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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered. The description usefully discloses the shape of the returned plan (distribution/writable flags, optimization state, route overrides), which matters because there is no output schema, but it says nothing about failure behavior such as an unknown plan id.

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 terse fragments, front-loaded with the returned field list and closed by the endpoint. Nothing is wasted, though the comma-run field enumeration is dense rather than elegant.

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-by-id tool with one fully documented parameter and no output schema, the enumerated return fields are the key missing piece and they are present. Only error/permission behavior is left unstated, which is a minor gap.

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 description coverage is 100% and the single plan_id parameter is documented in the schema with accepted id formats, so the schema carries the burden. The description adds no format or id-handling detail beyond that.

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 the resource (a single plan) and enumerates the fields it returns, with the endpoint GET /plans/{planId} pinning the operation. The word 'One' implicitly separates it from spoke_list_plans, though no sibling is named explicitly.

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?

No when-to-use guidance and no alternatives referenced. An agent must infer that this is the single-record lookup versus spoke_list_plans or spoke_list_plan_stops, and there is no mention of prerequisites such as a valid plan id or permissions.

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