get_book

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare readOnlyHint=true, so description's burden is lower. Description adds useful error behavior (404 if not found) and optional parameter effect (edition_id resolves to specific edition). No contradictions.

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: first states purpose and return structure, second covers error behavior, third provides usage guidance with alternative. No filler, all information is essential and well-organized.

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 single-item retrieval tool, the description covers purpose, parameters, return structure (though no output schema, it lists fields), error case, and usage context. No gaps given the tool's complexity.

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%, baseline 3. Description adds value by explaining that book_id comes from search_books, and edition_id resolves to a specific edition with details (language, cover, ISBN). This goes beyond the schema's brief descriptions.

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?

Clearly states verb 'Get', resource 'full public metadata for a single book', and method 'by catalog UUID or slug'. Distinguishes from siblings like search_books (searching) and get_series (series info).

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 specifies when to use: 'you already have a book_id or slug and need details/editions'. Provides alternative: 'If you only have a title or author, call search_books first to obtain the id.'

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.