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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), and the description usefully adds pagination (next_cursor), an exact total, and full-text output. However, its claim that the default shows 'only those still pending' conflicts with the schema's stated default (pending AND failed of the last 7 days), introducing confusion about actual behavior.

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?

Front-loaded with the action, then scope, default, and pagination in a compact set of clauses. The 'AFFICHE UN ÉCRAN' parenthetical is slightly odd but harmless; overall dense with little waste.

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 read-only list tool with full schema coverage and rich annotations, the description covers scope, default filtering, and pagination/total. The one gap is the default-filter discrepancy noted above; otherwise nothing essential to invocation is missing.

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 description coverage is 100%, so all four parameters are already documented in the schema. The description echoes pagination (next_cursor) and scoping (conversation) but adds no format or semantics beyond what the schema provides; baseline 3 applies.

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 (List) and resource (scheduled messages), and clarifies scope as organization-wide or a single conversation. It is distinguishable from siblings like ficiel_schedule_message (create) and ficiel_cancel_scheduled (mutate), though it does not name those alternatives directly.

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?

Provides an implied default ('Par défaut, seulement ceux encore en attente') but offers no explicit when-to-use / when-not-to-use guidance and never names an alternative tool. Adequate but leaves routing to inference.

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