library_stats

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

No annotations are provided, so the description bears full burden. It discloses the return structure but does not explicitly state that the tool is read-only or safe, nor any potential side effects. Given the nature of a stats tool, it is likely safe, but the description lacks this explicit assurance.

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 extremely concise, using two short sentences. The first states the purpose, the second lists the return fields. No extraneous words, well-structured.

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's simplicity (no parameters, read-only stats), the description is fairly complete. It lists the return fields and implies non-destructive behavior. However, it could mention whether the stats reflect a snapshot or are live, and if any performance impact exists. Minor gaps.

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?

Tool has zero parameters, so schema coverage is 100%. The description adds no parameter information, which is acceptable since none are needed. Baseline score of 4 is appropriate for a parameterless tool.

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 gets statistics about the local paper library, listing the specific fields returned. It is distinct from sibling tools like library_search or search_papers, which focus on querying papers rather than aggregate stats.

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 usage for statistics, but provides no explicit guidance on when to use this tool vs alternatives, nor any prerequisites or conditions. The agent must infer its role from the tool name and purpose.

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