Activate app

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

Annotations declare readOnlyHint=false, idempotentHint=true, and destructiveHint=false. The description adds the concrete side effect that the user's current window loses focus, and clarifies that it gives keyboard focus. It doesn't contradict annotations and provides useful behavioral context beyond the structured flags.

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?

Two sentences, zero filler. The primary purpose is in the first sentence, and the second sentence packs usage guidance and side effect efficiently. All content earns its place.

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 single-parameter, side-effectful operation with no output schema, the description covers the action, the trigger conditions, the side effect, and the parameter format (via schema). Nothing an agent needs to invoke it correctly is missing.

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 parameter 'app' is fully documented with format ('App name, bundle id, or pid exactly as reported by list_apps'). The description adds no additional parameter-specific details, which is acceptable given the high coverage.

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 states a specific verb ('bring') and resource ('an app's windows'), and clearly defines the outcome: foreground and keyboard focus. It also distinguishes from siblings by noting that element-id actions like click and set_value do not need it, which helps an agent pick the right tool.

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?

It explicitly says when to call it: before press_key or type_text when the target app is not frontmost, and explicitly says when not needed. It also mentions the side effect of losing focus in the previous window, giving clear situational guidance.

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