diff --git a/src/features/workspace/IntakeFieldControl.test.tsx b/src/features/workspace/IntakeFieldControl.test.tsx
new file mode 100644
index 0000000..259fc25
--- /dev/null
+++ b/src/features/workspace/IntakeFieldControl.test.tsx
@@ -0,0 +1,54 @@
+// @vitest-environment jsdom
+import { cleanup, fireEvent, render, screen } from "@testing-library/react";
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { IntakeFieldControl } from "./IntakeFieldControl";
+
+describe("IntakeFieldControl", () => {
+  afterEach(() => cleanup());
+
+  it("renders a single-line text input when no rows prop is provided", () => {
+    render(
+      <IntakeFieldControl
+        label="Issue summary"
+        value="VPN outage in west region"
+        onChange={vi.fn()}
+      />,
+    );
+
+    const input = screen.getByLabelText("Issue summary") as HTMLInputElement;
+    expect(input.tagName).toBe("INPUT");
+    expect(input.type).toBe("text");
+    expect(input.value).toBe("VPN outage in west region");
+  });
+
+  it("renders a multi-line textarea when rows > 1 and reports new values through onChange", () => {
+    const onChange = vi.fn();
+    render(
+      <IntakeFieldControl
+        label="Symptoms"
+        value="initial"
+        rows={3}
+        onChange={onChange}
+      />,
+    );
+
+    const textarea = screen.getByLabelText("Symptoms") as HTMLTextAreaElement;
+    expect(textarea.tagName).toBe("TEXTAREA");
+    expect(textarea.rows).toBe(3);
+
+    fireEvent.change(textarea, { target: { value: "updated symptoms" } });
+    expect(onChange).toHaveBeenCalledWith("updated symptoms");
+  });
+
+  it("fires onChange with the latest value on single-line edits", () => {
+    const onChange = vi.fn();
+    render(
+      <IntakeFieldControl label="Affected user" value="" onChange={onChange} />,
+    );
+
+    fireEvent.change(screen.getByLabelText("Affected user"), {
+      target: { value: "alice@example.com" },
+    });
+    expect(onChange).toHaveBeenCalledWith("alice@example.com");
+  });
+});
diff --git a/src/features/workspace/IntakeFieldControl.tsx b/src/features/workspace/IntakeFieldControl.tsx
new file mode 100644
index 0000000..bbf1dc4
--- /dev/null
+++ b/src/features/workspace/IntakeFieldControl.tsx
@@ -0,0 +1,74 @@
+import type { NoteAudience } from "../../types/workspace";
+
+export type IntakeField =
+  | "issue"
+  | "environment"
+  | "impact"
+  | "affected_user"
+  | "affected_system"
+  | "affected_site"
+  | "symptoms"
+  | "steps_tried"
+  | "blockers"
+  | "likely_category";
+
+export const NOTE_AUDIENCES: Array<{ id: NoteAudience; label: string }> = [
+  { id: "internal-note", label: "Internal note" },
+  { id: "customer-safe", label: "Customer-safe" },
+  { id: "escalation-note", label: "Escalation note" },
+];
+
+export const INTAKE_FIELDS: Array<{
+  key: IntakeField;
+  label: string;
+  rows?: number;
+}> = [
+  { key: "issue", label: "Issue summary" },
+  { key: "environment", label: "Environment" },
+  { key: "impact", label: "Impact", rows: 2 },
+  { key: "affected_user", label: "Affected user" },
+  { key: "affected_system", label: "Affected system" },
+  { key: "affected_site", label: "Affected site" },
+  { key: "symptoms", label: "Symptoms", rows: 3 },
+  { key: "steps_tried", label: "Steps already tried", rows: 3 },
+  { key: "blockers", label: "Current blocker", rows: 2 },
+  { key: "likely_category", label: "Likely category" },
