update_book

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

With no annotations provided, the description carries the full disclosure burden. It does add useful behavioral context with 'Only provided fields are updated,' clarifying partial-update semantics. However, it omits behaviors like what happens when book_id does not exist, whether copy-count fields have invariants (e.g., available_copies cannot exceed total_copies), or any error responses.

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 front-loaded sentences with no filler. The first sentence names the action and resource, and the second adds the critical partial-update behavior. Every word contributes.

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 output schema exists, so return-value explanation is not required. Still, with 7 parameters, no parameter descriptions, and no annotations, the description is too thin to fully guide correct usage; it leaves relationships between copy counts and field-specific semantics to inference.

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%, so the description must compensate, but it only groups fields vaguely as 'metadata or copy count' and names only book_id. It does not explain the meaning or constraints of fields like total_copies versus available_copies, nor does it detail how 'only provided fields' are passed in practice.

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?

States a specific verb ('Updates'), a clear resource ('book metadata or copy count'), and the key identifier ('by book ID'). This differentiates update_book from siblings like add_book, get_book, and delete_book 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 makes clear that this tool is for modifying an existing book identified by book_id, which implies usage for updates rather than creation/retrieval. However, it does not explicitly state when-not-to-use it, nor does it name alternatives such as add_book for new books.

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