Inspect the interface as it runs.

MCP: inspect, edit and test

An agent can read the running DOM, computed styles and box model, edit CSS, type and click, then inspect feedback and capture the window. This real stdio MCP session sets the inspector to 250px, changes the gap to 20px, renames the workspace and checks the save result.

• MCP configuration, arguments and test steps →

DOM, styles and box model

Locate elements in the DOM tree, read effective computed styles and inspect dimensions and positions in the box model. Edit styles live and check the element preview and app window.

Lua: debug inside event callbacks

After a save click, a Lua breakpoint pauses before the counter update. Locals and upvalues show the current state. Inspect the call stack, step through code, set conditional breakpoints, evaluate expressions and pause on exceptions.

Performance: find repeated work in recorded frames

Record UI actions and inspect style, layout, painting and submission per frame. Use node attribution for hot nodes and invalidation reasons, with CPU and memory samples for context. This is one local demo recording, not a general benchmark. Unavailable backend metrics remain explicitly unavailable.

• Recording modes and metrics →
• Debugging security →