Type Android text

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

Annotations provide no safety or behavior hints (all false). The description adds value by disclosing that the tool 'Reports the Unicode limitation instead of hiding it,' which tells the agent that there is a known limitation regarding Unicode input and that the tool will surface it. This goes beyond what the schema conveys, though it does not detail the exact limitation.

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 very brief at two clauses total. It front-loads the core purpose. The second clause is somewhat vague ('Reports the Unicode limitation instead of hiding it') but adds relevant detail. It could be slightly clearer, but overall earns its place without extra words.

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 tool has three required parameters and an output schema (not shown), the description lacks sufficient completeness. It does not mention return values, side effects (e.g., does it clear existing text?), or how the Unicode limitation affects usage. An agent would need to infer or discover additional behavior from other sources.

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 67% (two of three parameters have schema descriptions). The description does not add any parameter-specific information; it neither explains the 'text' field nor provides usage context not already in the schema. With high coverage, a baseline of 3 is appropriate, but the description fails to compensate for the undocumented 'text' 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?

The description clearly states the tool's purpose: 'Type text through ADB's virtual keyboard.' This specifies the action (type) and the resource (text via ADB virtual keyboard). It also mentions reporting a Unicode limitation, which adds further clarity and distinguishes it from sibling input tools like tap, swipe, or key combination.

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. It does not mention that for non-text input one should use mobile_input_tap or mobile_input_swipe, nor does it specify prerequisites or scenarios where this tool is appropriate. The sibling tools include many input variants, but no comparative context is given.

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