diff --git a/packages/core/src/filesystem/location-watcher.ts b/packages/core/src/filesystem/location-watcher.ts
index 40a76c4de30..2ba0b90a8d6 100644
--- a/packages/core/src/filesystem/location-watcher.ts
+++ b/packages/core/src/filesystem/location-watcher.ts
@@ -93,7 +93,7 @@ const layer = Layer.effect(
     )
     yield* policy.observe(reconcile)
     yield* Effect.gen(function* () {
-      yield* plugins.flush
+      yield* plugins.awaitActivation
       yield* reconcile(policy.current())
     }).pipe(
       Effect.catchCauseIf(
diff --git a/packages/core/src/plugin/supervisor-service.ts b/packages/core/src/plugin/supervisor-service.ts
index 8cb09b5f02b..73eaf186ef0 100644
--- a/packages/core/src/plugin/supervisor-service.ts
+++ b/packages/core/src/plugin/supervisor-service.ts
@@ -8,10 +8,12 @@ import { Context, Effect } from "effect"
  */
 export interface Interface {
   /**
-   * Wait for the plugin generation to settle. Use this rarely: blocking reads,
-   * UI startup, or other unrelated work on plugin boot should be avoided.
+   * Wait for configured plugin activation to settle, including missing-package installs.
+   * Completion does not imply every plugin succeeded.
+   * Interrupting this wait does not cancel activation. Use rarely: avoid blocking reads,
+   * UI startup, or unrelated work on plugin boot.
    */
-  readonly flush: Effect.Effect<void>
+  readonly awaitActivation: Effect.Effect<void>
 }
 
 export class Service extends Context.Service<Service, Interface>()("@opencode/PluginSupervisor") {}
diff --git a/packages/core/src/plugin/supervisor.ts b/packages/core/src/plugin/supervisor.ts
index 7ec540c80aa..961127a154c 100644
--- a/packages/core/src/plugin/supervisor.ts
+++ b/packages/core/src/plugin/supervisor.ts
@@ -169,7 +169,7 @@ export const layer = Layer.effect(
         Stream.map(() => undefined),
       ),
     ).pipe(
-      // Make accepted work visible to flush before coalescing the burst.
+      // Make accepted work visible to awaitActivation before coalescing the burst.
       Stream.mapEffect(() =>
         Effect.gen(function* () {
           observed++
@@ -191,7 +191,7 @@ export const layer = Layer.effect(
       Effect.forkScoped({ startImmediately: true }),
     )
     yield* Effect.sleep("24 hours").pipe(Effect.andThen(activate()), Effect.forever, Effect.forkScoped)
-    return Service.of({ flush: ready.await })
+    return Service.of({ awaitActivation: ready.await })
   }),
 )
 
diff --git a/packages/core/src/session.ts b/packages/core/src/session.ts
index 25298d3f415..626dfc29d4d 100644
--- a/packages/core/src/session.ts
+++ b/packages/core/src/session.ts
@@ -407,7 +407,7 @@ const layer = Layer.effect(
         const session = yield* result.get(input.sessionID)
         const commands = yield* Effect.gen(function* () {
           const plugins = yield* PluginSupervisor.Service
-          yield* plugins.flush
+          yield* plugins.awaitActivation
           return yield* Command.Service
         }).pipe(instances.provide(session))
         const delivery = input.delivery ?? "steer"
diff --git a/packages/core/src/session/context.ts b/packages/core/src/session/context.ts
index 18e535f83da..4ec2b323ed0 100644
--- a/packages/core/src/session/context.ts
+++ b/packages/core/src/session/context.ts
@@ -125,7 +125,7 @@ const layer = Layer.effect(
       if (session.location.directory !== location.directory || session.location.workspaceID !== location.workspaceID)
         return yield* Effect.interrupt
 
-      yield* plugins.flush
+      yield* plugins.awaitActivation
       yield* mcpTools.flush
       const agent = yield* agents.select(session.agent)
       if (!agent.info) return yield* new AgentNotFoundError({ sessionID: session.id, agent: session.agent ?? agent.id })
diff --git a/packages/core/src/session/prompt.ts b/packages/core/src/session/prompt.ts
index 71a8f0db700..9cd8df4d4f2 100644
--- a/packages/core/src/session/prompt.ts
+++ b/packages/core/src/session/prompt.ts
@@ -37,7 +37,7 @@ export const make = Effect.fn("SessionPrompt.make")(function* () {
     messageID: SessionMessage.ID
     input: Input
   }) {
-    yield* plugins.flush
+    yield* plugins.awaitActivation
     const event = yield* hooks.trigger("session", "prompt", {
       sessionID: request.sessionID,
       messageID: request.messageID,
diff --git a/packages/core/src/session/revert.ts b/packages/core/src/session/revert.ts
index b9f60d485ba..05cfd634794 100644
--- a/packages/core/src/session/revert.ts
+++ b/packages/core/src/session/revert.ts
@@ -38,7 +38,7 @@ export const make = Effect.fn("SessionRevert.make")(function* () {
   const snapshot = yield* Snapshot.Service
 
   const stage: Interface["stage"] = Effect.fn("SessionRevert.stage")(function* (input) {
-    yield* plugins.flush
+    yield* plugins.awaitActivation
     const original = input.session.revert?.snapshot
       ? Snapshot.ID.make(input.session.revert.snapshot)
       : yield* snapshot.capture()
@@ -66,7 +66,7 @@ export const make = Effect.fn("SessionRevert.make")(function* () {
   })
 
