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

Annotations already declare readOnly, idempotent, non-destructive, and non-open-world behavior, so the safety profile is covered. The description adds useful context beyond that: the score is an estimate out of 990 and no account is needed. It does not say how many links come back, whether they point to external URLs (relevant given openWorldHint=false), or what the output looks like.

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?

One front-loaded sentence names the action first and then enumerates the three resource types with only the qualifiers that matter ('990', 'sans compte'). Nothing is redundant and nothing is missing that belongs in a short link-listing tool.

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 zero-parameter, read-only link tool with annotations covering safety and no output schema, the description supplies the domain context an agent needs to pick it. The only gap is the return shape — number of links and whether they are external URLs — which matters slightly given the non-open-world hint.

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 tool takes zero parameters, so there is no parameter meaning to add; baseline 4 applies. The description appropriately spends no words on inputs and instead describes the returned content.

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 concrete verb ('Donne les liens') and names the three resources returned: the free TOEIC test, the CEFR level test, and free exercises. It implicitly separates itself from score_toeic by framing the output as links rather than a score, but it never names a sibling explicitly, so differentiation is inferred rather than 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?

Usage is implied by the qualifiers 'gratuit' and 'sans compte' — call this when a user wants free, no-signup assessment links. There is no explicit when-to-use or when-not-to-use statement and no routing against score_toeic or guides_toeic, which share the same TOEIC domain.

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