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

Annotations already declare non-read-only, idempotent, open-world and non-destructive, so the safety profile is covered. The description adds genuinely extra context: it creates two entities (account + first folder), requires verified signup and explicit terms acceptance, and clarifies the return contract by warning that no login credentials are returned because data access stays OAuth. That last point is the kind of information an agent cannot get from annotations.

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 short sentences, front-loaded with the action and resources, then prerequisites, then the return-value caveat. Nothing is redundant and each clause carries information, though the telegraphic 'Réutiliser le code de l’e-mail' fragment reads as a note rather than integrated guidance.

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 an 18-parameter, 15-required mutation with no output schema, the description covers the essentials of what is created, the precondition, and the credential-free response. It leaves notable gaps: the origin of signup_id (presumably start_account_signup), no error/failure behavior, and no coverage of the roughly half of parameters undocumented in the schema.

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 50% and there are 18 parameters, 15 required, so the schema carries much of the burden. The description does add real meaning for two otherwise opaque fields: 'code' is the e-mail code to be reused, and the terms sentence maps to accept_terms/terms_version. But the remaining undocumented business fields (name, city, street_address, business_location, etc.) receive no clarification beyond the schema.

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 concrete verb and two concrete resources: creating the new account plus the first dossier, with a precondition of verification and explicit terms acceptance. This is clearly distinguishable from start_account_signup and verify_account_signup, though it does not name those siblings 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 phrase 'après vérification et acceptation explicite des conditions' implies the ordering constraint (verify first, then complete), which is real usage guidance. However, it never names alternatives or exclusions, and does not point to get_account_signup_requirements for obtaining valid catalogue values, so the agent must infer the sequence.

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