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. Beyond that, the description adds genuinely new behavioral context: the tool requires an authenticated session (prompting login on first use) and enumerates the exact data surface returned (name, Tchin ID, country, KYC, PIN status, per-country balances, crypto, cashback) – valuable given there is no output schema.

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 audience/context and then the returned fields. The second sentence is a dense fragment list, but every item maps to real returned data rather than filler.

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 parameterless, read-only tool with no output schema, the description compensates well by enumerating the returned fields and noting the login requirement. It stops short of stating failure behavior when no session exists or how the two account types differ in what is returned.

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?

The tool takes zero parameters, so the baseline of 4 applies. The description adds no parameter-level information, but none is needed or possible for a parameterless call.

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 identifies the resource (the connected user's Tchin account, merchant or individual) and enumerates the fields it exposes, but never states an explicit verb such as 'retrieve' or 'view'. It also fails to distinguish itself from closely related siblings like bilan_compte, mon_cashback, or mon_parrainage, which an agent must differentiate on its own.

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?

'Pour l'utilisateur connecté à son compte Tchin' implies the usage condition (an authenticated session) and parenthetically notes that connection is requested the first time. However, no alternative tool is named and no when-not-to-use guidance is given, leaving routing between account-related siblings to inference.

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