browser_evaluate

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

With no annotations, the description carries the full behavioral burden. It notes that a result is returned, but for an arbitrary-code-execution tool it omits critical traits: that the script can mutate page state, what happens on error/timeout, how results are serialized, and any security or sandbox constraints.

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?

A single front-loaded sentence with zero waste; the action and scope come first and nothing is padded.

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?

Adequate for a two-parameter tool with full schema coverage and a documented script parameter, but no output schema and no annotations means the risky, error-prone aspects of arbitrary JS execution go undisclosed.

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%, so baseline is 3. The description adds minimal meaning by clarifying that tabId targets the active tab by default and a specified tab otherwise, but offers no syntax or format detail beyond the schema.

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?

States a specific verb (executes), resource (arbitrary JavaScript), and scope (context of the active or specified tab), plus the return behavior. This clearly distinguishes it from sibling interaction tools like browser_get_dom, browser_click, and browser_type.

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 never says when to use this tool versus alternatives such as browser_get_dom for DOM extraction or browser_click for interaction. No prerequisites, exclusions, or routing guidance are provided.

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