browser_press_key

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

With no annotations, the description carries full behavioral disclosure burden, but it merely states the action without revealing any side effects, such as keydown/keyup behavior, target element requirements, or impact on page state. This is a significant gap for a tool that simulates user input.

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, compact sentence with no superfluous words. It is appropriately sized for the simplicity of the action, and every word contributes to conveying the primary function.

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?

Despite the schema covering parameters, the description lacks crucial context for an agent: it does not mention the optional tabId behavior (even though the schema does), nor any return value or side effects. For a tool with no annotations and no output schema, this level of under-specification leaves the agent with an incomplete picture.

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 input schema provides descriptions for both parameters, covering 100% of them. The description adds no extra parameter meaning, so the baseline score of 3 is appropriate since the schema already handles parameter semantics effectively.

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 verb 'Press' and the resource 'a key on the keyboard', making the core action obvious. It does not explicitly distinguish from sibling tools like browser_type, but the specific mention of keyboard key press separates it adequately from clicking or typing text.

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 on when to use this tool versus alternatives such as browser_type or browser_click. The description does not mention scenarios, prerequisites (e.g., focused element), or exclusion cases, leaving the agent without decision support.

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