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 covered structurally. The description adds genuine context beyond that: an authentication requirement on first connection and a default 30-day window with a fixed date format. It does not describe the response shape or any limits/aggregation caveats, so it adds moderate rather than rich behavioral context.

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?

Three sentences, front-loaded with the resource and the metrics, then scope and defaults. Dense but every sentence carries information; the capitalized VENTES is mild emphasis noise but not bloat.

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 carries the burden of describing return values and does so by listing the aggregates and the three breakdown dimensions, plus the default period. What remains unstated is whether periods return a single aggregate or a time series, which matters for an agent deciding how to interpret results.

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 100%, so the baseline is 3 and the schema already documents au, du and mode. The description earns the extra point by supplying behavior the schema omits: the AAAA-MM-JJ date format restated for both bounds and, more importantly, the default of the last 30 days when dates are not supplied.

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 (VENTES = paiements reçus) and enumerates exactly what the report contains: total encaissé, net reçu, counts of successful/failed payments, and breakdowns by method, country and link. It also delimits scope with 'les ventes seulement, sans les dépôts, retraits ni envois', which separates it from balance/transaction reports. It stops short of naming a specific sibling tool (e.g. mes_ventes vs bilan_compte) for the agent to choose against.

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?

Gives clear usage context: for the logged-in Tchin user, with login requested on first use, plus a default window of the last 30 days when dates are omitted. It explicitly excludes non-sales movements, telling the agent when not to reach for this tool. No explicit pointer to an alternative sibling for listing individual sales or for account balance.

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