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

With destructiveHint=true already declared, the description earns credit for disclosing a non-annotation behavioral trait: changes may propagate to the trip owner's connected calendars when automatic sync is enabled. It also states the edit-permission requirement. It stops short of covering partial-update semantics or reversibility.

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, front-loaded with the mutating action and its scope, then the side effect. Nothing is wasted, though the second sentence could be fused more compactly.

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?

Without an output schema, the description should ideally say what comes back and whether this is a partial or full update. It covers permission and calendar-sync side effects but leaves the update semantics (can a single field be changed? does omitting a field clear it?) and return behavior to inference.

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 schema itself explains the tricky conditional parameters (destination_scope and destination_confirmed). The description only restates the field list already present in the schema, adding no format, aliasing, or conditional detail. Baseline 3 is appropriate.

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 (Update) and resource (trip) plus the exact field families affected: dates, title, destination, description. However, it does not distinguish itself from the sibling trip_rename, which appears to overlap on the title-editing surface, so an agent must guess which tool to pick for a rename.

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 phrase 'for a trip the authenticated user can edit' gives a real precondition (edit permission) that narrows usage. But there is no when-not guidance and no mention of the alternative trip_rename or the more targeted trip_city_update / trip_cover_update siblings, so routing is only implied.

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