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

No annotations are provided, so the description carries the disclosure burden. It states the tool reflects the authenticated user's own subscription, which implies auth scoping, and 'le cas échéant' discloses it may return an empty/absent result. However, it does not address what happens if no subscription exists or the response shape. Adequate but not rich.

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?

A single efficient sentence that front-loads the resource and scoping. Nothing to trim.

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 read-only getter with no annotations and no output schema, the description covers the core intent and scope, but leaves open what a null result means and how to authenticate. Minimum viable.

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?

There is one parameter and schema description coverage is 0%, so the description should compensate. It implies authentication by referring to 'l'utilisateur authentifié', which indirectly explains the auth_token requirement, but adds no format or acquisition details for the token.

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 states a specific verb and resource: it returns the active Iddet Plus subscription for the authenticated user. It is distinguishable from siblings like mcp_list_subscriptions (plural listing) and mcp_cancel_subscription (mutation), though the distinction is implicit rather than spelled out.

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?

No guidance on when to use this tool versus mcp_list_subscriptions or mcp_grant_subscription. The 'le cas échéant' (if any) hints it may return nothing, but there is no explicit when/when-not context.

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