FE-778: Offer Sweep toggles on ad-hoc scenarios in the experiment drawer

[kube]

Important

Experimental
Behind the Ad-hoc scenarios and Parameter sweeps feature flags.

Summary

Before this PR, the create-experiment drawer offered a Sweep toggle on the classic scenario parameter rows only. With ad-hoc scenarios enabled the drawer shows every scenario through the ad-hoc form, and the form had no such toggle: neither an inline definition nor a saved scenario shown through it could be swept.

The form gains a sweep selection. Every numeric value carries a Sweep toggle that opens Min and Max bounds, a saved scenario's numeric parameters carry the same toggle in the run-mode rows, and each selection becomes a swept parameter of the experiment. Generated parameters show under the value's path in the sweep navigator and the surface.

9624.mp4

Links

• Ticket FE-778
• Docs Ad-hoc scenarios › Sweep selections
• Docs Experiments › Parameter sweeps

Changes

Ad-hoc form

• sweep joins the form's selections

  Numeric values, Variables and Parameters carry a Sweep toggle; booleans and text carry none.
  The bounds slab shows Min and Max only, no Step and no Scale.

• Run-mode scenario parameter rows carry the toggle

  A saved scenario shown through the form sweeps its numeric parameters like the classic rows do.

• Gutter menu names the row kind after the consumer

  "Swept count" in the experiment drawer, "Optimized count" in the optimization drawer.

Experiments

• Ad-hoc selections become sweep axes

  compileExperimentScenario synthesizes the definition with its selections, and buildAdHocSweepAxes turns each generated parameter's domain into an axis.
  adHocSweeps on the input says whether selections count; off, the definition runs at its fixed values.

• Axes carry a label

  Navigator, surface and summary show Queue › count for adhoc_count_Queue.

• Run-mode form reports ranges and fixed values through one path

  scenarioRunInputs turns a swept Variable into a range from its resolved bounds and every other one into a fixed value.

Review fixes

• A type change drops a Sweep the new type cannot carry

  A swept Variable turned boolean kept its selection with no toggle left to clear it, and the run refused with "boolean values cannot be swept".
  The type change and the toggle-off apply as one action batch, so undo restores both together.

• A selection already on a Variable keeps its toggle whatever the type

  A boolean carrying a Sweep shows the toggle so the definition can be brought back to something that runs.

• Run mode shows no Sweep toggles on the computed net parameters

  The Computed state preview is derived by the host; a toggle there reverted on the next render.

• Run-mode form takes the experiment's inputs, ranges included

  A reseed rebuilds a swept parameter's Sweep from its range instead of dropping it.
  The Computed state previews a swept parameter at the start of its range, the first combination the sweep runs, and its notice names the value.

Test coverage

• parameter-grid.test.ts:

  Ad-hoc axes from integer and continuous domains, error naming the value's label, boolean refusal.

• provider.test.tsx:

  An ad-hoc count selection compiles to a labelled axis and a swept compiler; the flag off runs the fixed value.

• experiment-scenario-inputs.test.ts:

  Fixed values, a range from resolved bounds, no range for a bound that does not resolve.

• ad-hoc-scenario-form.test.tsx, create-experiment-drawer.test.tsx:

  Sweep toggles on numeric values only, in authoring and run mode, and only with both settings on.

• ad-hoc-scenario-form.test.tsx, review fixes:

  A type change to boolean turns the Sweep off as one undo step, a Sweep on a boolean stays clearable, run mode offers no Sweep on net parameters.

• experiment-scenario-run.test.tsx, review fixes:

  A range input seeds the Variable's Sweep and previews the range start with a notice.

How to test

• Open Petrinaut preview on Vercel
• Menu > Load example > SIR Epidemic Model
• Viewport controls > Settings > General > Ad-hoc scenarios
• Viewport controls > Settings > Simulation > Parameter sweeps
• Simulate > Experiments > Create experiment
• Scenario > No scenario, open a place's count cell

  Expect a Sweep toggle under the editor

• Turn Sweep on, set Min 10 and Max 200

  Expect the summary line to name the swept value

• Add a metric, press Run

  Expect a Parameters strip with a slider labelled by the place's path

• Scenario > Seasonal Flu

  Expect a Sweep toggle on each numeric scenario parameter row

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[cursor]

PR Summary

Medium Risk
Touches experiment compilation, sweep axis building, and ad-hoc form state; incorrect bounds or synthesis could block runs or mis-label sweep axes, but behavior is gated behind two experimental flags and covered by new tests.

Overview
Adds parameter sweeps to ad-hoc scenarios in the create-experiment flow when Ad-hoc scenarios and Parameter sweeps are both enabled.

The ad-hoc form gains a sweep selection: numeric slots get a Sweep toggle with Min/Max only (no Step/Scale), mirroring optimize placement. Saved scenarios in run mode get the same toggle on numeric scenario parameters; gutter copy uses Swept count in experiments.

Experiment creation passes adHocSweeps and compileExperimentScenario synthesizes sweep selections via synthesizeAdHocOptimization, builds axes with buildAdHocSweepAxes, and runs sweep sessions from those axes. Swept ad-hoc parameters show human paths (Queue › count) in the navigator, surface, and summary via optional axis label / axisDisplayName.

