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

With no annotations, the description carries the full behavioral burden. "Vérifier" implies a read-only lookup, but nothing is said about what happens when the session ID is invalid or unpaid, whether the call has any side effects, or what status values can come back.

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 short sentences, front-loaded with the core action, no filler. The second sentence is mild restatement but earns some place as the only usage hint.

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?

No output schema exists, so the description should say what a "statut" looks like (paid, pending, expired) and how failures surface. It covers neither, and with no annotations either, an agent has little beyond the name to reason about 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% and the parameter description already explains that sessionId comes from create_checkout. The description's "par son ID de session" is redundant with the schema, so 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 and resource: verifies the status of a Stripe payment by session ID. This clearly separates it from create_checkout in spirit, but the description itself never names that sibling – the connection only appears in the schema's parameter description.

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?

"Utile pour confirmer si un utilisateur a finalisé son paiement" gives an implied usage context (post-checkout confirmation) but no explicit when/when-not rules, no prerequisites, and no mention of create_checkout as the upstream step. An agent must infer the workflow.

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