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

Annotations provide readOnlyHint=true, so safety is clear. The description adds behavioral context beyond annotations by noting the inclusion of nearby trails and breadcrumbs. It does not cover error conditions or authorization needs, but these are less critical for a read operation.

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?

One concise sentence covering purpose, identifiers, and additional data included. No wasted words.

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 simple get tool with one parameter and no output schema, the description adequately states the purpose, scope (public, verified), and included data (nearby trails, breadcrumbs). Could be slightly more complete with output format hints, but overall sufficient.

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 single parameter 'trail' has 0% schema coverage, but the description explains it can be an 'id or slug', providing meaning beyond the schema. It could be improved with format examples or constraints.

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 clearly states the verb 'Get' and the resource 'a single public, verified trail', with distinguishing details like 'by id or slug' and 'including nearby trails and breadcrumbs'. It effectively differentiates from sibling tools like trails.search.

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?

Usage context is implied: use this to retrieve a specific trail by identifier, while trails.search is for multiple results. However, no explicit when-to-use, when-not, or alternative guidance is provided.

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