   const clear: Interface["clear"] = Effect.fn("SessionRevert.clear")(function* (session) {
-    yield* plugins.flush
+    yield* plugins.awaitActivation
     if (!session.revert) return
     const original = session.revert.snapshot ? Snapshot.ID.make(session.revert.snapshot) : undefined
     if (original)
diff --git a/packages/core/src/session/runner/llm.ts b/packages/core/src/session/runner/llm.ts
index c9622e5ee45..7bbc89e2171 100644
--- a/packages/core/src/session/runner/llm.ts
+++ b/packages/core/src/session/runner/llm.ts
@@ -57,7 +57,7 @@ const layer = Layer.effect(
         const control = pending.type === "compaction" || pending.type === "move"
         if (promotable === "steer" && pending.delivery === "queue" && !control) return DrainResult.Complete()
       }
-      yield* plugins.flush
+      yield* plugins.awaitActivation
       yield* settleStaleToolCalls(sessionID)
 
       const advanceToStep = Effect.fn("SessionRunner.advanceToStep")(() =>
diff --git a/packages/core/src/session/session.ts b/packages/core/src/session/session.ts
index 7dd1db4df85..df0473acd7d 100644
--- a/packages/core/src/session/session.ts
+++ b/packages/core/src/session/session.ts
@@ -196,7 +196,7 @@ export const make = Effect.fn("Session.make")(function* () {
       // Resolve shell services here without pinning Session events to this Location after a move.
       const shell = yield* Effect.gen(function* () {
         const plugins = yield* PluginSupervisor.Service
-        yield* plugins.flush
+        yield* plugins.awaitActivation
         return yield* Shell.Service
       }).pipe(instances.provide(session))
       const started = yield* shell
diff --git a/packages/core/test/config/plugin.test.ts b/packages/core/test/config/plugin.test.ts
index 53f45a14638..ca20987ccb2 100644
--- a/packages/core/test/config/plugin.test.ts
+++ b/packages/core/test/config/plugin.test.ts
@@ -490,7 +490,7 @@ describe("PluginSupervisor config", () => {
     ),
   )
 
-  it.live("unblocks flush when plugin activation fails", () =>
+  it.live("unblocks awaitActivation when plugin activation fails", () =>
     Effect.gen(function* () {
       const sdk = yield* SdkPlugins.Service
       yield* sdk.register(define({ id: "duplicate-id", effect: () => Effect.void }))
@@ -530,9 +530,9 @@ describe("PluginSupervisor config", () => {
         const plugins = yield* Plugin.Service
         expect((yield* plugins.list()).map((plugin) => String(plugin.id))).toContain("opencode.provider.openai")
         const supervisor = yield* PluginSupervisor.Service
-        expect(Option.isNone(yield* supervisor.flush.pipe(Effect.timeoutOption("20 millis")))).toBeTrue()
+        expect(Option.isNone(yield* supervisor.awaitActivation.pipe(Effect.timeoutOption("20 millis")))).toBeTrue()
         yield* Effect.promise(() => Bun.write(path.join(global.tmp, "cold-plugin", "release"), ""))
-        yield* supervisor.flush.pipe(Effect.timeout("2 seconds"))
+        yield* supervisor.awaitActivation.pipe(Effect.timeout("2 seconds"))
         expect((yield* plugins.list()).map((plugin) => String(plugin.id))).toContain("cold-plugin")
       }),
     ),
@@ -542,7 +542,7 @@ describe("PluginSupervisor config", () => {
 
 const ready = Effect.fnUntraced(function* () {
   const supervisor = yield* PluginSupervisor.Service
-  yield* supervisor.flush
+  yield* supervisor.awaitActivation
 })
 
 const waitForFile = (file: string) =>
diff --git a/packages/core/test/filesystem/watcher.test.ts b/packages/core/test/filesystem/watcher.test.ts
index 9ad0401684a..e97ac7bb533 100644
--- a/packages/core/test/filesystem/watcher.test.ts
+++ b/packages/core/test/filesystem/watcher.test.ts
@@ -31,7 +31,7 @@ const it = testEffect(AppNodeBuilder.build(LayerNode.group([FSUtil.node, Bus.nod
 const configLayer = Config.testLayer()
 const pluginNode = makeLocationNode({
   service: PluginSupervisor.Service,
-  layer: Layer.succeed(PluginSupervisor.Service, PluginSupervisor.Service.of({ flush: Effect.void })),
+  layer: Layer.succeed(PluginSupervisor.Service, PluginSupervisor.Service.of({ awaitActivation: Effect.void })),
   deps: [],
 })
 
