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. The description adds a useful boundary ('Contains no prices') and hints that each corridor has a page, but says nothing about pagination or result size.

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 tight sentences: the first front-loads what is listed, the second covers the filter and the 'no prices' caveat. No filler or repetition.

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 listing tool with one optional parameter, no output schema, and full annotation coverage, the description supplies what an agent needs to select and call it. Only deeper return-shape detail (e.g. how many pages) is absent, which is minor here.

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 100% with a single optional parameter, so the baseline is 3. The description goes beyond the schema's terse 'Country or city to filter on' by giving concrete example values ('Mali', 'Bamako', 'Abidjan'), which clarifies accepted input format.

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 specific verb ('Lists') and resource ('West African road corridors GraceRoad serves') plus the accompanying data (typical cargo and vehicles, a page per corridor). It is clearly distinguishable from the sibling tools (request preparation, presentation), though it does not explicitly name them.

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 description explains how the optional filter works ('a country or city name') but never states when to use this tool versus the siblings graceroad_preparer_demande or graceroad_presentation. Usage is implied rather than guided.

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