type_text

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

The description adds value beyond annotations by disclosing that shell metacharacters are rejected for safety. This is a meaningful behavioral constraint not captured by readOnlyHint=false or openWorldHint=false. It also sets expectations about input restrictions.

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 extremely concise, with two sentences that each serve a clear purpose: first stating the core action, second adding a critical safety detail. No unnecessary words or repetition.

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 typing tool, the description covers the essential behavior and safety mechanism. It does not describe return values or error handling, but given the lack of an output schema and the tool's simplicity, this is not a significant gap. The device_serial parameter is properly explained in the schema.

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 50% (text parameter lacks description). The tool description compensates by clarifying that text is 'restricted plain text' and that metacharacters are rejected, adding meaning to the text parameter. The device_serial parameter is fully described in the schema, so no further explanation is needed.

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 ('Type restricted plain text') and the target ('focused field'), making it distinct from sibling tools like press_key or tap. The qualifier 'restricted plain text' helps differentiate it from other input methods.

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?

Usage is implied rather than explicitly stated. The description does not mention when to use this tool over alternatives, nor does it provide exclusions. However, the context of 'focused field' and the sibling list make the intended use reasonably clear.

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