ui_invoke

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

The description discloses key behavioral traits beyond annotations: it uses InvokePattern, avoids mouse movement, falls back to Click() if needed, and has a special note about WPF menu headers. It also warns about a common gotcha (breakpoint pause). While it doesn't mention side effects or error behavior, the description adds valuable insight into how the tool operates, which is not contradicted by the sparse annotations.

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 mix of general guidance and very specific troubleshooting (the WPF MenuItem paragraph). While accurate, the WPF section is somewhat tangential and could be shortened or moved to a note, as it is likely a rare edge case. The breakpoint note is useful but interrupts the flow. Overall, it delivers valuable information but could be more streamlined.

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 tool with five optional parameters and no output schema, the description covers critical usage constraints such as the InvokePattern vs Click fallback, breakpoint interaction, and nested menu handling. However, it omits details like how multiple selectors (e.g., name + automation_id) are combined (AND vs OR), behavior when no elements match, or timeout defaults. It addresses common pitfalls but leaves the agent guessing on some execution semantics.

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?

With 0% schema description coverage, the description carries the full burden for parameter semantics. It lists each parameter with a concise purpose: 'root_id: Optional AutomationId to scope search to a subtree' and 'xpath: Optional XPath expression (FlaUI backend only)' adds implementation-specific context. This goes beyond a bare list, though it could benefit from examples or selector precedence logic.

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 function: 'Invoke a UI element using UIA InvokePattern (no mouse movement).' It distinguishes itself from the sibling 'ui_click' by explicitly noting it is 'Preferred over ui_click for buttons, menu items, and hyperlinks' and explains the advantage (works when off-screen or obscured). This makes the purpose unambiguous and differentiates it from similar tools.

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 explicit when-to-use guidance: 'Preferred over ui_click for buttons, menu items, and hyperlinks because it works reliably even when the element is off-screen or partially obscured.' It also gives a direct alternative (ui_click) and a prerequisite ('If app is STOPPED at breakpoint, resume with continue_execution() first'), offering clear direction on when to use this tool versus others.

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