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

Annotations already declare destructiveHint=true, idempotentHint=true and readOnlyHint=false, so the safety profile is known. The description adds useful context the annotations lack — login requirement on first use, and the 0 = montant libre convention — but it never explains what 'destructive' means here (overwrite vs. partial update) or whether omitted fields are preserved.

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 sentences, front-loaded with the actor/auth condition before the action. Dense but no filler; only the parenthetical about first-time login could be trimmed.

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 destructive, idempotent mutation with 6 params and no output schema, the description should state update semantics (partial vs. full replace) and what a successful call yields. It covers the field list and auth well but leaves those behavioral questions to inference.

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?

With schema coverage at only 33%, the description carries real weight: it maps out the modifiable surface (titre, montant, description, moyens, test/réel) and clarifies that montant=0 means free amount and that test toggles test vs. real mode. It does not clarify the moyens enum values or lien address/code formats beyond what the schema already says.

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 ('Modifie') and resource ('un lien de paiement ou un formulaire') and enumerates the mutable fields. It is clearly distinguishable from creer_lien_paiement, supprimer_lien and activer_lien by the verb alone, though no sibling is named explicitly.

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 first sentence gives caller context ('utilisateur connecté à son compte Tchin, marchand ou particulier') and an auth note, which implies this edits an already-existing link. But it never says when to prefer this over activer_lien or supprimer_lien, nor any exclusion or prerequisite beyond login.

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