get_book_spine

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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description's 'Read' is consistent with that. The description does not add behavioral context beyond the object being read, but no extra caveats are necessary for a simple read-only lookup.

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 six-word sentence with no filler; the action, resource, and result object are all present. It is optimally front-loaded and easy to scan.

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, read-only tool with an output schema and read-only annotations, the description is largely sufficient to support correct invocation. However, it is terse enough that an agent receives no context about what a 'spine' contains or how this relates to book pages, leaving a small gap in completeness.

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 only parameter, book_id, is fully described in the schema with type and a short description, so schema coverage is 100%. The description adds no parameter-level detail, but none is needed beyond identifying the book.

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 concrete verb ('Read') and a precise object ('a book's chapter and page structure'), making clear it returns structural metadata rather than page content. This distinguishes it from sibling tools like get_book_page, which reads a single page's content.

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?

No explicit when-to-use or when-not-to-use guidance is given; there is no mention of alternatives such as get_book_page or list_books. The intended use is only implied by the phrase 'chapter and page structure,' so the agent must infer when this tool is the right choice.

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