diff --git a/src/tui/product-host.test.ts b/src/tui/product-host.test.ts
index 7097cd4b2..106055e77 100644
--- a/src/tui/product-host.test.ts
+++ b/src/tui/product-host.test.ts
@@ -203,6 +203,26 @@ describe("mountProductHost", () => {
     }
   })
 
+  test("session.clear wipes the painted transcript (CL-5612)", async () => {
+    const { host, emitter } = await mountHeadless()
+    try {
+      emitter.emit("event", { type: "user", text: "old prompt" })
+      emitter.emit("event", { type: "assistant", text: "old reply" })
+      expect(host.shell.streamLog.length).toBe(2)
+
+      emitter.emit("session.clear")
+      expect(host.shell.streamLog).toEqual([])
+      expect(host.shell.streamLogBase).toBe(0)
+      expect(host.shell.lineCount).toBe(0)
+
+      // Subsequent turns land on the empty transcript.
+      emitter.emit("event", { type: "user", text: "fresh prompt" })
+      expect(host.shell.streamLog).toEqual([{ role: "user", text: "fresh prompt" }])
+    } finally {
+      host.dispose()
+    }
+  })
+
   test("permission.gate opens the overlay and resolves through the emitter's resolve callback", async () => {
     const { host, emitter } = await mountHeadless()
     try {
@@ -253,6 +273,7 @@ describe("mountProductHost", () => {
     expect(emitter.listenerCount("event")).toBe(1)
     expect(emitter.listenerCount("history.hydrate")).toBe(1)
     expect(emitter.listenerCount("session.title")).toBe(1)
+    expect(emitter.listenerCount("session.clear")).toBe(1)
     expect(emitter.listenerCount("permission.gate")).toBe(1)
     expect(emitter.listenerCount("operator.gate")).toBe(1)
 
@@ -263,6 +284,7 @@ describe("mountProductHost", () => {
     expect(emitter.listenerCount("event")).toBe(0)
     expect(emitter.listenerCount("history.hydrate")).toBe(0)
     expect(emitter.listenerCount("session.title")).toBe(0)
+    expect(emitter.listenerCount("session.clear")).toBe(0)
     expect(emitter.listenerCount("permission.gate")).toBe(0)
     expect(emitter.listenerCount("operator.gate")).toBe(0)
   })
diff --git a/src/tui/product-host.ts b/src/tui/product-host.ts
index d0af6fa1b..8bfa2261c 100644
--- a/src/tui/product-host.ts
+++ b/src/tui/product-host.ts
@@ -39,6 +39,7 @@ import type { PaletteCommand } from "./command-catalog.js"
 import {
   appendObserveStreamRow,
   appendStreamRow,
+  clearTranscript,
   createAppShell,
   paintChrome,
   setChromeZones,
@@ -425,6 +426,7 @@ export async function mountProductHost(
     disposeGates()
     config.eventEmitter.off("history.hydrate", onHistory)
     config.eventEmitter.off("session.title", onTitle)
+    config.eventEmitter.off("session.clear", onSessionClear)
     config.eventEmitter.off("hook", onHook)
     config.eventEmitter.off("mcp.status", onMcpStatus)
     config.eventEmitter.off("permission.grant", onPermissionGrant)
@@ -534,6 +536,14 @@ export async function mountProductHost(
     }
   }
 
+  // /clear and /new rotate the backend session in the runner; the host must
+  // wipe the painted transcript so the screen matches a brand-new session.
+  // The Ink App used to own this unconditionally — OpenTUI regressed it.
+  function onSessionClear(): void {
+    if (disposed) return
+    clearTranscript(shell)
+  }
+
   let currentModels = config.models ?? []
   let currentDescribeModel = config.describeModel
   let openModels: (() => void) | undefined
@@ -629,6 +639,7 @@ export async function mountProductHost(
   config.eventEmitter.on("event", onEvent)
   config.eventEmitter.on("history.hydrate", onHistory)
   config.eventEmitter.on("session.title", onTitle)
+  config.eventEmitter.on("session.clear", onSessionClear)
   config.eventEmitter.on("hook", onHook)
   config.eventEmitter.on("mcp.status", onMcpStatus)
   config.eventEmitter.on("permission.grant", onPermissionGrant)
diff --git a/src/tui/runner.ts b/src/tui/runner.ts
index e8b9062c3..56dd18ed4 100644
--- a/src/tui/runner.ts
+++ b/src/tui/runner.ts
@@ -1657,10 +1657,16 @@ export async function runTUI(initialConfig: Config): Promise<number> {
   // abort handles → child agent.close) before clearing the session store so
   // /clear does not leave orphaned child reactors burning tokens.
   const newSession = (): void => {
-    // The App clears its transcript unconditionally on /clear, so the backend
-    // rotation is always enqueued regardless of contention; the queue serialises
-    // it behind any in-progress op. Sub-agents nest under the new session
-    // automatically because getWorkdirBase reads the live sessionId.
+    // Wipe the painted transcript immediately. The product host listens for
+    // session.clear; the Ink App used to clear its own stream unconditionally
+    // and that path never moved to OpenTUI.
+    emitter.emit("session.clear");
+    // Cancel live workers before rotation so /clear does not leave orphaned
+    // child reactors burning tokens under the old session id.
+    subAgentSessions.cancelAll("Session cleared");
+    // Backend rotation is always enqueued regardless of contention; the queue
+    // serialises it behind any in-progress op. Sub-agents nest under the new
+    // session automatically because getWorkdirBase reads the live sessionId.
     void enqueueOp(async () => {
       try {
         // Tear the old agent down and dispose the recorder before workdir is
diff --git a/src/tui/shell.ts b/src/tui/shell.ts
index 1412a82ff..74f062427 100644
--- a/src/tui/shell.ts
+++ b/src/tui/shell.ts
@@ -2326,6 +2326,43 @@ export function truncateStreamRows(shell: AppShell, length: number): void {
   paintChrome(shell)
 }
 
+/**
+ * Empty the visible transcript for a fresh session (/clear, /new).
+ *
+ * Backend session rotation lives in the runner; this is only the on-screen wipe
+ * the OpenTUI host must own after the Ink App path went away. Observe mode is
+ * dropped first so a child view cannot keep painting into a cleared parent.
+ * Retention base resets so the screen matches a brand-new session, not a window
+ * over an empty retained log with a stale eviction marker.
+ */
+export function clearTranscript(shell: AppShell): void {
+  if (shell.observe !== null) {
+    // Drop observe without the "left observe" system row — the whole log is
+    // about to go and a farewell row would only flash then vanish.
+    shell.observe = null
+    shell.parentStreamLog = null
+    shell.parentStreamLogBase = null
+    let guard = 4
+    while (guard-- > 0 && focusOwner(shell.focus) === "observe") {
+      shell.focus = popFocus(shell.focus)
+    }
+    const frames = shell.focus.frames.filter((f) => f.target !== "observe")
+    if (frames.length !== shell.focus.frames.length) {
+      shell.focus = { frames }
+    }
+    setChromeZones(shell, { agents: null })
+    applyFocus(shell)
+  }
+  shell.streamLog.length = 0
+  shell.streamLogBase = 0
+  shell.lineCount = 0
+  shell.parentStreamLog = null
+  shell.parentStreamLogBase = null
+  repaintTranscriptWindow(shell)
+  paintChrome(shell)
+}
+
+
 /**
  * Identifies a transcript child as the eviction notice rather than a row.
  * Identity, not position or state, is the source of truth: `streamLogBase`