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

Goes well beyond the destructiveHint=true annotation by naming which operations are destructive and how: merge is flagged 'irreversible' and deletes the source trip, travellers 'replaces the list', cancellations 'remove deletes them', and cover_photo/notes clearing are implied. This is exactly the kind of consequence disclosure an agent needs before a write.

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?

Front-loads the core field-update purpose in the first clause, then groups the complex modes after a 'Also:' marker. Dense and semicolon-heavy, but every clause carries distinct operational meaning; no filler sentences.

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 12-parameter mutation tool with nested objects and three destructive sub-modes, the description covers the risky paths and their consequences, and the presence of an output schema means return values need not be explained here. Nothing critical to correct invocation is missing.

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%, so the baseline is 3, but the description adds real meaning beyond the schema field docs: it explains merge semantics (folds in + deletes), that travellers replaces rather than appends, and the keep/remove distinction for cancellations. Not exhaustive on all 12 params, but materially above baseline.

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 (change/update) and resource (a trip), then enumerates exactly which fields it mutates and the three special modes it also supports. An agent can distinguish this from get_trip (read) and delete_items (delete) without opening a 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?

Gives clear conditions for the non-obvious modes: merge_from_trip_id folds a trip in and deletes it, cancellations settles email-flagged items, refresh_places re-derives places/drives. It does not explicitly name alternatives (e.g. 'use get_trip to read first' or 'use delete_items for items'), so it stops short of full when/when-not routing.

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