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 a real behavioral limit — the 20-photo cap and the pointer to apple_maps_place_photos for the full gallery — plus notes it returns only review snippets, not full reviews. Useful beyond the annotations.

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 tight sentences: purpose and returned fields first, then routing to alternatives. No filler, everything 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?

With an output schema present and annotations covering the safety profile, the description supplies everything else an agent needs: purpose, lookup alternatives, and the photo-cap limitation.

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%, and the schema itself documents the two place_id forms, the BCP 47 lang tag, and the ISO country code in detail. The description adds no parameter meaning beyond what the schema already provides, so the baseline 3 applies.

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 (Fetch) and resource (Apple Maps place details) plus the keying mechanism (by place ID), and enumerates the returned fields. It is clearly distinguishable from sibling tools like apple_maps_search and apple_maps_places.

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 routes the agent: use apple_maps_search or apple_maps_autocomplete to find a place, and names apple_maps_places (browse multiple) and apple_maps_place_photos (full gallery) as alternatives with the conditions that select them.

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