app_state

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

No annotations are provided, so the description must fully disclose behavior. It does well by detailing what data is reported and the optional stale JS check. However, it doesn't mention whether the tool mutates any state (likely read-only, but unstated), or any authentication requirements or side effects.

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 concise at three sentences, front-loads the core purpose, and every sentence provides distinct value. No filler.

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?

Given the tool has 3 parameters, no output schema, and no annotations, the description is quite complete—covers purpose, optional usage, and a concrete use case. It could hint at return format, but not strictly necessary for selection/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 the baseline is 3. The description adds value by explaining how source_path is used to compare mtime with Metro markers, which goes beyond the schema. No additional nuance is needed for the other parameters.

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 reports an app's runtime state, enumerates specific pieces of information (installed, running, foreground, top activity, etc.), and distinguishes it from other tools by mentioning Metro/Expo capabilities and stale JavaScript detection.

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 gives explicit usage guidance: 'Run this FIRST when JS edits seem to have no effect.' It also explains the optional source_path usage for comparison. However, it does not explicitly exclude cases where a simpler tool might suffice, though the context of debugging JS edits is clear.

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