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

Annotations already declare destructiveHint=false and idempotentHint=true, so the safety profile is partly covered. The description adds real value beyond that: it clarifies that stopping is a reversible hide ('can be restored by saving it again'), that no claims or bookings are affected, and that sign-in to Untap is required. This is meaningful behavioral context an agent could not read from the annotations alone.

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?

Four short, front-loaded sentences with no filler. The most important point (it is a hide, not a delete) comes first, followed by restoration, side-effect scope, and auth.

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 single-parameter mutation with no output schema, the description covers everything needed to invoke safely: reversibility, absence of side effects on claims/bookings, and the authentication requirement. No material gap remains.

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% and there is only one parameter, whose schema description already explains retention and restoration. The description repeats the commute_id restoration behavior but adds no syntax or format detail beyond the schema, so the baseline of 3 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?

States a specific verb and resource: 'Hides a saved train route from the active list.' The word 'hides' precisely distinguishes this from a deletion, and the follow-up sentence confirms the route is retained. It does not explicitly name a sibling it complements, so it falls short of full sibling differentiation.

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 is implied rather than stated: the agent can infer this pauses a commute rather than removing it, and that re-saving with the same commute_id restores it. There is no explicit when-to-use versus when-not-to-use framing or named alternative among the many commute siblings (list_commutes, save_commute, check_commute).

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