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

Annotations already declare readOnly, open-world and non-destructive behavior, so the safety profile is covered. The description adds genuinely useful context beyond them: the exact billing cost ($0.003 per request) and the breadth of returned data, though it omits any rate-limit or error/empty-result behavior.

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?

Purpose is front-loaded, followed by the return inventory and then the billing note, so nothing critical is buried. The long enumerated return list is dense but each item is relevant given there is no output schema.

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 properly carries the return-value burden by enumerating the fields returned, and it adds a cost signal. It is complete enough to call correctly, though it never states auth/API-key requirements or the shape of error responses.

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 meaning for the required parameter by disclosing its origin (from search_places). The optional country/language flags are left to the schema and get no extra explanation in the text.

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 ("Get a Google Maps place by place_id") and immediately disambiguates from its siblings place_photos, place_reviews and search_places by naming the upstream source of the id. An agent can tell exactly what this returns 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?

The parenthetical "(from search_places)" tells the agent where the required place_id must come from, effectively instructing it to search first. However, it does not explicitly say when to prefer this over place_photos or place_reviews, so a small inference gap remains.

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