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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered by structured data. The description adds only that the content is an operational manual to be consulted up front. It says nothing about the guide's length, whether it is static or versioned, or what sections come back, which is the main thing an agent would want to know before loading it.

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 short sentences with no filler, and the read-first instruction is placed where it will be seen. The domain list is somewhat listy and the repeated 'Outil' token reads as a template artifact rather than deliberate wording, which keeps it from a 5.

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 tool with no output schema, the description carries the burden of explaining what comes back, and here it only gestures at topic coverage without indicating structure, size, or whether the guide is authoritative for tool selection. It is adequate to know when to call it, but thin on what the agent gets.

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 the baseline of 4 applies; the schema has nothing to document and the description correctly implies a parameterless fetch. There is no misleading implication that arguments are needed.

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 identifies the tool as an operational manual ('Mode d'emploi opérationnel') and enumerates the domains it covers: sites, marketing, formations, intégrations, lots, vérifications, gestion des erreurs. That is a specific resource with a stated scope, and no sibling tool provides a comparable general guide. It loses a point because the phrasing is awkward and repetitive ('Outil' appearing twice) and because it is written in French while the surrounding toolset is English, which may slow recognition.

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 sentence 'Lire au début d'une tâche Outil' gives an explicit timing instruction: read this at the start of a task. That is genuine when-to-use guidance rather than implied usage. It stops short of naming alternatives or stating when not to call it (e.g., once the guide is already in context), so it is not a 5.

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