@@ -313,7 +313,7 @@ describe("LocationWatcher subscriptions", () => {
         Effect.gen(function* () {
           const policy = yield* LocationWatcherPolicy.Service
           yield* policy.transform((draft) => draft.add([".git"]))
-          return PluginSupervisor.Service.of({ flush: Effect.void })
+          return PluginSupervisor.Service.of({ awaitActivation: Effect.void })
         }),
       ),
       deps: [LocationWatcherPolicy.node],
diff --git a/packages/core/test/fixture/prompt-location.ts b/packages/core/test/fixture/prompt-location.ts
index 9f4a66fe5c1..71a3c4706ac 100644
--- a/packages/core/test/fixture/prompt-location.ts
+++ b/packages/core/test/fixture/prompt-location.ts
@@ -31,7 +31,7 @@ export const promptLocationNode = makeGlobalNode({
                 }),
                 Layer.succeed(FSUtil.Service, fs),
                 Layer.succeed(PluginSupervisor.Service, {
-                  flush: Effect.void,
+                  awaitActivation: Effect.void,
                 }),
                 Layer.mock(Reference.Service, { refresh: () => Effect.void }),
               ),
diff --git a/packages/core/test/formatter.test.ts b/packages/core/test/formatter.test.ts
index 2f4adf3b13e..e8ba3e4fd5b 100644
--- a/packages/core/test/formatter.test.ts
+++ b/packages/core/test/formatter.test.ts
@@ -44,7 +44,7 @@ function withFormatter<A, E, R>(
       Effect.andThen(
         Effect.gen(function* () {
           const plugins = yield* PluginSupervisor.Service
-          yield* plugins.flush
+          yield* plugins.awaitActivation
           return yield* body(yield* Formatter.Service, directory)
         }).pipe(
           Effect.scoped,
diff --git a/packages/core/test/instance-plugins.test.ts b/packages/core/test/instance-plugins.test.ts
index 786a033afe7..f0a3606f241 100644
--- a/packages/core/test/instance-plugins.test.ts
+++ b/packages/core/test/instance-plugins.test.ts
@@ -69,7 +69,7 @@ describe("InstancePlugins", () => {
           const agents = (ref: Location.Ref) =>
             Effect.gen(function* () {
               const supervisor = yield* PluginSupervisor.Service
-              yield* supervisor.flush
+              yield* supervisor.awaitActivation
               const service = yield* Agent.Service
               return {
                 bound: yield* service.get(Agent.ID.make("thread-a-agent")),
diff --git a/packages/core/test/instance-vanilla.test.ts b/packages/core/test/instance-vanilla.test.ts
index a18d16934a9..e07a5c9055e 100644
--- a/packages/core/test/instance-vanilla.test.ts
+++ b/packages/core/test/instance-vanilla.test.ts
@@ -77,7 +77,7 @@ describe("Instance vanilla", () => {
           const read = (ref: Location.Ref) =>
             Effect.gen(function* () {
               const supervisor = yield* PluginSupervisor.Service
-              yield* supervisor.flush
+              yield* supervisor.awaitActivation
               const config = yield* Config.Service
               const discovery = yield* InstructionDiscovery.Service
               const tools = yield* Tool.Service
@@ -145,7 +145,7 @@ describe("Instance vanilla", () => {
           const ref = Location.Ref.make({ directory: AbsolutePath.make(directory) })
           yield* Effect.gen(function* () {
             const supervisor = yield* PluginSupervisor.Service
-            yield* supervisor.flush
+            yield* supervisor.awaitActivation
             const config = yield* Config.Service
             // Only the pathless host-injected document; nothing file-backed.
             const entries = yield* config.entries()
diff --git a/packages/core/test/location-layer.test.ts b/packages/core/test/location-layer.test.ts
index 5d7de96afd4..4c166f94fb9 100644
--- a/packages/core/test/location-layer.test.ts
+++ b/packages/core/test/location-layer.test.ts
@@ -199,7 +199,7 @@ describe("LocationServiceMap", () => {
           const ref = Location.Ref.make({ directory: AbsolutePath.make(dir.path) })
           const read = Effect.gen(function* () {
             const supervisor = yield* PluginSupervisor.Service
-            yield* supervisor.flush
+            yield* supervisor.awaitActivation
             const agents = yield* Agent.Service
             return yield* agents.get(id)
           })
@@ -233,14 +233,14 @@ describe("LocationServiceMap", () => {
           const context = yield* locations.contextEffect(Location.Ref.make({ directory: AbsolutePath.make(dir.path) }))
           yield* Deferred.await(started)
 
-          const flushFiber = yield* PluginSupervisor.Service.use((supervisor) => supervisor.flush).pipe(
+          const activationFiber = yield* PluginSupervisor.Service.use((supervisor) => supervisor.awaitActivation).pipe(
             Effect.provide(context),
             Effect.forkChild,
           )
-          expect(flushFiber.pollUnsafe()).toBeUndefined()
+          expect(activationFiber.pollUnsafe()).toBeUndefined()
           yield* Deferred.succeed(release, undefined)
-          yield* Fiber.join(flushFiber)
-          yield* PluginSupervisor.Service.use((supervisor) => supervisor.flush).pipe(
+          yield* Fiber.join(activationFiber)
+          yield* PluginSupervisor.Service.use((supervisor) => supervisor.awaitActivation).pipe(
             Effect.provide(context),
             Effect.timeout("1 second"),
           )
@@ -281,7 +281,7 @@ describe("LocationServiceMap", () => {
           const context = yield* locations.contextEffect(Location.Ref.make({ directory: AbsolutePath.make(dir.path) }))
           yield* Deferred.await(firstStarted)
 
-          const flushFiber = yield* PluginSupervisor.Service.use((supervisor) => supervisor.flush).pipe(
+          const activationFiber = yield* PluginSupervisor.Service.use((supervisor) => supervisor.awaitActivation).pipe(
             Effect.provide(context),
             Effect.forkChild({ startImmediately: true }),
           )
@@ -296,10 +296,10 @@ describe("LocationServiceMap", () => {
 
           yield* Deferred.succeed(releaseFirst, undefined)
           yield* Deferred.await(secondStarted)
-          expect(flushFiber.pollUnsafe()).toBeUndefined()
+          expect(activationFiber.pollUnsafe()).toBeUndefined()
 
           yield* Deferred.succeed(releaseSecond, undefined)
-          yield* Fiber.join(flushFiber)
+          yield* Fiber.join(activationFiber)
         }),
       ),
     ),
@@ -352,22 +352,22 @@ describe("LocationServiceMap", () => {
           )
           yield* Fiber.join(updated)
 
