ui_type_text

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

With no annotations provided, the description carries the full behavioral burden. It discloses refusal conditions and reporting of the target element, which is helpful. However, it does not mention side effects like whether existing text is overwritten, whether input events fire, or whether it works with non-input elements like contenteditable. The disclosure is adequate but not exhaustive.

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?

Two concise sentences with no waste. The primary action is front-loaded, and the behavioral caveats follow logically. Every word contributes to understanding.

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?

The description covers the core behavior, failure modes, and even reports the target element, which satisfies the lack of an output schema. It does not specify the return format or whether it triggers events, but for a simple typing action, the information is complete enough. Missing edge cases like handling of special characters are not critical.

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 description coverage is 100%, so the parameters are already well documented in the schema. The description adds no additional meaning beyond what the schema provides (e.g., it doesn't elaborate on the 'expect_focus' behavior beyond the schema's own description). Baseline 3 is appropriate given full schema coverage.

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 a clear action (type text) and a precise target (currently focused input/textarea), and distinguishes itself from sibling UI actions like click, hover, and scroll by its unique purpose. The phrase 'Refuses when nothing is focused' adds behavioral specificity without ambiguity.

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 states a prerequisite (focused element) and implies a use case, but does not explicitly guide when to use this tool versus alternatives like ui_click to focus or ui_keyboard for keyboard input. It lacks 'when not to use' guidance or references to sibling tools.

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