iOS Simulator MCP

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

The description adds valuable behavioral context beyond annotations by revealing the implementation method ('using killall'), which suggests a forceful termination that might abruptly end the recording. Annotations indicate this is not read-only and operates in an open world, but the description provides specific execution details that help anticipate behavior.

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 immediately conveys the core functionality. Every word earns its place: 'Stops' (action), 'simulator video recording' (target), 'using killall' (implementation detail). No wasted words or 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?

For a zero-parameter tool with annotations covering read/write status and world assumptions, the description provides sufficient context about what the tool does and how it operates. The main gap is lack of output information (no output schema), but the description compensates somewhat by hinting at the termination behavior.

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?

With 0 parameters and 100% schema description coverage, the baseline would be 4. The description appropriately doesn't discuss parameters since none exist, maintaining focus on the tool's action without unnecessary elaboration.

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 specific action ('Stops') and target resource ('simulator video recording'), using the exact verb 'stop' that matches the tool name. It distinguishes from sibling tools like 'record_video' by indicating the opposite action, providing clear 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 implies usage context by specifying 'simulator video recording', suggesting it should be used when a recording is active. However, it doesn't explicitly state when NOT to use it or mention alternatives like 'screenshot' for capturing simulator state without recording.

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