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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered. The description adds a useful behavioral detail, namely that results combine location-curated guides with the enclosing guides city, but says nothing about result limits, pagination, or ordering.

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?

A single, front-loaded sentence that leads with what is retrieved before the parenthetical detail. It is efficient, though the parenthetical and 'plus the guides city' clause slightly dilute the core statement.

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?

An output schema exists, so return values need not be explained, and annotations carry the safety profile. Still, for a 5-parameter spatial tool the description omits how span, country, and lang shape results, leaving a modest completeness gap.

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 latitude/longitude/span/country/lang are already documented in the schema. The description only alludes to the coordinate, adding no syntax or effect details beyond the schema, which is the expected baseline for full coverage.

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?

The description states a specific resource (Apple Guides curated) and scope (area around a coordinate, plus the parent guides city), so the agent knows exactly what it returns. It does not, however, name or contrast with the many sibling guide tools (apple_maps_guides, apple_maps_guides_lookup, apple_maps_guides_cities), so differentiation is left to inference.

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?

There is no explicit when-to-use or when-not-to-use guidance and no naming of alternatives like apple_maps_guides_lookup or apple_maps_guide. The coordinate-centric framing implies a spatial use case but the agent gets no routing help among the sibling guide tools.

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