-          const flushFiber = yield* PluginSupervisor.Service.use((supervisor) => supervisor.flush).pipe(
+          const activationFiber = yield* PluginSupervisor.Service.use((supervisor) => supervisor.awaitActivation).pipe(
             Effect.provide(context),
             Effect.forkChild,
           )
           yield* Deferred.succeed(releaseFirst, undefined)
           yield* Deferred.await(secondStarted)
-          expect(flushFiber.pollUnsafe()).toBeUndefined()
+          expect(activationFiber.pollUnsafe()).toBeUndefined()
           yield* Deferred.succeed(releaseSecond, undefined)
-          yield* Fiber.join(flushFiber)
+          yield* Fiber.join(activationFiber)
           expect(activations.count).toBe(2)
         }),
       ),
     ),
   )
 
-  itWithSdk.live("keeps flush pending while startup updates continue", () =>
+  itWithSdk.live("keeps awaitActivation pending while startup updates continue", () =>
     Effect.acquireRelease(
       Effect.promise(() => tmpdir()),
       (dir) => Effect.promise(() => dir[Symbol.asyncDispose]()),
@@ -376,7 +376,7 @@ describe("LocationServiceMap", () => {
         Effect.gen(function* () {
           const locations = yield* LocationServiceMap.Service
           const context = yield* locations.contextEffect(Location.Ref.make({ directory: AbsolutePath.make(dir.path) }))
-          const flushFiber = yield* PluginSupervisor.Service.use((supervisor) => supervisor.flush).pipe(
+          const activationFiber = yield* PluginSupervisor.Service.use((supervisor) => supervisor.awaitActivation).pipe(
             Effect.provide(context),
             Effect.forkChild({ startImmediately: true }),
           )
@@ -387,8 +387,8 @@ describe("LocationServiceMap", () => {
             () => bus.publish(SdkPlugins.Updated, {}).pipe(Effect.andThen(Effect.sleep("50 millis"))),
             { discard: true },
           )
-          expect(flushFiber.pollUnsafe()).toBeUndefined()
-          yield* Fiber.join(flushFiber)
+          expect(activationFiber.pollUnsafe()).toBeUndefined()
+          yield* Fiber.join(activationFiber)
         }),
       ),
     ),
@@ -412,7 +412,7 @@ describe("LocationServiceMap", () => {
 
           const locations = yield* LocationServiceMap.Service
           const context = yield* locations.contextEffect(Location.Ref.make({ directory: AbsolutePath.make(dir.path) }))
-          yield* PluginSupervisor.Service.use((supervisor) => supervisor.flush).pipe(Effect.provide(context))
+          yield* PluginSupervisor.Service.use((supervisor) => supervisor.awaitActivation).pipe(Effect.provide(context))
           expect(activations.count).toBe(1)
 
           yield* Bus.Service.use((bus) => bus.publish(Config.Event.Updated, {})).pipe(Effect.provide(context))
@@ -424,7 +424,7 @@ describe("LocationServiceMap", () => {
     ),
   )
 
-  itWithSdk.live("keeps flush open while later hot reload runs", () =>
+  itWithSdk.live("keeps awaitActivation pending while later hot reload runs", () =>
     Effect.acquireRelease(
       Effect.promise(() => tmpdir()),
       (dir) => Effect.promise(() => dir[Symbol.asyncDispose]()),
@@ -433,7 +433,7 @@ describe("LocationServiceMap", () => {
         Effect.gen(function* () {
           const locations = yield* LocationServiceMap.Service
           const context = yield* locations.contextEffect(Location.Ref.make({ directory: AbsolutePath.make(dir.path) }))
-          yield* PluginSupervisor.Service.use((supervisor) => supervisor.flush).pipe(Effect.provide(context))
+          yield* PluginSupervisor.Service.use((supervisor) => supervisor.awaitActivation).pipe(Effect.provide(context))
 
           const started = yield* Deferred.make<void>()
           const release = yield* Deferred.make<void>()
@@ -451,20 +451,20 @@ describe("LocationServiceMap", () => {
           )
           yield* Deferred.await(started)
 
-          const flushFiber = yield* PluginSupervisor.Service.use((supervisor) => supervisor.flush).pipe(
+          const activationFiber = yield* PluginSupervisor.Service.use((supervisor) => supervisor.awaitActivation).pipe(
             Effect.provide(context),
             Effect.forkChild({ startImmediately: true }),
           )
-          expect(flushFiber.pollUnsafe()).toBeUndefined()
+          expect(activationFiber.pollUnsafe()).toBeUndefined()
           yield* Deferred.succeed(release, undefined)
-          yield* Fiber.join(flushFiber)
+          yield* Fiber.join(activationFiber)
           yield* Deferred.await(completed)
         }),
       ),
     ),
   )
 
-  itWithSdk.live("does not cancel activation when a flush waiter is interrupted", () =>
+  itWithSdk.live("does not cancel activation when an awaitActivation waiter is interrupted", () =>
     Effect.acquireRelease(
       Effect.promise(() => tmpdir()),
       (dir) => Effect.promise(() => dir[Symbol.asyncDispose]()),
@@ -489,15 +489,15 @@ describe("LocationServiceMap", () => {
           const locations = yield* LocationServiceMap.Service
           const context = yield* locations.contextEffect(Location.Ref.make({ directory: AbsolutePath.make(dir.path) }))
           yield* Deferred.await(started)
-          const flushFiber = yield* PluginSupervisor.Service.use((supervisor) => supervisor.flush).pipe(
+          const activationFiber = yield* PluginSupervisor.Service.use((supervisor) => supervisor.awaitActivation).pipe(
             Effect.provide(context),
             Effect.forkChild({ startImmediately: true }),
           )
-          yield* Fiber.interrupt(flushFiber)
+          yield* Fiber.interrupt(activationFiber)
 
