nex_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 behavioral burden. It discloses only the pairing with key_down; it says nothing about what happens if the key is not held, whether key events are dispatched, or error behavior for an input-mutation tool.

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?

A single front-loaded sentence with zero filler. Every word contributes to identifying the action and its counterpart.

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 three-parameter browser input tool with no annotations and no output schema, the description is too thin. It omits key value format, default page/session behavior, and return/error semantics that an agent needs to invoke it correctly.

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 only 67%, and the description adds no meaning for the 'key' parameter (e.g., accepted key names like 'Shift' or 'a') nor for pageId/sessionId defaults. It does not compensate for the undocumented required parameter.

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 and resource: 'Release a keyboard key.' It also names the inverse sibling (nex_browser_key_down), so an agent can distinguish this from press_key without opening either schema.

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 reference to nex_browser_key_down implies this should be called after a key-down, but there is no explicit when-to-use guidance, no exclusions, and no comparison to siblings like nex_browser_press_key.

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