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

Annotations already declare readOnlyHint=false, idempotentHint=true and destructiveHint=false, so the safety profile is covered. The description adds no extra behavioral context (e.g. that omitted fields stay unchanged, that null clears a value, or any permission requirement) beyond what annotations and the schema already say.

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 can be changed, the second supplies the usage rationale. No filler or redundancy.

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 mutation tool with no output schema and solid annotation coverage, the description supplies purpose and usage rationale, and the nested 'data' object's partial-update contract lives in the schema. It is only slightly incomplete in not mentioning isReturnToHome among the changeable fields.

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%, so the schema already documents every parameter, including the null-to-clear semantics and the 'omitted fields are left as they are' contract. The description's field list mirrors three of the mutable fields but omits isReturnToHome, adding little beyond the schema. Baseline 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?

The description states a specific verb ('Change') plus the mutable fields (place name, arrival/departure dates, notes) of a named resource, which is more than a restatement of the title. It does not explicitly distinguish itself from the nearby update_destination_option / update_variant / update_event siblings, but the field list makes the scope unambiguous.

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?

It gives a concrete usage context ('once the dates firm up') and names an alternative workflow it replaces ('rather than deleting and re-adding the stop'). There is no explicit when-not guidance, but the routing signal is clear enough for an agent.

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