           yield* Deferred.succeed(release, undefined)
           yield* Deferred.await(completed)
-          yield* PluginSupervisor.Service.use((supervisor) => supervisor.flush).pipe(
+          yield* PluginSupervisor.Service.use((supervisor) => supervisor.awaitActivation).pipe(
             Effect.provide(context),
             Effect.timeout("500 millis"),
           )
@@ -519,7 +519,7 @@ describe("LocationServiceMap", () => {
           const plugins = yield* Effect.gen(function* () {
             const plugins = yield* Plugin.Service
             const supervisor = yield* PluginSupervisor.Service
-            yield* supervisor.flush
+            yield* supervisor.awaitActivation
             return yield* plugins.list()
           }).pipe(
             Effect.scoped,
@@ -546,7 +546,7 @@ describe("LocationServiceMap", () => {
           yield* Effect.gen(function* () {
             const registry = yield* Plugin.Service
             const supervisor = yield* PluginSupervisor.Service
-            yield* supervisor.flush
+            yield* supervisor.awaitActivation
             expect((yield* registry.list()).map((plugin) => String(plugin.id))).toEqual(["opencode.agent"])
 
             yield* Effect.promise(() => fs.writeFile(file, JSON.stringify({ plugins: ["-*", "opencode.command"] })))
@@ -710,7 +710,7 @@ describe("LocationServiceMap", () => {
               const catalog = yield* Catalog.Service
               yield* catalog.transform((editor) => editor.provider.update(providerID, () => {}))
               const supervisor = yield* PluginSupervisor.Service
-              yield* supervisor.flush
+              yield* supervisor.awaitActivation
               const registry = yield* Tool.Service
               return {
                 providers: yield* catalog.provider.all(),
@@ -992,7 +992,7 @@ describe("LocationServiceMap", () => {
           yield* Effect.gen(function* () {
             const supervisor = yield* PluginSupervisor.Service
             const mcp = yield* Mcp.Service
-            yield* supervisor.flush
+            yield* supervisor.awaitActivation
             expect(observed.example).toBe(false)
             yield* mcp.add("dynamic", {
               type: "remote",
diff --git a/packages/core/test/session-generate.test.ts b/packages/core/test/session-generate.test.ts
index e6fc2889d93..fbde4fae8db 100644
--- a/packages/core/test/session-generate.test.ts
+++ b/packages/core/test/session-generate.test.ts
@@ -111,7 +111,7 @@ const discovery = Layer.mock(InstructionDiscovery.Service, {
 const skills = Layer.mock(SkillInstructions.Service, { load: () => Effect.succeed(Instructions.empty) })
 const references = Layer.mock(ReferenceInstructions.Service, { load: () => Effect.succeed(Instructions.empty) })
 const mcp = Layer.mock(McpInstructions.Service, { load: () => Effect.succeed(Instructions.empty) })
-const plugins = Layer.mock(PluginSupervisor.Service, { flush: Effect.void })
+const plugins = Layer.mock(PluginSupervisor.Service, { awaitActivation: Effect.void })
 const tools = Layer.mock(Tool.Service, {
   snapshot: () =>
     Effect.succeed({
diff --git a/packages/core/test/session-owned.test.ts b/packages/core/test/session-owned.test.ts
index da18ebe03f1..0717aa01562 100644
--- a/packages/core/test/session-owned.test.ts
+++ b/packages/core/test/session-owned.test.ts
@@ -95,7 +95,7 @@ const setup = Effect.fnUntraced(function* (options?: {
   )
   const hooks = yield* PluginHooks.Service.pipe(Effect.provide(LayerNode.compile(PluginHooks.node)))
   const locations: Location.Ref[] = []
-  const flushes: Location.Ref[] = []
+  const activationWaits: Location.Ref[] = []
   const resumes: SessionSchema.ID[] = []
   const wakes: Array<{ sessionID: SessionSchema.ID; pending: SessionMessage.ID[]; enqueued: number }> = []
   const execution = SessionExecution.Service.of({
@@ -143,8 +143,8 @@ const setup = Effect.fnUntraced(function* (options?: {
             }),
           options?.snapshot?.(ref) ?? Layer.mock(Snapshot.Service, {}),
           Layer.succeed(PluginSupervisor.Service, {
-            flush: Effect.sync(() => {
-              flushes.push(ref)
+            awaitActivation: Effect.sync(() => {
+              activationWaits.push(ref)
             }),
           }),
         ),
@@ -175,7 +175,7 @@ const setup = Effect.fnUntraced(function* (options?: {
     }),
     Effect.provideService(SessionExecution.Service, options?.execution ?? execution),
   )
-  return { sessions, hooks, locations, flushes, resumes, wakes, db: database.db, bus, store }
+  return { sessions, hooks, locations, activationWaits, resumes, wakes, db: database.db, bus, store }
 })
 
