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

Annotations already declare readOnlyHint=true, idempotentHint=true, destructiveHint=false and openWorldHint=false, so 'Lecture seule' merely restates them. The description adds a list of returned data points, but with an output schema present that content is largely duplicated rather than adding behavioral context such as freshness or cost of the call.

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 front-loaded sentence enumerating the payload, followed by the read-only note; no filler. The comma-separated enumeration is dense but each item earns its place.

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 zero-argument read tool with full annotation coverage and an output schema, the definition is sufficient to call it correctly. Only the absence of an explicit usage trigger keeps it from being complete.

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 is 4 and there is nothing the description needs to compensate for. It also implies the scope is the authenticated user only, which is a useful semantic hint for a param-free tool.

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 names a concrete resource — the user's plan plus conversion consumption, quota renewal date, MCP safety limits and a recommended plan — which is clearly distinct from the conversion-specific siblings. It never explicitly says 'get' or names an alternative, but the enumerated payload makes the tool's identity unambiguous.

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?

There is no explicit when-to-use statement, no prerequisites and no named alternative. Usage is only implied (check quota/plan before spending conversions), and 'Lecture seule' is the sole operational signal.

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