List library items

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

With the readOnlyHint annotation already indicating the tool is safe (no destructive side effects), the description adds valuable behavioral context by listing filter groups and explaining the detail parameter's projection behavior. However, it does not mention rate limits or the 0-based page number convention, which would be useful.

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 3 sentences long, which is reasonably concise. The second sentence about using get_library_filter_data is valuable but slightly front-loads a niche instruction. The list of filter groups is dense and could be better separated into a structured list for readability, but it does convey essential 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?

For a 9-parameter tool with no output schema, the description covers the main nuances: pagination, sorting, filter types, and the two detail levels. It is mostly complete for effective invocation, though it omits explanation of how page is 0-based and what the 'random' sort value implies. The absence of output schema is compensated by the detail parameter description.

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 coverage is 100%, so the baseline is 3. The description goes beyond by grouping filter parameters into 'valued' vs 'standalone', clarifying that filter_value must be omitted for standalone groups. This adds practical meaning to the enum definitions. A small deduction because the description doesn't explain all param relationships (e.g., how collapse_series interacts with sorting).

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 uses the specific verb 'Lists' targeting 'items (books or podcasts) of a library', clearly differentiating it from sibling tools like 'list_libraries', 'list_series', and 'list_authors' that list other entities. The pagination, sorting, and filtering capabilities are explicitly stated.

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 tells agents to 'use get_library_filter_data first to learn the valid filter values', providing a clear prerequisite. It distinguishes between 'valued' and 'standalone' filter groups, guiding correct parameter usage and preventing invocation mistakes.

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