 describe("Session-owned handles", () => {
@@ -252,7 +252,7 @@ describe("Session-owned handles", () => {
       const calls: string[] = []
       yield* fixture.hooks.register("session", "prompt", (event) =>
         Effect.sync(() => {
-          expect(fixture.flushes).toEqual([source])
+          expect(fixture.activationWaits).toEqual([source])
           calls.push(event.prompt.text)
           event.prompt.text += " prepared"
         }),
@@ -277,7 +277,7 @@ describe("Session-owned handles", () => {
       )
       expect(calls).toEqual(["Original"])
       expect(fixture.locations).toEqual([source])
-      expect(fixture.flushes).toEqual([source])
+      expect(fixture.activationWaits).toEqual([source])
       expect(fixture.wakes).toEqual([
         { sessionID, pending: [synthetic.id, first.id], enqueued: 2 },
         { sessionID, pending: [synthetic.id, first.id], enqueued: 2 },
@@ -363,7 +363,7 @@ describe("Session-owned handles", () => {
       expect(fixture.locations).toEqual([source])
       yield* prompt
       expect(fixture.locations).toEqual([source, destination])
-      expect(fixture.flushes).toEqual([source, destination])
+      expect(fixture.activationWaits).toEqual([source, destination])
       expect((yield* fixture.sessions.forSession(otherID).get()).location).toEqual(source)
     }),
   )
@@ -408,7 +408,7 @@ describe("Session-owned handles", () => {
       expect(
         events.filter((event) => event.type === SessionEvent.Skill.Activated.type).map((event) => event.location),
       ).toEqual([undefined, undefined, source])
-      expect(fixture.flushes).toEqual([])
+      expect(fixture.activationWaits).toEqual([])
       expect(fixture.resumes).toEqual([])
       expect(fixture.wakes).toEqual([])
     }),
@@ -442,7 +442,7 @@ describe("Session-owned handles", () => {
       expect(yield* handle.get()).toEqual(before)
       expect(yield* handle.inbox()).toEqual([])
       expect(yield* fixture.store.context(sessionID)).toEqual([])
-      expect(fixture.flushes).toEqual([])
+      expect(fixture.activationWaits).toEqual([])
       expect(fixture.resumes).toEqual([])
       expect(fixture.wakes).toEqual([])
     }),
@@ -776,7 +776,7 @@ describe("Session-owned handles", () => {
 
       expect(captures).toEqual([source, destination])
       expect(fixture.locations).toEqual([source, destination, destination])
-      expect(fixture.flushes).toEqual([source, destination, destination])
+      expect(fixture.activationWaits).toEqual([source, destination, destination])
       expect((yield* handle.get()).revert).toBeUndefined()
     }),
   )
@@ -800,7 +800,7 @@ describe("SessionPrompt construction", () => {
               Layer.mergeAll(
                 Layer.succeed(PluginHooks.Service, fixture.hooks),
                 Layer.succeed(PluginSupervisor.Service, {
-                  flush: Effect.sync(() => {
+                  awaitActivation: Effect.sync(() => {
                     calls.push("ready")
                   }),
                 }),
@@ -842,8 +842,8 @@ describe("SessionRevert construction", () => {
         Effect.provide(
           Layer.merge(
             Layer.succeed(PluginSupervisor.Service, {
-              flush: Effect.sync(() => {
-                calls.push("flush")
+              awaitActivation: Effect.sync(() => {
+                calls.push("awaitActivation")
               }),
             }),
             Layer.mock(Snapshot.Service, {
@@ -871,7 +871,7 @@ describe("SessionRevert construction", () => {
       yield* revert
         .stage({ session, messageID: boundary.id, files: false })
         .pipe(Effect.satisfiesServicesType<never>(), Effect.provide(unrelated))
-      expect(calls).toEqual(["flush", "capture", "capture", "diff"])
+      expect(calls).toEqual(["awaitActivation", "capture", "capture", "diff"])
 
       const staged = yield* handle.get()
       expect(staged.revert?.snapshot).toBe(Snapshot.ID.make("captured-tree"))
@@ -879,7 +879,15 @@ describe("SessionRevert construction", () => {
       const cleared = yield* handle.get()
       expect(cleared.revert).toBeUndefined()
       yield* revert.clear(cleared).pipe(Effect.satisfiesServicesType<never>(), Effect.provide(unrelated))
-      expect(calls).toEqual(["flush", "capture", "capture", "diff", "flush", "restore", "flush"])
+      expect(calls).toEqual([
+        "awaitActivation",
+        "capture",
+        "capture",
+        "diff",
+        "awaitActivation",
+        "restore",
+        "awaitActivation",
+      ])
     }),
   )
 })
diff --git a/packages/core/test/session-prompt-hooks.test.ts b/packages/core/test/session-prompt-hooks.test.ts
index 27193f2a2cd..59e6950be17 100644
--- a/packages/core/test/session-prompt-hooks.test.ts
+++ b/packages/core/test/session-prompt-hooks.test.ts
@@ -60,7 +60,7 @@ const setup = Effect.gen(function* () {
   const services = locations.get(session.location)
   const hooks = yield* Effect.gen(function* () {
     const plugins = yield* PluginSupervisor.Service
-    yield* plugins.flush
+    yield* plugins.awaitActivation
     return yield* PluginHooks.Service
   }).pipe(Effect.provide(services))
   return { sessions, session, hooks, services }
diff --git a/packages/core/test/session-prompt.test.ts b/packages/core/test/session-prompt.test.ts
index 21aff7005c6..36290e41ebf 100644
--- a/packages/core/test/session-prompt.test.ts
+++ b/packages/core/test/session-prompt.test.ts
@@ -115,7 +115,7 @@ const locations = (references: Layer.Layer<Reference.Service>) =>
                     Layer.succeed(
                       PluginSupervisor.Service,
                       PluginSupervisor.Service.of({
-                        flush: Effect.sync(() => (ready = true)),
+                        awaitActivation: Effect.sync(() => (ready = true)),
                       }),
                     ),
                   ),
diff --git a/packages/core/test/session-revert.test.ts b/packages/core/test/session-revert.test.ts
index 9080771aa9a..e8ba1c5029f 100644
--- a/packages/core/test/session-revert.test.ts
+++ b/packages/core/test/session-revert.test.ts
@@ -67,7 +67,7 @@ describe("Session.revert files", () => {
 
