browser_key_up

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

No annotations are provided, so the description carries the full burden. It only states the basic action—releasing a key—without disclosing side effects, prerequisites (e.g., whether the key must have been previously pressed), or behavior in edge cases. This falls short of adequate transparency.

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 10-word sentence that directly states the action. It is front-loaded and contains no filler.

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?

The tool is simple, but the description is minimal. It lacks context about session/page behavior (though schema covers this), and does not address error cases or whether the key must be held first. Given no annotations and no output schema, the description could provide more complete guidance.

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 schema already describes pageId and sessionId, but the required 'key' parameter lacks a description. The tool description adds that the key is one 'held by browser_key_down', providing some context, but it doesn't specify accepted key values or formats. With 67% schema coverage, the description partially compensates but leaves the most important parameter underspecified.

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 uses a specific verb ('release') and resource ('keyboard key'), and explicitly references the complementary tool (browser_key_down), clearly distinguishing it from siblings like browser_press_key. It clearly states the tool's function.

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 implies the tool is to be used after browser_key_down, but does not explicitly state when to use it vs alternatives (e.g., browser_press_key for a single key event). No exclusionary guidance is provided.

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