playwright_evaluate

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states what the tool does but lacks critical details: it doesn't specify execution context (e.g., current page, frame), error handling, security implications, or what happens if the script fails. This is a significant gap for a tool that executes arbitrary code.

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—a single, direct sentence with no wasted words. It's front-loaded with the core action, making it easy to understand at a glance while remaining complete in its basic statement.

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 complexity of executing JavaScript in a browser (which can have side effects, errors, and security considerations), the description is inadequate. With no annotations, no output schema, and minimal behavioral details, it fails to provide enough context for safe and effective use, especially compared to sibling tools that are more straightforward (e.g., playwright_click).

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?

The schema description coverage is 100%, with the single parameter 'script' clearly documented as 'JavaScript code to execute'. The description adds no additional meaning beyond this, such as examples of valid scripts or constraints. However, since the schema fully covers the parameter, the 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 context ('in the browser console'), which is specific and unambiguous. However, it doesn't explicitly differentiate from sibling tools like playwright_get or playwright_navigate, which might also involve browser interaction but serve different purposes.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention scenarios where executing JavaScript is preferred over other playwright tools (e.g., for dynamic content manipulation vs. simple navigation), nor does it specify prerequisites or exclusions.

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