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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description adds behavior beyond that: it returns exactly one page and uses keyset paging where the previous reply's next_cursor is passed as start_cursor. It does not mention rate limits or auth requirements, so it is strong but not exhaustive.

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?

Four short clauses, front-loaded with the resource and its returned fields, then filters, then endpoint and paging. Every sentence carries distinct information with no filler or restated title.

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?

With no output schema, the description compensates by naming the returned fields and explaining the one-page/keyset paging model, which is the main thing an agent needs to iterate correctly. It leaves filter date-range semantics and sort interactions to the schema, which is acceptable given 100% schema coverage.

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 schema already documents all 12 parameters including format patterns and enum values. The description adds value by mapping the API-level next_cursor to the start_cursor input and by confirming which fields are filterable, which is cross-field information the schema alone does not convey.

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 (list parts, qualified as the 'inventory catalog'), and enumerates the returned fields (part number, manufacturer number, category, unit cost), which implicitly separates it from fleetio_list_part_stock and fleetio_get_part. It never names a sibling alternative explicitly, so it falls short of full sibling differentiation.

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 hints at usage by naming the filterable fields (part number, manufacturer part number, UPC), implying when to use each filter. However, it gives no when-to-use guidance relative to alternatives such as fleetio_get_part for a single record or fleetio_list_part_stock for stock levels, and lists no exclusions or prerequisites.

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