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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds that only relevant passages (not whole documents) are returned, which is useful, but says nothing about pagination via cursor or the token/passage caps.

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 sentences, zero waste, and the core behavior is front-loaded before the usage hint. Nothing to trim.

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?

An output schema exists, so return-value explanation isn't needed, and the read-only nature is covered by annotations. However, with five parameters and 20% schema coverage, the missing guidance on query semantics, cursor pagination, and token/passage limits leaves real gaps for correct invocation.

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 only 20% (just the id field). The description explains nothing about query, cursor, max_tokens, or max_passages, so an agent must infer pagination and budget behavior from bare numeric constraints. With low coverage, the description should compensate but does not.

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 and resource: return stored passages relevant to a question about one library item. The scoping to a single item is clear. It doesn't explicitly differentiate from the sibling search_article, which is the nearest competing tool.

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?

Gives explicit sequencing ('Use after list_library') and names the alternative behavior it replaces ('instead of reading a long book, PDF, email... from the beginning'). No exclusion criteria versus search_article or search_web are offered, but the when-to-use condition is clear.

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