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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint, so the safety profile is covered. The description adds a genuine behavioral detail — the minimum candidate threshold that governs whether a school is ranked — but does not describe sort order behavior, pagination, or how ties/limits interact.

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?

Two sentences, front-loaded with the resource and scope, dense but free of filler. Every clause carries information (types, geography, output fields, eligibility threshold), though the length of the first sentence slightly taxes readability.

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 usefully enumerates the returned fields (rank, name, commune, score, success rate, mentions). For a 5-parameter tool with only 40% schema coverage, however, it leaves limit and sector unexplained and offers no interaction details, so it is adequate but not complete.

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 40%: code_insee and department carry descriptions, while type, limit and sector do not. The description partly compensates by glossing each type value (collèges/brevet, lycées/bac, lycées pro/bac pro) and by naming the three geographic scopes, which hints at the code_insee vs department distinction. It adds nothing for limit or sector.

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 states a specific resource (school rankings) and enumerates the three school types it covers, mapping each to the exam it corresponds to (brevet, bac, bac pro). It also specifies the geographic levels. However, it never references the sibling tools (get_french_school, get_french_commune_schools, get_french_school_sectors), so the agent must infer differentiation on its own.

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?

Usage is implied through the scoping options (France, department, commune) and the eligibility threshold (40 candidates for France, 20 elsewhere), which helps the agent judge what will return results. But there is no explicit when-to-use vs when-not, and no routing to the sibling tools that return individual school or sector data.

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