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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=false, so safety is covered; the description still adds real value by disclosing the auth requirement, the 'les derniers' recency/limited scope, and the privacy trait that no client private data is exposed. It does not state a default result count or pagination behaviour, which is the remaining gap.

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 compact sentences with the audience/prerequisite stated first and the returned fields second. Every clause carries information (audience, auth, payload, privacy), with only minor density from the parenthetical.

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?

Because there is no output schema, enumerating the returned fields is valuable and largely covers the return shape. But for a 3-parameter tool with only 33% schema coverage, leaving 'limite' and 'statut' completely undocumented in both schema and description leaves an agent without enough to invoke it precisely.

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 only 33% — 'limite' and 'statut' have no schema documentation at all — and the description compensates for neither. Only a faint hint ('les derniers') gestures at 'limite'; nothing explains valid 'statut' values or how filtering interacts with mode.

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 — recent payments received (sales) for the authenticated Tchin user — and enumerates the returned fields (date, montant, net, moyen, statut, lien), so an agent can tell what it fetches. It stops short of a clean verb ('List…') and never differentiates itself from close siblings like rapport_ventes, mes_transactions or detail_paiement, which is what keeps it off a 5.

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?

It supplies a prerequisite (user must be connected to their Tchin account, connect on first use) which frames the usage context. But there is no explicit when-to-use/when-not, and no routing signal versus rapport_ventes (aggregate reporting) or mes_transactions (all movements), so the agent must infer selection.

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