search_my_library

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

Annotations already declare readOnlyHint=true and openWorldHint=true, which lower the bar. The description adds useful behavioral context: return format as '{ count, books[] } with status and rating', and the authentication requirement (SANSFICTION_TOKEN and documentation link). While it does not describe edge cases like empty results or rate limits, it adequately supplements the annotations for a read-only search tool.

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?

The description is four sentences, each adding distinct value: action/scope, return format, usage guidance, and authentication. It is front-loaded with the core purpose. While efficient, it could be compressed slightly (e.g., merging the usage sentence with the alternative tools). Still, it avoids redundancy and earns a 4.

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?

Given the tool has 3 parameters, no output schema, and low complexity, the description covers the essential aspects: scope, return shape, usage guidelines, and auth. It does not mention pagination or sorting, but those are documented in the schema (limit parameter). Overall, it is complete for a focused search tool.

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%, so the baseline is 3. The description does not add any parameter-specific meaning beyond what the schema already provides (e.g., query matches titles/subtitles is already in schema). The schema's descriptions for 'limit', 'query', and 'status' are sufficient, and the tool description offers no extra semantics for individual parameters.

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 it is a 'full-text search restricted to the user's own library' targeting book titles and subtitles, which distinguishes it from sibling tools like 'search_books' (catalog-wide) and 'list_my_books' (listing all). However, the phrase 'full-text search' is slightly misleading because it only matches title and subtitle, not the full content. This minor imprecision prevents a perfect score.

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 explicitly states 'When to use: find a specific book the user already owns' and contrasts with 'search_books' for catalog-wide discovery and 'list_my_books' for listing all shelves. It also mentions the required authentication token, providing clear when-to-use, when-not-to-use, and alternative tools. Excellent guidance.

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