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

Annotations already declare the write/non-idempotent/non-destructive safety profile, so the bar is lower; the description adds genuinely useful context that the trip is created *empty* and that it is the parent container for all downstream items. It does not mention auth requirements, rate limits, or what is returned, but covers the key behavioral trait beyond 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?

Three sentences, front-loaded with the core purpose followed by the workflow and a practical tip; every sentence earns its place. Slightly long but 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 creation mutation with no output schema, the description conveys what gets created and how it fits the workflow, but it never states what the call returns or that the returned trip identifier is required for the next step (create_variant). That chaining detail is the main omission.

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 the schema already documents both name and coverPhoto with its own constraints, so the description need not carry parameter detail. The only added value is the operational note to ask the user for a name if absent, which is marginal — 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 (create) and resource (trip) and immediately frames it as 'the container everything else hangs off,' which distinguishes it from the add_*/update_* siblings that operate on an existing trip. An agent can tell this is the root creation step without opening the schema.

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?

Explicitly positions the tool as 'step 1 of planning' and sequences it against concrete siblings (create_variant, add_destination, accommodation/transport/event options), so the when-to-use is clear. It stops short of naming when NOT to use it (e.g. update_trip for existing trips, duplicate_variant), so it is not fully exhaustive.

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