comet_evaluate

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

No annotations are provided, so the description must fully carry behavioral disclosure. It only restates the evaluation action and does not mention possible page mutation, navigation side effects, error behavior, or whether the expression result is returned. Arbitrary JavaScript execution can have significant side effects, so this gap matters.

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 compact and front-loads the core purpose in the first sentence. The Args block partially repeats the purpose, but it is short, conventional, and directly documents the parameter.

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?

The tool has only one parameter and an output schema, so return-value documentation is not strictly needed. However, the description omits behavioral caveats and usage prerequisites for an operation that can execute arbitrary code in the page, leaving an agent with enough to call the tool but not enough to understand its full impact.

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 define the sole parameter. It adds that 'expression' is a JavaScript expression to evaluate in page context, which is minimal but sufficient for a single string parameter. It provides no examples, syntax expectations, or async/return-value details.

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 uses a specific verb ('Evaluate') and identifies the resource clearly: 'a JavaScript expression in the current Comet page.' It is immediately clear what the tool does and is distinct from sibling tools like click, type, and read_page, though it does not explicitly name or contrast them.

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?

There is no guidance about when to use this tool versus alternatives, when not to use it, or prerequisites such as an active page connection. The phrase 'current Comet page' implies a prior navigation step but does not state what must be true before evaluation.

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