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

Annotations already declare readOnly, idempotent, non-destructive, open-world, so the safety profile is covered. The description adds real value beyond that: it discloses that verification comes from Google, names the response fields (verdict, answers.address, place_id, bookable, next), and instructs the agent to persist place_id per customer. It stops short of describing failure modes or latency.

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, then send formats, then answer semantics and decision rules — every sentence earns its place. It is dense and leans on backticked tokens, which is efficient but slightly harder to scan than plain prose.

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?

There is no output schema, so the description carries the full burden of explaining the return — and it does, covering verdict, answers.address, place_id, bookable and next, plus what to do with each. For a single-parameter read tool this is complete.

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?

The nested schema is already detailed, but the description adds operational framing: three interchangeable send formats (one line, fields, or a saved place_id) and the instruction to save and reuse place_id 'for this customer'. It does not add field-level meaning beyond the schema's own naming rules.

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 concrete verb+resource ('Check the dog's address') with the exact value to the business ('its home, or where the dog is picked up'), and positions it in the booking flow. An agent can tell this apart from sibling 'book' without opening either 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 scoped to 'before booking' and gives decision rules: 'Book when bookable is true; when the verdict is confirm, read the corrected address to the customer first. next says what to do otherwise.' This is when-to-use, when-not-to-act, and fallback routing in one place.

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