Sets a Qt widget property to a new value via its snapshot reference and property name, enabling targeted UI state changes in running applications.
Set a Qt property on a widget.
Args: ref: Widget ref from qt_snapshot. property_name: Qt property name. value: New value for the property.
| Name | Required | Description | Default |
|---|---|---|---|
| ref | Yes | ||
| value | Yes | ||
| instance | No | ||
| property_name | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations, the description carries the full behavioral burden, and it says nothing about mutation semantics: no mention of failure behavior for unknown or read-only properties, whether the change is applied synchronously or requires a repaint/event-loop pass, or whether it is reversible. Only the bare action is disclosed.
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 lead sentence is front-loaded and the Args block is terse. The property_name and value entries add little beyond the schema titles, but there is no padding or redundancy of note.
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?
An output schema exists, so return values need not be explained, and the ref-to-qt_snapshot linkage is helpful. But for a no-annotation mutation tool in a multi-instance environment (qt_list_instances, qt_select_instance), the unaddressed 'instance' parameter and absent error semantics leave meaningful gaps.
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 adds real meaning for ref ('Widget ref from qt_snapshot') but merely restates property_name and value as their own titles, and never mentions the optional 'instance' parameter that appears in the schema — leaving one of four parameters entirely undocumented anywhere.
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 states a specific verb and resource ('Set a Qt property on a widget'), which is clearly distinct from read-oriented siblings like qt_get_text or qt_widget_details. It does not explicitly differentiate itself from other mutation siblings such as qt_invoke_slot or qt_trigger_action, so it stops 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?
One useful prerequisite is given: the ref comes from qt_snapshot, which tells the agent how to obtain the target. However, there is no guidance on when to use this versus qt_invoke_slot, qt_type, or qt_batch, and no note on whether the widget must be visible or the property writable.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.