MCP-Midscene

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states the action ('presses') but doesn't clarify if this simulates a physical key press, triggers browser events, requires focus on an element, or has side effects like page navigation. For a tool with potential UI interactions, this is a significant gap in 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, clear sentence with zero wasted words. It's front-loaded with the core action, making it easy to parse quickly. Every word earns its place by directly conveying the tool's purpose.

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?

Given the complexity of a keyboard interaction tool with no annotations and no output schema, the description is insufficient. It doesn't explain return values, error conditions, or behavioral nuances like whether key presses are simulated in a browser context. For a tool that could affect UI state, more context is needed to ensure safe and effective use.

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 description coverage is 100%, so the schema already documents all three parameters thoroughly. The description adds no additional meaning beyond what's in the schema, such as examples of key combinations or clarification on how 'locate' and 'deepThink' interact. Baseline 3 is appropriate when the schema does the heavy lifting.

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 action ('presses') and resource ('a specific key on the keyboard'), making the purpose immediately understandable. However, it doesn't explicitly differentiate from sibling tools like 'midscene_aiTap' or 'midscene_aiInput', which might have overlapping keyboard-related functionality.

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. With siblings like 'midscene_aiInput' (likely for text input) and 'midscene_aiTap' (likely for clicking), there's no indication of whether this tool is for navigation keys, modifier keys, or general key presses, leaving usage context ambiguous.

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