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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds useful scope context: it clarifies that photo and review data are NOT returned here but live in sibling tools, which prevents over-expecting the payload. It does not add pagination or auth detail, but that is minor with output schema present.

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?

Two sentences, purpose front-loaded, routing guidance second. No filler; every clause carries information an agent needs.

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 an output schema handling return values and annotations covering the read-only/open-world profile, the description needs only to establish purpose, input requirement, and sibling routing, all of which it does. Nothing required to call it correctly 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 baseline is 3, but the schema's own param description is the generic 'Resource identifier.' The description meaningfully refines this by stating the id must be a 'known place_id', clarifying the identifier's domain beyond the schema 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 ('Fetch detailed Google Maps information') and scopes it to 'a known place_id'. It explicitly differentiates itself from google_map_search, google_map_place_photos, and google_map_place_reviews, so an agent can route correctly without opening other schemas.

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?

Provides explicit when-to-use ('for a known place_id') plus named alternatives for the other cases: google_map_search to find places, and the photos/reviews tools for that data. The routing condition is fully stated, not implied.

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