ExperimentScenarioRun now syncs full parameter inputs (fixed + range), reseeds sweep state from ranges, and previews computed state at each swept parameter’s range minimum. Form history supports batched dispatches so changing a variable type clears an invalid sweep in one undo step.

Docs describe sweep selections on ad-hoc forms and experiment configuration.

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[Copilot]

🟡 Changes recommended

Three moderate issues affect sweep controls, invalid retained selections, and computed-state preview accuracy.

Once you've addressed the issues Copilot identified, you can request another Copilot review.

Pull request overview

Adds parameter sweep support for ad-hoc and saved scenarios in Petrinaut’s experiment drawer, behind the relevant feature flags.

Changes:

• Adds numeric Sweep controls and range handling.
• Compiles ad-hoc selections into labeled sweep axes.
• Updates experiment UI, tests, documentation, and release metadata.

Unresolved findings:

• Moderate: Computed-state parameters incorrectly expose nonfunctional Sweep toggles.
• Moderate: Changing a swept variable to a nonnumeric type can leave an uncleared selection that prevents execution.
• Moderate: Computed-state previews use defaults rather than values represented by active sweep ranges.

File summaries

File	Description
libs/@hashintel/petrinaut/src/ui/views/Editor/panels/SimulateView/shared/surface-frame.tsx	Supports labeled axis options.
libs/@hashintel/petrinaut/src/ui/views/Editor/panels/SimulateView/experiments/sweep-surface.tsx	Uses friendly labels in sweep readouts.
libs/@hashintel/petrinaut/src/ui/views/Editor/panels/SimulateView/experiments/sweep-navigator.tsx	Displays friendly axis labels.
libs/@hashintel/petrinaut/src/ui/views/Editor/panels/SimulateView/experiments/experiment-scenario-run.tsx	Enables saved-scenario sweep inputs.
libs/@hashintel/petrinaut/src/ui/views/Editor/panels/SimulateView/experiments/experiment-scenario-run.test.tsx	Updates run-component tests.
libs/@hashintel/petrinaut/src/ui/views/Editor/panels/SimulateView/experiments/experiment-scenario-inputs.ts	Converts run-form values into fixed or ranged inputs.
libs/@hashintel/petrinaut/src/ui/views/Editor/panels/SimulateView/experiments/experiment-scenario-inputs.test.ts	Tests fixed and ranged input conversion.
libs/@hashintel/petrinaut/src/ui/views/Editor/panels/SimulateView/experiments/create-experiment-drawer.tsx	Integrates sweep controls and summaries.
libs/@hashintel/petrinaut/src/ui/views/Editor/panels/SimulateView/experiments/create-experiment-drawer.test.tsx	Tests feature-flagged drawer controls.
libs/@hashintel/petrinaut/src/ui/components/ad-hoc-scenario-form/variable-rows.tsx	Adds numeric variable Sweep toggles.
libs/@hashintel/petrinaut/src/ui/components/ad-hoc-scenario-form/value-editor.tsx	Displays Min and Max sweep bounds.
libs/@hashintel/petrinaut/src/ui/components/ad-hoc-scenario-form/token-table.tsx	Adds consumer-specific row actions.
libs/@hashintel/petrinaut/src/ui/components/ad-hoc-scenario-form/scenario-parameter-rows.tsx	Adds saved-scenario Sweep toggles.
libs/@hashintel/petrinaut/src/ui/components/ad-hoc-scenario-form/parameter-rows.tsx	Adds parameter Sweep toggles.
libs/@hashintel/petrinaut/src/ui/components/ad-hoc-scenario-form/form-context.ts	Defines sweep selection behavior.
libs/@hashintel/petrinaut/src/ui/components/ad-hoc-scenario-form/ad-hoc-scenario-form.tsx	Supports the sweep form consumer mode.
libs/@hashintel/petrinaut/src/ui/components/ad-hoc-scenario-form/ad-hoc-scenario-form.test.tsx	Tests numeric-only sweep controls.
libs/@hashintel/petrinaut/src/react/experiments/provider/create-experiment.ts	Compiles ad-hoc sweep scenarios.
libs/@hashintel/petrinaut/src/react/experiments/provider.tsx	Starts sessions with compiled sweep axes.
libs/@hashintel/petrinaut/src/react/experiments/provider.test.tsx	Tests ad-hoc sweep compilation.
libs/@hashintel/petrinaut/src/react/experiments/parameter-grid.ts	Builds labeled ad-hoc sweep axes.
libs/@hashintel/petrinaut/src/react/experiments/parameter-grid.test.ts	Tests axis generation and validation.
libs/@hashintel/petrinaut/src/react/experiments/context.ts	Extends experiment creation input.
libs/@hashintel/petrinaut/docs/experiments.md	Documents experiment sweep behavior.
libs/@hashintel/petrinaut/docs/ad-hoc-scenarios.md	Documents ad-hoc sweep selections.
.changeset/adhoc-experiment-sweeps.md	Records the Petrinaut release change.

Review details

• Files reviewed: 26/26 changed files
• Comments generated: 3
• Review effort level: Balanced

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