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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds value by noting the returned details are 'compact' and 'curated', and that the url should be used for the canonical page, which informs the agent about the nature of the output and expected user action. No contradiction with annotations.

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 concise sentences with zero superfluous words. Every sentence serves a purpose: stating the action and providing guidance on using the result. The description is front-loaded with the primary purpose.

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?

Given the simplicity (1 required parameter, no nested objects, presence of output schema), the description is complete. It covers what the tool does, what the input is, and how to use the output (direct users to the url). No further explanation of return values is needed due to output schema.

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 the id parameter described as 'Route id returned by search or recommend_tours.' The tool description doesn't repeat that but indirectly reinforces it by mentioning the tool fetches 'one published hut-to-hut tour.' This adds contextual meaning beyond the schema, justifying a score above baseline 3.

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 tool fetches 'compact, curated details for one published hut-to-hut tour', using a specific verb and resource. It distinguishes from sibling tools (recommend_tours, search) which return lists or recommendations, while this returns details for a single tour.

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 that the returned 'url' is canonical and should be linked to users, providing clear post-invocation guidance. The input schema's parameter description explicitly ties the id to results from search or recommend_tours, indicating when to use this tool. Though it doesn't state when not to use, the context is sufficient.

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