Apple MCP Tools

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

With no annotations provided, the description carries full burden for behavioral disclosure but offers minimal information. It mentions three operations (search, create, open) but omits 'list' and 'listById' from the description, creating inconsistency. It doesn't address permissions, rate limits, platform-specific behaviors, or what 'open' actually does (opens the app? displays details?).

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 a single, efficient sentence that front-loads the core functionality. However, it's incomplete - it mentions only three of the five available operations ('search, create, and open' while omitting 'list' and 'listById'), which creates a minor structural issue despite the concise phrasing.

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?

For a tool with 8 parameters, 5 distinct operations, no annotations, and no output schema, the description is inadequate. It doesn't explain the relationship between operations, doesn't mention the 'operation' parameter that drives functionality, and provides no guidance on return values or error conditions. The agent would struggle to use this effectively without heavy schema reliance.

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?

The input schema has 100% description coverage, providing detailed documentation for all 8 parameters including required conditions and formats. The description adds no parameter-specific information beyond what's already in the schema, so it meets the baseline of 3 where 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?

The description clearly states the tool's purpose as 'Search, create, and open reminders in Apple Reminders app' - a specific verb+resource combination that identifies the target application and core operations. However, it doesn't distinguish this from sibling tools like 'calendar' or 'notes' which might have similar CRUD patterns, missing explicit differentiation.

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 no guidance on when to use this tool versus alternatives. There's no mention of when to choose 'reminders' over sibling tools like 'calendar' for time-based tasks, or when to use specific operations like 'search' versus 'list'. The agent must infer usage entirely from the operation parameter.

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