Calibrations on disk¶

Audience: config authors trying to find the calibration documentation from the Configuration nav.

Scope: this page is a pointer. The actual content lives in two pages under Calibration:

Calibration sets is the single source of truth for the channel-calibration TOML schema, every transform kind (identity, linear_two_point, polynomial, lookup, piecewise, custom_callable), the UncertaintySpec discipline, and the Setup-tab apply-set diff dialog.
Tune artifacts covers the orthogonal heat-flux artifact subsystem — configs/calibrations/flux/<id>.toml and latest.toml.

The two subsystems share a directory tree and nothing else. Calibration overview explains why.

Where calibrations fit in the configuration story¶

The four configuration "kinds" in capa are:

Kind	File	Topic
Hardware profile	`*.toml`	What devices exist, what channels they expose. See Hardware TOML.
Method	`*.method.toml`	The scripted step sequence. See Method TOML.
Experiment	`*.yaml`	Stitches the others together for one run. See Experiment YAML.
Calibrations	`configs/calibrations/*.toml`	This page.

An experiment YAML references a calibration set by path:

experiment:
  calibration_set: configs/calibrations/thermocouples_2026Q2.toml

At run-arm the set's curves overwrite (non-destructively, in memory) whatever the channels in the hardware profile originally declared. The current bundle writer records the selected set reference in calibration.json (name and revision). Full resolved-curve snapshots are planned, but are not wired into the storage path yet.

A tune artifact is not referenced from the experiment YAML directly — operators cite it (free-form) inside the CAPA profile's HeaterProgram.flux_calibration_ref field, and the tune-procedure itself reads configs/calibrations/flux/latest.toml to pick its initial-setpoint prior.

For everything else, read Calibration sets.