messagerie_dossiers

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds genuinely useful context beyond them: the result is hierarchical ('arborescence') and carries unread counts per folder. It does not discuss ordering, depth, or empty trees, but with annotations present this is adequate.

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?

A single parenthetical sentence that front-loads the resource and then lists the returned fields. No padding, though it is terse enough to leave some questions open.

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 parameterless read-only listing with annotations covering safety and no output schema, the description states what is returned clearly enough to invoke correctly. The absence of an output schema is a minor gap given the fields are already enumerated.

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 is 4. There is nothing for the description to compensate for, and it correctly implies the tool returns all folders without filtering.

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 names a specific resource - the personal mail folder tree - and enumerates its payload (identifiers, names, unread counts). That distinguishes it from siblings like messagerie_creer_dossier (creates a folder) or messagerie_lister (lists messages). It lacks an explicit verb, but the noun-and-contents phrasing makes the read/list intent unambiguous.

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?

There is no statement of when to call this versus alternatives. Siblings such as messagerie_non_lus or messagerie_lister are never referenced, and no prerequisite or context is given. Usage must be inferred purely from the resource it describes.

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