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

readOnlyHint=true already covers the safety profile, so the bar is lower. The description usefully adds that the tool is free of charge, but it says nothing about what the response contains (feature catalogue vs. live data) or its size, which is the main behavioral question for a discovery 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 sentence that leads with the verb and enumerates scope, with no filler. It is slightly padded by the vague qualifier 'réelles' and the trailing 'Gratuit.'

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?

With no parameters, no output schema, and an annotated read-only hint, the definition is nearly adequate. Still missing is a minimal indication of what the agent gets back (a list of capabilities) that would let it decide whether to call this before or after the sibling tools.

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 there is nothing for the description to disambiguate. Baseline of 4 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?

The verb 'Découvrir' and the resource 'fonctionnalités de Plugtrip' are stated, and the enumerated domains (recharge, pauses, trajet, logement, communauté, véhicules) hint at scope. However, 'fonctionnalités réelles' is vague about what the tool actually returns — a feature list, documentation, or a capability check — and it does not explicitly separate itself from the sibling search/context tools.

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 statement of when to call this instead of search_stations or station_context, nor any prerequisite or exclusion. 'Gratuit' signals cost but says nothing about selection conditions.

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