browser_run_code_unsafe

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

Annotations already declare destructiveHint=true and readOnlyHint=false. The description adds crucial context: 'unsafe', 'executes arbitrary JavaScript in the Playwright server process', and 'RCE-equivalent', which goes beyond what annotations convey about the nature of execution and risk.

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?

Two sentences, zero waste, and the key safety warning is front-loaded. Very concise and effectively structured.

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's complexity and lack of output schema, the description sufficiently covers the core behavior and risks. It does not describe the return value, but for an unsafe arbitrary-code tool, that is a minor omission.

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%, with both code and filename fully documented. The description text does not add anything beyond the schema, so a baseline 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 tool runs a Playwright code snippet and executes arbitrary JavaScript in the server process, with an explicit 'unsafe' warning. It distinguishes itself from typical browser actions by highlighting RCE-equivalence, though it does not explicitly differentiate from sibling browser_evaluate.

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 guidance on when to use this tool versus the many sibling tools. It does not mention alternatives or scenarios where this is appropriate or inappropriate, leaving the agent to infer.

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