browser_press_key

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

With no annotations, the description carries the burden and does add real context: keyboard targets the currently focused element, valid key string syntax ('Control+a', single characters), and the important fact that main and support browsers 'share nothing' (no shared session state). It omits failure behavior or what happens if nothing is focused.

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 tight sentences, no filler, with the scoping/state-isolation caveat front-loaded alongside the default. Every clause 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?

Output schema exists so return values need not be described. For a two-param tool the description covers key syntax and browser scoping adequately; only the focus prerequisite and error behavior are unstated.

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 0%, so the description must compensate – and it does for both params: it enumerates accepted key value syntax and explains the browser parameter's default ('main unless you say support'). The 'share nothing' note adds semantics not present in 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 (press) and resource (a key) plus the exact target semantics ('whatever has focus'), and enumerates concrete key formats. An agent can distinguish it from browser_type (bulk text entry) and browser_click without opening schemas.

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?

Implies usage via 'whatever has focus' and clarifies the browser default, but never states when to prefer this over browser_type or browser_click, nor that focus must first be established. Usage is inferable rather than explicit.

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