browser_execute_js

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

Annotations already indicate readOnlyHint=false and openWorldHint=true, but the description adds no additional behavioral context such as side effects, security implications, or that scripts can modify the page. The bar is lower with annotations, yet description still adds no value beyond stating the basic function.

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 extremely concise (one sentence) and front-loaded with the core action. It is not verbose and the single sentence earns its place by stating the primary function. However, a bit more structure could improve clarity.

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 a single parameter, full schema coverage, and an output schema (though not shown), the description is adequate for a simple JS execution tool. It covers the essential purpose but lacks nuance like async behavior or error handling, which are minor gaps.

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 coverage is 100% with a clear description for the 'script' parameter ('JavaScript to run in the page context'). The tool description does not add any further meaning beyond what the schema already provides, so baseline score of 3 is appropriate.

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 clearly states the action ('Execute JavaScript') and the resource ('JavaScript in the page context'), and specifies the return type ('as a string'). It effectively distinguishes from sibling tools like devtools_console which may have different execution contexts.

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?

No information is provided about when to use this tool versus alternatives. There is no indication of prerequisites, restrictions, or comparisons to similar browser/debugging tools that execute JavaScript, leaving the agent to infer usage context.

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