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

Annotations already cover readOnly/idempotent/openWorld, but the description adds real context: the external Google confirmation step, the shape of the response (verdict, answers.address, place_id, bookable, next), and the persistence recommendation to save place_id per customer and pass extended_address for units. It stops short of enumerating verdict or `next` values, and mentions no rate limits or auth needs.

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-loaded with the purpose, and every sentence carries actionable information about inputs and outcomes. The second sentence is a dense, heavily parenthesized run-on that takes effort to parse, which costs it the top mark.

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?

With no output schema, the description carries the burden of describing returns and it names the key fields (verdict, answers.address, place_id, bookable, next) and how to act on two of them. It never defines the possible verdict or `next` values, so an agent still has to infer some response semantics.

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?

Top-level property description coverage is reported as 0%, so the description must compensate, and it does: it tells the agent the input can be one line, a field object, or a saved place_id, and that extended_address carries the unit. The rich oneOf schema already documents the three spellings, so the description mostly reinforces workflow rather than adding new syntax.

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 ('check the service address before booking') plus the scope that distinguishes it from siblings: a business that comes to the customer. An agent can tell this apart from book/find_times/get_booking 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?

Gives strong conditional routing downstream ('Book when `bookable` is true', 'when the verdict is `confirm`, read the corrected address to the customer first', '`next` says what to do otherwise') and instructs reusing a saved place_id on the next call. It does not state when *not* to call check_address or name a sibling as an explicit alternative, so it falls just short of a 5.

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