vnc_wait_for_change

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

The description carries the full burden since no annotations are provided, but it only states 'wait until a region changes'. It fails to disclose key behaviors such as timeout behavior (e.g., error on timeout versus returning a status), whether it blocks synchronously, how changes are detected, or what the return value is. This leaves significant ambiguity for the agent.

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 (one sentence, five words) with no wasted words, making it structurally efficient. However, it is overly terse and sacrifices necessary clarity, such as explaining the region parameters or timeout semantics, so it does not earn a high score.

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 5 parameters, no annotations, no output schema, and zero schema parameter descriptions, the description is drastically under-specified. It omits critical context like how the region is defined, timeout behavior, return values, and any prerequisites (e.g., an active connection). This is far from a complete description.

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%, so the description must compensate for parameter meanings. It does not explain that x, y, width, and height define the region rectangle, nor does it describe the timeout parameter's role. The description adds no meaning beyond what the parameter names imply, which is insufficient for such a parameterized tool.

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 'Wait until a region changes' clearly uses a specific verb ('Wait') and resource ('region') with a change condition, making the tool's purpose unambiguous. It distinguishes itself from sibling tools like vnc_screenshot or vnc_get_pixel_color, as none of them describe a blocking wait-for-change operation.

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 the usage: wait for a screen region to change. However, it does not explicitly state when to use this tool versus alternatives (e.g., polling with vnc_screenshot), nor does it mention any exclusions or prerequisites. The need to wait for a change is implied but not verbally contrasted with other methods.

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