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

Annotations already declare read-only, idempotent, open-world behavior, so the bar is lower, and the description still adds real operational context: a 10000-result exposure cap plus 'continue with page.next_offset when present, otherwise narrow process_type'. That is a concrete pagination and narrowing strategy an agent could not infer from the annotations. It stops short of describing record shape, but the output schema covers that.

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 sentences, each load-bearing, with the core purpose front-loaded and pagination last. Slightly dense telegraphic phrasing ('Search exposes...') but no filler or repetition.

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 filtered list tool with a 100%-documented schema, an output schema, and safety annotations already in place, the description covers the remaining gaps an agent needs: what is returned, how to get detail, how to resolve codes, what filters are unavailable, and how to page past the cap.

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 limit, offset, language, and process_type are already fully documented, including the 100 effective maximum. The description reinforces process_type's dependency on the reference lookup and rules out filter parameters that do not exist, but adds no syntax or format detail beyond the schema. Baseline 3 is appropriate.

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 procedure references) and immediately scopes it: it returns references only, not titles/stages/participants. It explicitly names euparl_get_procedure as the tool that yields the richer record, so an agent can distinguish the two without opening either schema.

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 routing: use euparl_get_procedure with a returned procedure_id for detail, and euparl_list_reference topic procedure_types for valid codes. It also lists what this tool cannot do (no keyword, year, committee, or stage filter), which prevents wasted calls more effectively than a positive description alone.

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