Touchpoint

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

Discloses critical behavioral details including special character handling (\n, \t, \b) and the simulation nature of input. Missing error behavior (what happens if element not focused) and side effects (whether input events fire). With no annotations provided, description carries full burden but leaves operational gaps.

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?

Well-structured with clear sections for purpose, prerequisites, and special characters. Information is front-loaded with the primary action. 'Args:' section is somewhat redundant given the schema, but overall efficient with no extraneous information.

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?

Adequate for parameter description given single input, but lacks error handling documentation important for UI automation tools. Output schema exists so return values need not be described; however, absence of annotations means description should carry more operational context regarding failure modes.

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 has 0% description coverage, but description compensates with detailed special character semantics that apply to the text parameter. 'Args: text: The text to type' provides minimal baseline, but the special characters section adds crucial input semantics not inferable from 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?

States specific verb ('Type') and resource ('text into the currently focused element') and distinguishes mechanism by noting it 'Simulates keyboard input.' References siblings click() and focus() as prerequisites, though could explicitly contrast with set_value or press_key alternatives.

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?

Provides explicit prerequisite instruction: 'Focus a text field first with click() or focus(), then type into it,' establishing clear workflow order. Lacks explicit 'when not to use' guidance or named alternatives (e.g., when to prefer set_value instead).

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