         yield* Effect.gen(function* () {
           const plugins = yield* PluginSupervisor.Service
-          yield* plugins.flush
+          yield* plugins.awaitActivation
           const snapshot = yield* Snapshot.Service
           const before = yield* snapshot.capture()
           if (!before) throw new Error("Initial snapshot missing")
diff --git a/packages/core/test/session-runner-recorded.test.ts b/packages/core/test/session-runner-recorded.test.ts
index dd8e05825c0..2bda7afcc11 100644
--- a/packages/core/test/session-runner-recorded.test.ts
+++ b/packages/core/test/session-runner-recorded.test.ts
@@ -85,7 +85,10 @@ const referenceInstructions = Layer.mock(ReferenceInstructions.Service, {
 })
 const mcpInstructions = Layer.mock(McpInstructions.Service, { load: () => Effect.succeed(Instructions.empty) })
 const config = Config.testLayer()
-const pluginSupervisor = Layer.succeed(PluginSupervisor.Service, PluginSupervisor.Service.of({ flush: Effect.void }))
+const pluginSupervisor = Layer.succeed(
+  PluginSupervisor.Service,
+  PluginSupervisor.Service.of({ awaitActivation: Effect.void }),
+)
 const promptCatalog = Layer.mock(Catalog.Service, {
   provider: {
     get: () => Effect.undefined,
diff --git a/packages/core/test/session-runner.test.ts b/packages/core/test/session-runner.test.ts
index c5a2bf30ad1..8bd2304bc05 100644
--- a/packages/core/test/session-runner.test.ts
+++ b/packages/core/test/session-runner.test.ts
@@ -206,7 +206,7 @@ const makeRunnerState = () => {
     systemUnavailable: false,
     systemLoadHook: Effect.void,
     skillBaselines: new Map<Agent.ID, string>(),
-    pluginFlushHook: Effect.void,
+    pluginActivationHook: Effect.void,
     authorizations: new Array<Tool.Context>(),
     executions: new Array<string>(),
     closedTransports: new Array<Session.ID>(),
@@ -390,7 +390,7 @@ const layer = Layer.unwrap(
     const pluginSupervisor = Layer.succeed(
       PluginSupervisor.Service,
       PluginSupervisor.Service.of({
-        flush: Effect.suspend(() => state.pluginFlushHook),
+        awaitActivation: Effect.suspend(() => state.pluginActivationHook),
       }),
     )
     const promptCatalog = Layer.mock(Catalog.Service, {
@@ -1840,7 +1840,7 @@ describe("SessionRunnerLLM", () => {
 
   scenario("waits for initial plugin readiness before constructing the model request", function* (s) {
     const release = yield* Deferred.make<void>()
-    s.pluginFlushHook = Deferred.await(release)
+    s.pluginActivationHook = Deferred.await(release)
     yield* s.session.prompt({ sessionID, text: "Wait for plugins", resume: false })
 
