ui_click

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

With no annotations, the description carries the behavioral disclosure burden. It goes beyond a simple 'click' by revealing the return payload (Portal, hints, focused overlay), locator priority order, coordinate fallback behavior, and the rejection of stale VTable coordinates when `analysis_id` is provided. This is strong, though it does not cover all side effects or preconditions.

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 compact but information-dense. The first sentence gives the purpose and immediate result; the second lays out the locator order and fallback rule. Every sentence contributes, and the most important information is front-loaded.

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 16-parameter tool with no annotations and 0% schema coverage, the description covers the central behavior well but leaves several operational parameters undocumented. The presence of an output schema lowers the need to describe return values, yet the gaps around `frame`, `observe_after`, and `expect_input` mean the definition is not fully complete.

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%, so the description must compensate. It does add real semantic value by explaining how CSS, role/name, XPath, text/placeholder, and x/y relate to each other, and by qualifying `analysis_id` behavior. But several parameters remain unexplained: `frame`, `settle_ms`, `timeout_ms`, `max_results`, `expect_input`, and `observe_after`, so compensation is only partial.

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 opens with a specific verb and resource: 'unified click page controls' and states what it returns (Portal, hints, focused overlay). It is clear about the core operation, but it does not explicitly differentiate this tool from the sibling `ui_interact`, so it falls short of a 5.

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 meaningful usage context: it says multiple candidate locators can be passed from analysis results, defines a fixed execution order, and marks coordinates as a fallback. However, it never says when to prefer `ui_click` over alternatives like `ui_interact` or `vtable_cell_click`, leaving the when-to-use guidance mostly implied.

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