diff --git a/packages/simulation/src/frontend/actions.ts b/packages/simulation/src/frontend/actions.ts
index d03e4a5f75..9e5b7bdead 100644
--- a/packages/simulation/src/frontend/actions.ts
+++ b/packages/simulation/src/frontend/actions.ts
@@ -47,7 +47,7 @@ function hit(renderer: CliRenderer, renderable: Renderable) {
 /**
  * Builds the harness the simulation server drives.
  *
- * When the renderer is the fake simulation renderer, its TestRendererSetup
+ * When the renderer is the headless simulation renderer, its TestRendererSetup
  * provides the supported testing APIs. For the visible terminal renderer the
  * harness falls back to `requestRender` + `idle` and reading the private
  * `currentRenderBuffer`.
diff --git a/packages/simulation/src/frontend/renderer.ts b/packages/simulation/src/frontend/renderer.ts
index 168a8999b6..e973d57a98 100644
--- a/packages/simulation/src/frontend/renderer.ts
+++ b/packages/simulation/src/frontend/renderer.ts
@@ -4,7 +4,7 @@ import { createTestRenderer, type TestRendererSetup } from "@opentui/core/testin
 const setups = new WeakMap<CliRenderer, TestRendererSetup>()
 
 /**
- * Creates the fake simulation renderer: a real CliRenderer backed by an
+ * Creates the headless simulation renderer: a real CliRenderer backed by an
  * in-memory screen buffer instead of a terminal. The TestRendererSetup is
  * kept module-side (keyed by renderer) so the harness can use the supported
  * testing APIs without app code carrying it around.
diff --git a/packages/simulation/src/frontend/server.ts b/packages/simulation/src/frontend/server.ts
index 854b5e9846..d99334d6a2 100644
--- a/packages/simulation/src/frontend/server.ts
+++ b/packages/simulation/src/frontend/server.ts
@@ -15,21 +15,16 @@ function parseRequest(input: string | Buffer) {
   return SimulationProtocol.JsonRpc.decodeRequest(JSON.parse(typeof input === "string" ? input : input.toString()))
 }
 
-async function handle(harness: Harness, request: SimulationProtocol.JsonRpc.Request) {
+async function handle(harness: Harness, request: SimulationProtocol.JsonRpc.Request, headless: boolean) {
   switch (request.method) {
     case "ui.state": {
+      if (headless) await harness.renderOnce()
       const result = SimulationActions.state(harness)
       SimulationTrace.add("ui.state", { elements: result.elements.length, actions: result.actions.length })
       return result
     }
     case "ui.action":
       return SimulationActions.execute(harness, actionParam(request.params))
-    case "ui.render": {
-      await harness.renderOnce()
-      const result = SimulationActions.state(harness)
-      SimulationTrace.add("ui.render", { elements: result.elements.length, actions: result.actions.length })
-      return result
-    }
     case "trace.list":
       return { records: SimulationTrace.list() }
     case "trace.clear":
@@ -41,7 +36,7 @@ async function handle(harness: Harness, request: SimulationProtocol.JsonRpc.Requ
   throw new Error(`Unknown simulation method: ${request.method}`)
 }
 
-export function start(harness: Harness, endpoint: string): Server {
+export function start(harness: Harness, endpoint: string, headless: boolean): Server {
   const url = new URL(endpoint)
   const server = Bun.serve<{ readonly drive: true }>({
     hostname: url.hostname,
@@ -61,7 +56,7 @@ export function start(harness: Harness, endpoint: string): Server {
         let request: SimulationProtocol.JsonRpc.Request | undefined
         try {
           request = parseRequest(message)
-          const result = await handle(harness, request)
+          const result = await handle(harness, request, headless)
           const next = SimulationProtocol.JsonRpc.success(request.id, result)
           if (next) socket.send(JSON.stringify(next))
         } catch (error) {
diff --git a/packages/simulation/src/frontend/simulation.ts b/packages/simulation/src/frontend/simulation.ts
index 96e68e8dca..c2a56ad8c1 100644
--- a/packages/simulation/src/frontend/simulation.ts
+++ b/packages/simulation/src/frontend/simulation.ts
@@ -7,19 +7,18 @@ import { SimulationServer } from "./server"
 /**
  * Drive-mode renderer entry point.
  *
- * Creates the renderer (fake when OPENCODE_DRIVE_RENDERER=fake, the normal
+ * Creates the renderer (headless when OPENCODE_DRIVE_RENDERER=headless, the normal
  * visible renderer otherwise) and starts the UI control
  * server against it. The server stops when the renderer is destroyed, so the
  * caller only manages the renderer lifecycle.
  */
 export async function create(options: CliRendererConfig): Promise<CliRenderer> {
-  const renderer =
-    process.env.OPENCODE_DRIVE_RENDERER === "fake"
-      ? await SimulationRenderer.create(options)
-      : await createCliRenderer(options)
+  const headless = process.env.OPENCODE_DRIVE_RENDERER === "headless"
+  const renderer = headless ? await SimulationRenderer.create(options) : await createCliRenderer(options)
   const server = SimulationServer.start(
     SimulationActions.createHarness(renderer),
     DriveManifest.resolve().endpoints.ui,
+    headless,
   )
   process.stderr.write(`opencode drive ui websocket: ${server.url}\n`)
   renderer.once("destroy", () => server.stop())