the full search-load-execute flow without needing real customer credentials. The five operations cover list, get, and custom-verb actions, which exercises the most common Jentic discovery paths.
Run google_libraryagent_borrow_book with a known book resource name and verify the response includes state=BORROWED.
Key Endpoints
5 endpoints — the library agent api is google's example library service exposing a small set of operations over shelves and books, intended for developers to learn the google cloud apis design patterns.
METHOD
PATH
DESCRIPTION
GET
/v1/shelves
List all shelves
GET
/v1/{+parent}/books
List books on a shelf
GET
/v1/{+name}
Get a single book by resource name
POST
/v1/{+name}:borrow
Borrow a book
POST
/v1/{+name}:return
Return a borrowed book
GET
/v1/shelves
List all shelves
GET
/v1/{+parent}/books
List books on a shelf
GET
/v1/{+name}
Get a single book by resource name
POST
/v1/{+name}:borrow
Borrow a book
POST
/v1/{+name}:return
Return a borrowed book
Jentic AI Readiness Score
This API is usable in Jentic One now. Its AI-readiness score against Jentic's framework shows where it stands today and where improvements would make it even easier for agents to use.
L
Library Agent API
- Non-Ready (F)38/100
72
Foundational Compliance56
Developer Experience & Jentic Compatibility16
AI-Readiness & Agent Experience94
Agent Usability63
Security63
AI DiscoverabilityPowered by JenticScoring Framework 1.0.0 | Scoring Engine 0.4.0
Show dimension breakdown
72
Foundational Compliance
Base layer of spec validity and structural soundness.
Grade: A-Signals: 4
89%
Lint Results
Aggregated quality score from linter diagnostics, weighted by severity.
100%
Resolution Completeness
Percentage of `$ref` references that resolve successfully.
0%
Specification Validity
Checks whether the API description parses successfully and conforms to its declared specification (e.g., OpenAPI).
100%
Structural Integrity
Structural correctness score based on schema issues using logarithmic dampening.
56
Developer Experience & Jentic Compatibility
Clarity, completeness, and ingestion readiness for developers and tooling.
Grade: CSignals: 4
0%
Example Density
How richly the API is illustrated with examples.
100%
Example Validity
Percentage of examples that conform to their schemas.
25%
Response Coverage
Percentage of operations with complete response definitions (success, client error, server error).
100%
Tooling Readiness
Health of API ingestion, bundling, and resolution within Jentic pipelines.
16
AI-Readiness & Agent Experience
Semantic breadth, depth, and agent comprehension for AI systems.
Grade: FSignals: 4
63%
Description Coverage
Coverage of descriptions across API elements.
0%
Error Standardization
Coverage of RFC 9457 Problem Details for error responses.
0%
OperationId Quality
Coverage, uniqueness, and casing consistency of operationIds for AI inference.
0%
Summary Coverage
Coverage of summaries across operations/tags/info.
94
Agent Usability
Functional utility, complexity comfort, and AI orchestration readiness.
Grade: A+Signals: 1
94%
Complexity Comfort
Agent comfort level based on API operational and structural complexity.
63
Security
Trust, risk posture, and security compliance.
Grade: B-Signals: 1
62%
Authentication Strength
Average quality of security schemes based on authentication method strength (weakest link for OAuth2).
63
AI Discoverability
Findability, semantic richness, and reasoning readiness.
Grade: B-Signals: 1
62%
Descriptive Richness
Clarity and depth of descriptions across API elements.
Score it yourself
Every API in the directory is allowlisted, so you can re-score it with no key required.
npx @jentic/api-scorecard-cli score <openapi-url>Why Jentic?
What agents get from Jentic-routed access to this vendor.
Setup
Wiring the Library Agent API by hand means configuring service-account or user OAuth2, refreshing tokens, and learning its shelf and book resource-name paths yourself. Through Jentic you install once, import the Library Agent API from the API Directory, store the credential once, and your agent calls it.
Permission scoping
The shelf and book names travel in the URL path (/v1/{parent}/books, /v1/{name}:borrow), so a rule can pin your agent to one shelf: it lists and borrows books under that shelf and nothing else. You choose the operations it may call, so if you grant only the list and get operations the agent can browse without borrowing or returning.
Credential isolation
Your Google Cloud service-account or user OAuth credential is stored once, encrypted, by your own Jentic One instance and injected at execution time as a short-lived access token. The raw secret never enters the agent's prompt, logs, or context.
Intent-based discovery
Agents search Jentic by intent such as 'list shelves' or 'borrow a book', and Jentic returns the matching v1 operation with its resource-name template so the agent calls the right endpoint without browsing the reference docs.
Related APIs
Alternatives and complements available in the Jentic catalogue.
FAQs
Specific to using Library Agent API through Jentic.
What authentication does the Library Agent API use?
OAuth 2.0 with the https://www.googleapis.com/auth/cloud-platform scope, using a standard Google Cloud service account or user OAuth flow. Through Jentic the credential lives in the encrypted vault and the agent only ever sees a short-lived access token.
Is the Library Agent API a production service?
No. It is a Google sample API, designed to demonstrate Cloud API design patterns and serve as a learning and integration test target. Do not build production workflows on top of it; the data is shared and the service has no SLA.
What are the rate limits for the Library Agent API?
Google applies the default Cloud APIs project quota of 60 requests per minute. The service has no published per-endpoint limits because it is a sample, but standard 429 backoff still applies.
How do I borrow a book through Jentic?
Run jentic search 'borrow a book in the library agent service' to find POST /v1/{+name}:borrow, jentic load to fetch its parameters, then jentic execute with the book resource name like shelves/123/books/456. The response includes the new state field.
Can I create new shelves or books with this API?
No. The Library Agent v1 API only exposes list, get, borrow, and return. Shelves and books are seeded by Google and cannot be created or deleted through the API.
Is the Library Agent API free?
Yes. The service has no per-call pricing - only the standard Google Cloud project quota applies.
Can I limit what my agent is allowed to do with the Library Agent API?
Yes. Because you run Jentic One yourself, your own rules decide which operations and credentials your agent may use with the Library Agent API. Since shelf and book names travel in the URL path, you can pin the agent to a single shelf so it only lists and borrows books under that shelf and nothing else. You also choose the operations it may call, so granting only the list and get operations lets the agent browse without ever borrowing or returning a book.
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