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 the Worldwide default scope and the directory nature of the result, which is useful context, but nothing about rate limits or result completeness. With annotations carrying the main burden, a 3 is appropriate.

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, zero waste, with the core purpose front-loaded before the downstream-usage detail. Every clause earns its place.

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 described. The description covers purpose, default scope, and how the output feeds other tools, leaving only minor gaps about result ordering or pagination that are not critical for invocation.

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 both lang and country are already documented with format and defaults. The description's 'by region' and 'country context' phrasing loosely aligns with these but adds no syntax or format detail beyond the schema, 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 (List) and resource (city directory for Apple Guides), and specifies what the output contains (city IDs and country context). This clearly distinguishes it from siblings like apple_maps_guides_nearby or apple_maps_guides_lookup, which serve different retrieval intents.

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?

It gives a concrete downstream workflow: pass a returned city ID to apple_maps_guides or apple_maps_guides_publishers, and omit for Worldwide scope. It does not, however, say when to prefer this over sibling lookups like apple_maps_guides_lookup or apple_maps_guides_nearby, so it is clear context without explicit exclusions.

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