     s.requests.length = 0
diff --git a/packages/core/test/session-skill.test.ts b/packages/core/test/session-skill.test.ts
index 4ff1c2051ce..4f7b752a3b6 100644
--- a/packages/core/test/session-skill.test.ts
+++ b/packages/core/test/session-skill.test.ts
@@ -53,7 +53,7 @@ const locations = makeGlobalNode({
               list: () => Effect.succeed([info]),
             }),
             Layer.succeed(PluginSupervisor.Service, {
-              flush: Effect.void,
+              awaitActivation: Effect.void,
             }),
             Layer.mock(Reference.Service, { refresh: () => Effect.void }),
           ),
diff --git a/packages/core/test/session-title.test.ts b/packages/core/test/session-title.test.ts
index 8f508d1bb4b..31cc90ea11c 100644
--- a/packages/core/test/session-title.test.ts
+++ b/packages/core/test/session-title.test.ts
@@ -130,7 +130,7 @@ const it = testEffect(
       Catalog.node.replace(catalog),
       SessionRunnerModel.node.replace(models),
       Location.node.replace(Location.boundNode({ directory: AbsolutePath.make("/project") })),
-      PluginSupervisor.node.replace(Layer.mock(PluginSupervisor.Service, { flush: Effect.void })),
+      PluginSupervisor.node.replace(Layer.mock(PluginSupervisor.Service, { awaitActivation: Effect.void })),
     ],
   ),
 )
diff --git a/packages/core/test/tool-shell.test.ts b/packages/core/test/tool-shell.test.ts
index 779b0353a6a..0733a34680e 100644
--- a/packages/core/test/tool-shell.test.ts
+++ b/packages/core/test/tool-shell.test.ts
@@ -129,7 +129,7 @@ const shellPluginSupervisor = makeLocationNode({
   service: PluginSupervisor.Service,
   layer: Layer.effect(
     PluginSupervisor.Service,
-    registerToolPlugin(ShellTool.Plugin).pipe(Effect.as(PluginSupervisor.Service.of({ flush: Effect.void }))),
+    registerToolPlugin(ShellTool.Plugin).pipe(Effect.as(PluginSupervisor.Service.of({ awaitActivation: Effect.void }))),
   ),
   deps: [
     Config.node,
@@ -220,7 +220,7 @@ const withSession = <A, E, R>(directory: string, body: (registry: Tool.Interface
     const locationLayer = locations.get(location)
     return yield* Effect.gen(function* () {
       const plugins = yield* PluginSupervisor.Service
-      yield* plugins.flush
+      yield* plugins.awaitActivation
       const registry = yield* Tool.Service
       return yield* body(registry)
     }).pipe(Effect.provide(locationLayer), Effect.ensuring(locations.invalidate(location)))
diff --git a/packages/core/test/tool-subagent.test.ts b/packages/core/test/tool-subagent.test.ts
index 460b800cede..962473a479f 100644
--- a/packages/core/test/tool-subagent.test.ts
+++ b/packages/core/test/tool-subagent.test.ts
@@ -107,7 +107,9 @@ const subagentPluginSupervisor = makeLocationNode({
   service: PluginSupervisor.Service,
   layer: Layer.effect(
     PluginSupervisor.Service,
-    registerToolPlugin(SubagentTool.Plugin).pipe(Effect.as(PluginSupervisor.Service.of({ flush: Effect.void }))),
+    registerToolPlugin(SubagentTool.Plugin).pipe(
+      Effect.as(PluginSupervisor.Service.of({ awaitActivation: Effect.void })),
+    ),
   ),
   deps: [Agent.node, Config.node, Permission.node, PluginRuntime.node, Tool.node],
 })
@@ -155,7 +157,9 @@ const completionIt = testEffect(
 const withSubagent = (location: Location.Ref) =>
   Effect.gen(function* () {
     const locations = yield* LocationServiceMap.Service
-    yield* PluginSupervisor.Service.use((supervisor) => supervisor.flush).pipe(Effect.provide(locations.get(location)))
+    yield* PluginSupervisor.Service.use((supervisor) => supervisor.awaitActivation).pipe(
+      Effect.provide(locations.get(location)),
+    )
     yield* Agent.Service.use((agents) =>
       agents.transform((draft) => {
         // The caller identity used by executeTool; subagent permission asserts against it.
diff --git a/packages/sdk/test/embedded.test.ts b/packages/sdk/test/embedded.test.ts
index 2a7f7a13d88..e1f687b400d 100644
--- a/packages/sdk/test/embedded.test.ts
+++ b/packages/sdk/test/embedded.test.ts
@@ -48,7 +48,7 @@ for (const selection of ["explicit", "default"] as const) {
             PluginSupervisor.Service,
             Effect.gen(function* () {
               const plugins = yield* PluginSupervisor.Service
-              return { flush: release.open.pipe(Effect.andThen(plugins.flush)) }
+              return { awaitActivation: release.open.pipe(Effect.andThen(plugins.awaitActivation)) }
             }),
           ).pipe(Layer.provide(layer)),
         )
diff --git a/packages/server/src/handlers/plugin.ts b/packages/server/src/handlers/plugin.ts
index 116b5bb59fb..afa45afe2ce 100644
--- a/packages/server/src/handlers/plugin.ts
+++ b/packages/server/src/handlers/plugin.ts
@@ -59,7 +59,7 @@ export const PluginHandler = HttpApiBuilder.group(Api, "server.plugin", (handler
     .handle("plugin.update", (ctx) =>
       Effect.gen(function* () {
         const supervisor = yield* PluginSupervisor.Service
-        yield* supervisor.flush
+        yield* supervisor.awaitActivation
         const plugins = yield* Plugin.Service
         if (
           !(yield* plugins.list()).some(
diff --git a/packages/server/src/handlers/rpc.ts b/packages/server/src/handlers/rpc.ts
index f6a80088171..4cd2dca26e6 100644
--- a/packages/server/src/handlers/rpc.ts
+++ b/packages/server/src/handlers/rpc.ts
@@ -9,7 +9,7 @@ export const RpcHandler = HttpApiBuilder.group(Api, "server.rpc", (handlers) =>
   handlers.handle("rpc.call", ({ params, payload }) =>
     Effect.gen(function* () {
       const supervisor = yield* PluginSupervisor.Service
-      yield* supervisor.flush
+      yield* supervisor.awaitActivation
       const rpc = yield* Rpc.Service
       const output = yield* rpc.call(params.rpcID, params.method, payload.input)
       return output === undefined ? {} : { output }
diff --git a/packages/server/test/rpc.test.ts b/packages/server/test/rpc.test.ts
index 33b2b0b736c..d314b8c0654 100644
--- a/packages/server/test/rpc.test.ts
+++ b/packages/server/test/rpc.test.ts
@@ -48,7 +48,7 @@ const fixture = Effect.fn(function* (plugins: readonly Plugin.Plugin[]) {
     boot: (directory: string) =>
       Effect.gen(function* () {
         const supervisor = yield* PluginSupervisor.Service
-        yield* supervisor.flush
+        yield* supervisor.awaitActivation
       }).pipe(Effect.provide(locations.get(Location.Ref.make({ directory: AbsolutePath.make(directory) })))),
     call: (
       route: string,
diff --git a/packages/simulation/test/simulated-provider.test.ts b/packages/simulation/test/simulated-provider.test.ts
index c6b17038a28..5f5fdb4223e 100644
--- a/packages/simulation/test/simulated-provider.test.ts
+++ b/packages/simulation/test/simulated-provider.test.ts
@@ -250,7 +250,7 @@ test("controls arbitrary tools through scoped SDK overlays", async () => {
           Layer.build(locations.get(Location.Ref.make({ directory: AbsolutePath.make(secondDirectory) }))),
         ])
         yield* Effect.forEach([primary, secondary], (context) =>
-          PluginSupervisor.Service.use((supervisor) => supervisor.flush).pipe(Effect.provide(context)),
+          PluginSupervisor.Service.use((supervisor) => supervisor.awaitActivation).pipe(Effect.provide(context)),
         )
         expect(activations).toBe(2)