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

Annotations already declare readOnlyHint and openWorldHint, so safety is covered. The description adds genuinely new context: the tool operates on indoor venue directories (mall/airport/stadium) and may either enumerate the full directory or drill into one category. It does not discuss pagination behavior, but the output schema and the limit parameter schema carry that.

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 with no filler. The capability statement comes first and the sibling-routing sentence follows, so the most selection-relevant information is front-loaded.

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?

Output schema exists, so return values need no explanation; annotations declare the read-only open-world profile; parameters are fully described. The description supplies the disambiguation and scope an agent needs to pick this tool correctly.

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 description coverage is 100%, so place_id, category, lang, country, and limit are all documented with defaults and examples in the schema itself. The description adds only the notion of an optional category filter, which is already schema-level. Baseline 3 applies when the schema does the heavy lifting.

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?

Specific verb (browse) plus a precisely scoped resource: the indoor directory for a mall, airport, or stadium place ID, with an optional category filter. It also names the sibling tools it is not, so the agent can discriminate it from apple_maps_place and apple_maps_search without opening any 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 second sentence explicitly routes: use apple_maps_place for a single venue's details and apple_maps_search to find a place, leaving this tool for browsing an indoor directory. The conditional use of the category parameter (omit to list the directory, supply to browse one category) is stated in the schema and echoed in the tool's scope.

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