get_app_state

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

Annotations already declare readOnlyHint=true and idempotentHint=true, indicating non-destructive, safe operation. The description adds value by specifying the exact state values (not installed, not running, background, foreground). It does not contradict annotations. No discussion of error handling or permissions, but the behavioral core is well covered.

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, well-structured sentence. It front-loads the primary action and result, then lists the possible return values. Every word adds value, and there is no redundancy or fluff.

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 simple read-only tool with one parameter and no output schema, the description is nearly complete. It explains what the tool does and what it returns. However, it does not explicitly mention the requirement of a mobile context or session, though 'Mobile-only' hints at it. The annotations cover safety. Overall, adequate but with a minor 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?

The schema has 100% description coverage for the single parameter bundleId, including an example. The description does not add any additional semantic meaning beyond what the schema already provides. Baseline score of 3 is appropriate since the parameter is fully documented in the schema.

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 that the tool returns the current state of a mobile app, listing specific possible states (not installed, not running, background, foreground). It also explicitly says 'Mobile-only', which distinguishes it from tools that work on desktop. This is a specific verb+resource with clear scope.

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 includes 'Mobile-only', which provides a clear usage context (not for desktop). However, it does not explicitly mention when not to use this tool or name alternative tools like 'list_apps' for comparison. The purpose is clear, but exclusion guidance is absent.

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