browser_press_key

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

The description does not disclose behavioral traits such as whether the key press is sent to the focused element, whether it triggers keydown and keyup events, or special behaviors for modifier keys. No annotations are provided to compensate.

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 at 4 words, with no unnecessary information. It is front-loaded and every word earns its place.

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?

For a simple tool with a well-documented schema and no output schema, the description is minimally adequate. It lacks context about behavior when no element is focused or whether the press is simulated, but the schema covers the parameters sufficiently.

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 the description adds minimal value. It lists example keys ('Enter', 'Escape') which are also in the schema description. The meaning of the parameters is clear from the schema, justifying a baseline of 3.

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 'Press a keyboard key' clearly states the verb (press) and resource (keyboard key), distinguishing it from sibling tools like browser_click or browser_type. However, it could be more specific about what constitutes a key press (e.g., simulating keydown and keyup).

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 like browser_type or browser_click. For example, it does not indicate that press_key is for single key commands while type is for text input.

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