library_stats

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

With no annotations provided, the description carries the full burden. It clearly indicates a read-only reporting action ('Report totals') and specifies the outputs (item counts, collection count). Although it doesn't discuss performance or edge cases, the presence of an output schema reduces the need to describe return values. The behavior is adequately transparent for a simple stats 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 a single, concise sentence that front-loads the verb ('Report') and provides a clear scope with a colon-separated detail. Every word earns its place; there is no redundant information.

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 low complexity (no parameters), the description is nearly complete. It states what is counted (items and collections) and the output schema covers return values. However, it does not provide context about the scope ('the library') or how this compares to sibling tools, which might be useful but is not critical for such a simple 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?

The input schema is empty (0 parameters), so the baseline is 4. The description does not need to explain any parameters, and it adds no param-specific information because none exist. No additional meaning is required beyond what the schema already trivially covers.

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's function: 'Report totals for the library' and specifies what totals (item counts and collection count). This distinguishes it from sibling tools that focus on individual items, searches, or collections.

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?

No explicit guidance on when to use this tool versus alternatives. The intended use is implied by the nature of the tool (aggregate stats), but there is no direct comparison or prerequisite mentioned. It would benefit from a note like 'Use instead of list_collections when you need summary counts.'

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