input_text

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

With no annotations provided, the description carries full responsibility for behavioral disclosure. It reveals key constraints: ASCII-only limitation (adb limitation), the need for focus, and the behavior of submit (Enter key) and clear (deletes existing contents). It does not mention error handling or what happens if focus is missing, but the disclosed constraints are important and non-obvious, making this a solid disclosure.

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 concise and well-structured. The opening sentence immediately states the action and prerequisite, followed by a compact argument list. Every sentence earns its place, and the information is front-loaded. No fluff or redundancy.

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 text-input tool, the description covers everything needed: usage precondition, parameter semantics, and behavioral limitations. An output schema exists (though not shown) to handle return values, so no further description is needed. The description is complete and self-sufficient.

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 0%, so the description must compensate, and it does excellently. Each parameter is explained: text (with ASCII limitation), submit (press Enter), clear (delete existing contents), serial (device serial when multiple attached). This adds substantial meaning beyond the raw schema types and defaults, making the tool safe and easy to invoke correctly.

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 into the focused field.' It specifies the action (typing) and the resource (focused field), and differentiates it from siblings like tap or press_key by focusing on text input. The mention of 'Tap the field first' also implies the necessary precondition, making the purpose unambiguous.

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 clear usage guidance: it instructs the agent to tap the field first to ensure focus, and explains the effect of the submit and clear flags. It does not explicitly list alternatives or when-not scenarios, but the prerequisite is explicit and the tool's role is clear given the sibling set. This is sufficient for an agent to know when to use it.

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