real_key

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

Annotations (readOnlyHint: false, destructiveHint: false) are neutral. The description adds behavioral context: 'via REAL OS keyboard events', the need to focus the field first, and the platform restriction (Windows only). This goes beyond what annotations provide.

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 three sentences: purpose with examples, usage hint, and constraints. Each sentence adds value with no redundancy. Front-loaded with the core action.

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 one parameter and no output schema, the description covers purpose, usage context, prerequisites (focus), platform restriction, and examples. No gaps remain.

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 only parameter 'key' is documented with examples in both the schema description and the tool description. Schema coverage is 100%, so baseline 3 is appropriate. The description adds no additional semantic details beyond 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?

The description specifies the verb 'Press' and the resource 'key or combo' with examples like 'Enter', 'Tab', 'ctrl+a'. It distinguishes from siblings like 'press_key' by emphasizing 'REAL OS keyboard events', making the purpose clear and specific.

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 tells when to use this tool ('Use "Enter" to submit React composers that ignore synthetic clicks') and includes constraints ('Focus the field first. Windows only.'). It does not explicitly name alternatives but implies them by contrasting with synthetic events.

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