+];
+
+interface IntakeFieldControlProps {
+  label: string;
+  value: string;
+  rows?: number;
+  onChange: (value: string) => void;
+}
+
+export function IntakeFieldControl({
+  label,
+  value,
+  rows,
+  onChange,
+}: IntakeFieldControlProps) {
+  if (rows && rows > 1) {
+    return (
+      <label className="ticket-workspace-rail__field">
+        <span>{label}</span>
+        <textarea
+          rows={rows}
+          value={value}
+          onChange={(event) => onChange(event.target.value)}
+        />
+      </label>
+    );
+  }
+
+  return (
+    <label className="ticket-workspace-rail__field">
+      <span>{label}</span>
+      <input
+        type="text"
+        value={value}
+        onChange={(event) => onChange(event.target.value)}
+      />
+    </label>
+  );
+}
diff --git a/src/features/workspace/TicketWorkspaceRail.tsx b/src/features/workspace/TicketWorkspaceRail.tsx
index dc50b54..d135297 100644
--- a/src/features/workspace/TicketWorkspaceRail.tsx
+++ b/src/features/workspace/TicketWorkspaceRail.tsx
@@ -16,32 +16,15 @@ import type {
   WorkspaceFavorite,
   WorkspacePersonalization,
 } from "../../types/workspace";
+import { markWorkspaceReady } from "./workspacePerformanceMetrics";
+import {
+  INTAKE_FIELDS,
+  IntakeFieldControl,
+  NOTE_AUDIENCES,
+  type IntakeField,
+} from "./IntakeFieldControl";
 import "./TicketWorkspaceRail.css";
 
-const APP_BOOTSTRAP_START_MARK = "assistsupport:perf:bootstrap-start";
-const TICKET_WORKSPACE_READY_MARK = "assistsupport:perf:ticket-workspace-ready";
-const TICKET_WORKSPACE_READY_MEASURE =
-  "assistsupport:perf:ticket-workspace-ready-ms";
-
-type PerfWindow = Window & {
-  __assistsupportPerf?: {
-    bootstrapStartedAt: number;
-    ticketWorkspaceReadyMs?: number;
-  };
-};
-
-type IntakeField =
-  | "issue"
-  | "environment"
-  | "impact"
-  | "affected_user"
-  | "affected_system"
-  | "affected_site"
-  | "symptoms"
-  | "steps_tried"
-  | "blockers"
-  | "likely_category";
-
 interface TicketWorkspaceRailProps {
   intake: CaseIntake;
   onIntakeChange: (field: IntakeField, value: string) => void;
@@ -90,62 +73,6 @@ interface TicketWorkspaceRailProps {
   currentResponse: string;
 }
 
-const NOTE_AUDIENCES: Array<{ id: NoteAudience; label: string }> = [
-  { id: "internal-note", label: "Internal note" },
-  { id: "customer-safe", label: "Customer-safe" },
-  { id: "escalation-note", label: "Escalation note" },
-];
-
-const INTAKE_FIELDS: Array<{ key: IntakeField; label: string; rows?: number }> =
-  [
-    { key: "issue", label: "Issue summary" },
-    { key: "environment", label: "Environment" },
-    { key: "impact", label: "Impact", rows: 2 },
-    { key: "affected_user", label: "Affected user" },
-    { key: "affected_system", label: "Affected system" },
-    { key: "affected_site", label: "Affected site" },
-    { key: "symptoms", label: "Symptoms", rows: 3 },
-    { key: "steps_tried", label: "Steps already tried", rows: 3 },
-    { key: "blockers", label: "Current blocker", rows: 2 },
-    { key: "likely_category", label: "Likely category" },
-  ];
-
-function IntakeFieldControl({
-  label,
-  value,
-  rows,
-  onChange,
-}: {
-  label: string;
-  value: string;
-  rows?: number;
-  onChange: (value: string) => void;
-}) {
-  if (rows && rows > 1) {
-    return (
-      <label className="ticket-workspace-rail__field">
