browser_evaluate

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

Annotations already carry destructiveHint=true and readOnlyHint=false, so the risk profile is partially disclosed. The description adds the behavioral nuance that evaluation can target a page or an element, but it does not explain side effects, execution context, or what happens to the page state. With annotations covering the main safety signals, this is adequate but not rich.

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 a single concise, front-loaded sentence with no wasted words. It is minimally sufficient as a title-like summary, though it could be slightly expanded to improve other dimensions without becoming verbose.

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 tool that executes arbitrary JavaScript and is marked as destructive, this description is thin. It does not explain return behavior, the role of the filename parameter, or how this differs from browser_run_code_unsafe. The schema fills in parameter details, but the overall operational context remains incomplete for an agent deciding whether and how to invoke it.

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 all four parameters are already documented structurally. The description adds no additional meaning beyond recognizing page or element targeting, which matches the existing schema descriptions. The baseline of 3 applies because the schema carries the parameter documentation burden.

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 ('Evaluate') and resource ('JavaScript expression on page or element'), making the core operation clear. It does not explicitly differentiate itself from the closely related sibling browser_run_code_unsafe, which also executes JavaScript, but it does convey that evaluation can be scoped to a page or a particular element.

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 like browser_run_code_unsafe, nor any mention of when it is appropriate to evaluate on the page versus on an element. The description implies JavaScript execution but provides no context, exclusions, or selection criteria.

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