ui_action

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

With no annotations provided, the description carries the full burden of behavioral disclosure, but it offers nothing. It does not mention side effects, waiting/retry behavior, error handling, state changes, or return values, leaving the invocation behavior completely opaque.

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 a single sentence, but it suffers from under-specification rather than being efficiently concise. The words provide minimal information and do not justify their presence; more content is needed to be minimally useful.

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?

This tool has five parameters, an enum of actions, and no output schema, yet the description does not cover the range of actions, value handling, session context, or expected results. It is severely incomplete for a tool of this complexity.

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 0%. The description only mentions 'selector' generically and does not explain the 'action' enum, the optional 'value' parameter, 'timeoutMs', 'sessionId', or how they interact. It adds no meaning beyond the raw schema fields.

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 'Perform a direct UI action on a selector' essentially restates the tool name (ui_action) with generic wording. It does not enumerate the specific actions (click, fill, type, press, etc.) available in the schema, nor does it distinguish the tool from sibling UI operations like ui_navigate or ui_extract.

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?

There is no guidance on when to use this tool versus alternatives such as ui_navigate, ui_extract, or ui_run_flow. The description provides no context about suitable scenarios, restrictions, or selection criteria.

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