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The Fault-Tolerance (FT) Engine lowers a logical quantum circuit onto a 3-D surface-code lattice and estimates the logical error rate you would observe when running it on error-corrected hardware. You use it to explore how a circuit behaves under a physical noise model and how much its logical error improves as you increase the code distance. Here’s a routed program rendered by the engine — drag to orbit, scroll to zoom, and toggle between the surface-code and logical views:
This viewer is fully interactive — go ahead and play with it! Drag to orbit, scroll to zoom, right-drag to pan, and switch between the surface-code and logical views.
The workflow runs in four stages, each covered on its own page:

Initialize the logical noise model

Turn a physical noise description into logical error-rate information.

Route a program

Lower a transpiled Clifford+T circuit onto the surface-code lattice.

Visualize the routed program

Render the routed program as an interactive 3-D visualization.

Estimate the total error

Combine routing and noise to estimate total error across code distances.
The stages are sequential: the routed program and the logical noise feed the final error estimate. For the full API, see the Error Correction SDK reference.