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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds the behavioral context that this returns the reader's own library with shelf categories and ratings, which is useful. It doesn't disclose pagination, ordering, or whether ratings are included by default, but for a read-only list tool the annotations carry the main burden.

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?

One sentence that front-loads the scope ('signed-in reader's own Siftivo library') and packs in the shelf categories and ratings. No wasted words; every element earns its place.

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 read-only list tool with one optional parameter and no output schema, the description is nearly complete. It tells the agent what the tool returns and the scope. It could mention that the status filter maps to the shelf categories, but the schema already documents that. The absence of an output schema is acceptable since the description names the content (books, ratings, shelf status).

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 100% and the single parameter has a clear enum and description ('Filter to one shelf. Omit for the whole library.'). The description's mention of shelf categories aligns with the enum values, but it doesn't add meaning beyond what the schema already provides. Baseline 3 is appropriate.

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 clearly states the tool returns the signed-in reader's own Siftivo library, enumerating the shelf categories (want to read, reading, finished, set down) and ratings. This distinguishes it from sibling tools like get_my_book and get_reading_index by scoping it to the reader's personal library collection.

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 implies this is for the signed-in reader's own library, which differentiates it from get_book, get_author, and search_books. It doesn't explicitly name alternatives or state when not to use it, but the 'signed-in reader's own' phrasing provides clear context that this is personal-scope, not general catalog access.

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