Agent skill · microsoft
experiments
Use when adding, changing, or reviewing a VS Code A/B experiment, either an experiment-controlled setting or a treatment read with the assignment service, and when deciding whether and where to log an `experimentTrigger` event for a triggered ExP scorecard.
What it needs
About 3k tokens when loaded.
What this skill does
Experiments Controlling behavior Experiment-controlled setting: add experiment: { mode: 'auto' } to the setting's schema, or mode: 'startup' to only pick up changed assignments on startup. ExP then sets the setting's default through the treatment config.<setting id> (or experiment.name), and code reads the setting with IConfigurationService as usual. Values that users set themselves still win. Use this when users could reasonably choose the behavior themselves. Treatment: read a value with IWorkbenchAssignmentService.getTreatment<T>(name). It resolves to undefined without an assignment, so keep a fallback, and read it again on onDidRefetchAssignments. Use this for values that are not user preferences, such as copy or variant names. To try an assignment locally, set experiments.override.<treatment name> in your user settings, for example "experiments.override.config.chat.mySetting.enabled": true. Trigger events for triggered scorecards A triggered scorecard only compares users who reached the moment where control and treatment behave differently, so users that the experiment never affected don't dilute the result. Log that moment with the helpers in experimentTrigger.ts: They log the shared experimentTrigger event with the treatment name as treatmentName, at most once per window or process, so they can run on every evaluation. Base the scorecard's trigger on that event (monacoworkbench/experimentTrigger) and its treatmentName. Don't add feature-specific trigger events. When to use one Use a trigger when only some assigned users are affected, at an identifiable moment: an action, a surface that only appears in some situations, or a code path that only some sessions reach. …
How to use it
Reference it in AdaL, Claude Code, Cursor or any coding agent — nothing to install:
@skills microsoft/experiments