fix: allow experimental flags to override umbrella (#29273)

packages/core/src/flag/flag.ts

@@ -8,6 +8,10 @@ function truthy(key: string) {
 const OPENCODE_EXPERIMENTAL = truthy("OPENCODE_EXPERIMENTAL")
 const copy = process.env["OPENCODE_EXPERIMENTAL_DISABLE_COPY_ON_SELECT"]
 
+function enabledByExperimental(key: string) {
+  return process.env[key] === undefined ? OPENCODE_EXPERIMENTAL : truthy(key)
+}
+
 export const Flag = {
   OTEL_EXPORTER_OTLP_ENDPOINT: process.env["OTEL_EXPORTER_OTLP_ENDPOINT"],
   OTEL_EXPORTER_OTLP_HEADERS: process.env["OTEL_EXPORTER_OTLP_HEADERS"],
@@ -42,7 +46,7 @@ export const Flag = {
   OPENCODE_DB: process.env["OPENCODE_DB"],
 
   OPENCODE_WORKSPACE_ID: process.env["OPENCODE_WORKSPACE_ID"],
-  OPENCODE_EXPERIMENTAL_WORKSPACES: OPENCODE_EXPERIMENTAL || truthy("OPENCODE_EXPERIMENTAL_WORKSPACES"),
+  OPENCODE_EXPERIMENTAL_WORKSPACES: enabledByExperimental("OPENCODE_EXPERIMENTAL_WORKSPACES"),
 
   // Evaluated at access time (not module load) because tests, the CLI, and
   // external tooling set these env vars at runtime.

packages/opencode/src/effect/runtime-flags.ts

@@ -1,4 +1,4 @@
-import { Config, ConfigProvider, Context, Effect, Layer } from "effect"
+import { Config, ConfigProvider, Context, Effect, Layer, Option } from "effect"
 import { ConfigService } from "@/effect/config-service"
 
 const bool = (name: string) => Config.boolean(name).pipe(Config.withDefault(false))
@@ -9,7 +9,9 @@ const positiveInteger = (name: string) =>
   )
 const experimental = bool("OPENCODE_EXPERIMENTAL")
 const enabledByExperimental = (name: string) =>
-  Config.all({ experimental, enabled: bool(name) }).pipe(Config.map((flags) => flags.experimental || flags.enabled))
+  Config.all({ experimental, enabled: Config.boolean(name).pipe(Config.option) }).pipe(
+    Config.map((flags) => Option.getOrElse(flags.enabled, () => flags.experimental)),
+  )
 
 export class Service extends ConfigService.Service<Service>()("@opencode/RuntimeFlags", {
   autoShare: bool("OPENCODE_AUTO_SHARE"),

packages/opencode/test/effect/runtime-flags.test.ts

@@ -213,6 +213,21 @@ describe("RuntimeFlags", () => {
     }),
   )
 
+  it.effect("specific experimental flags override OPENCODE_EXPERIMENTAL", () =>
+    Effect.gen(function* () {
+      const flags = yield* readFlags.pipe(
+        Effect.provide(
+          fromConfig({
+            OPENCODE_EXPERIMENTAL: "true",
+            OPENCODE_EXPERIMENTAL_ICON_DISCOVERY: "false",
+          }),
+        ),
+      )
+
+      expect(flags.experimentalIconDiscovery).toBe(false)
+    }),
+  )
+
   it.effect("experimentalOxfmt defaults to false", () =>
     Effect.gen(function* () {
       const flags = yield* readFlags.pipe(Effect.provide(fromConfig({})))