-        <span>{label}</span>
-        <textarea
-          rows={rows}
-          value={value}
-          onChange={(event) => onChange(event.target.value)}
-        />
-      </label>
-    );
-  }
-
-  return (
-    <label className="ticket-workspace-rail__field">
-      <span>{label}</span>
-      <input
-        type="text"
-        value={value}
-        onChange={(event) => onChange(event.target.value)}
-      />
-    </label>
-  );
-}
-
 export function TicketWorkspaceRail({
   intake,
   onIntakeChange,
@@ -209,35 +136,7 @@ export function TicketWorkspaceRail({
   }, [guidedRunbookSession]);
 
   useEffect(() => {
-    if (
-      typeof window === "undefined" ||
-      typeof window.performance === "undefined"
-    ) {
-      return;
-    }
-
-    const perfWindow = window as PerfWindow;
-    const bootstrapStartedAt =
-      perfWindow.__assistsupportPerf?.bootstrapStartedAt ?? 0;
-    perfWindow.__assistsupportPerf = {
-      ...(perfWindow.__assistsupportPerf ?? { bootstrapStartedAt }),
-      bootstrapStartedAt,
-      ticketWorkspaceReadyMs: Number(
-        (window.performance.now() - bootstrapStartedAt).toFixed(2),
-      ),
-    };
-    window.performance.clearMarks(TICKET_WORKSPACE_READY_MARK);
-    window.performance.clearMeasures(TICKET_WORKSPACE_READY_MEASURE);
-    window.performance.mark(TICKET_WORKSPACE_READY_MARK);
-    try {
-      window.performance.measure(
-        TICKET_WORKSPACE_READY_MEASURE,
-        APP_BOOTSTRAP_START_MARK,
-        TICKET_WORKSPACE_READY_MARK,
-      );
-    } catch {
-      // Keep the workspace usable even if performance marks are unavailable in the current runtime.
-    }
+    markWorkspaceReady();
   }, []);
 
   return (
diff --git a/src/features/workspace/workspacePerformanceMetrics.ts b/src/features/workspace/workspacePerformanceMetrics.ts
new file mode 100644
index 0000000..e8da221
--- /dev/null
+++ b/src/features/workspace/workspacePerformanceMetrics.ts
@@ -0,0 +1,44 @@
+export const APP_BOOTSTRAP_START_MARK = "assistsupport:perf:bootstrap-start";
+export const TICKET_WORKSPACE_READY_MARK =
+  "assistsupport:perf:ticket-workspace-ready";
+export const TICKET_WORKSPACE_READY_MEASURE =
+  "assistsupport:perf:ticket-workspace-ready-ms";
+
+type PerfWindow = Window & {
+  __assistsupportPerf?: {
+    bootstrapStartedAt: number;
+    ticketWorkspaceReadyMs?: number;
+  };
+};
+
+export function markWorkspaceReady(): void {
+  if (
+    typeof window === "undefined" ||
+    typeof window.performance === "undefined"
+  ) {
+    return;
+  }
+
+  const perfWindow = window as PerfWindow;
+  const bootstrapStartedAt =
+    perfWindow.__assistsupportPerf?.bootstrapStartedAt ?? 0;
+  perfWindow.__assistsupportPerf = {
+    ...(perfWindow.__assistsupportPerf ?? { bootstrapStartedAt }),
+    bootstrapStartedAt,
+    ticketWorkspaceReadyMs: Number(
+      (window.performance.now() - bootstrapStartedAt).toFixed(2),
+    ),
+  };
+  window.performance.clearMarks(TICKET_WORKSPACE_READY_MARK);
+  window.performance.clearMeasures(TICKET_WORKSPACE_READY_MEASURE);
+  window.performance.mark(TICKET_WORKSPACE_READY_MARK);
+  try {
+    window.performance.measure(
+      TICKET_WORKSPACE_READY_MEASURE,
+      APP_BOOTSTRAP_START_MARK,
+      TICKET_WORKSPACE_READY_MARK,
+    );
+  } catch {
+    // Keep the workspace usable even if performance marks are unavailable in the current runtime.
+  }
+}