wait_until_screen_changes

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

The description discloses the core waiting behavior and detection criterion (UI hierarchy differs from the call-time state), which is useful. However, with no annotations provided, it is silent on timeout behavior, polling, and failure semantics, leaving a meaningful gap for an agent deciding how to handle a non-change.

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 two short, purposeful sentences. The first states the exact wait condition, and the second gives a concrete usage scenario. There is no redundancy or 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?

For a simple wait tool with an output schema, the description covers the core behavior and the main use case. But it omits what happens when the timeout is reached and does not clarify the serial parameter, so an orchestrator still has to guess failure semantics.

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 0%, and the description does not mention serial or timeout_seconds at all. It adds no parameter-level meaning beyond what the parameter names and defaults already suggest, so the agent must infer the semantics of serial from context.

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 clear verb-resource pair: wait until the screen's UI content observably changes. It also differentiates from text-based waits by specifying the condition is 'not the same UI hierarchy as at call time' and that it is for cases where you don't know the exact text in advance.

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 tells the agent when to use the tool: after tapping a button when the expected outcome is unknown text but 'something should happen'. It gives clear usage context, though it does not name alternative tools or explicitly state when not to use it.

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