apple_maps_guides_lookup

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

With no annotations provided, the description carries the burden. It discloses the batch limit (up to 20), the not_found behavior for missing ids, and the exclusion of publisher details. It also lists the return fields. This is transparent for a read-only lookup, though it doesn't mention potential errors or rate limits, which are minor for this type of tool.

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?

The description is three sentences, each carrying essential information: function and output, use case, and exclusions with an alternative. It's front-loaded with the main action and efficiently structured without redundancy.

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?

There is no output schema, so the description must explain return values. It does so comprehensively by listing all fields, describing not_found behavior, and clarifying what's not included. The use case (e.g., guide_ids a place carries) is also given. For a batch lookup tool, this is complete.

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% - all three parameters have descriptions. The description adds marginal value by giving an example of guide_ids usage and clarifying the limit, but the schema already defines the format. Since the schema does the heavy lifting, a baseline score of 3 is appropriate.

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 clearly states the tool's function: resolving Apple Guide ids to guide summaries. It lists the exact fields returned and explicitly differentiates from the single-guide endpoint by noting publisher details are excluded. This distinguishes it from sibling tools like apple_maps_guide and apple_maps_guides_publisher.

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 description provides clear usage context: it's for batch lookup of guide summaries given ids (e.g., from a place). It also points to an alternative (the guide endpoint) for publisher details and places. However, it doesn't explicitly state when to use this over other guide lookup tools like apple_maps_guides_cities or apple_maps_guides_nearby, but it gives enough context for the primary use case.

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