diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7024df5..d9cf7f4 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,15 @@
  * SRP/DRY check: Pass - changelog content is centralized in one file with no duplication across docs.
 -->
 
+## [Version 0.4.37] - 2025-11-06 04:11 UTC
+
+### Added
+- Launched the ARC Agent Workspace with ARC-specific run intake, timeline, conversation, and artifact components powered by the new agent modules.@client/src/pages/arc-agent-workspace.tsx@client/src/components/agent/ArcAgentRunForm.tsx@client/src/components/agent/ArcStageTimeline.tsx@client/src/components/agent/ArcConversationLog.tsx@client/src/components/agent/ArcArtifactPanel.tsx@client/src/components/agent/ArcRunControls.tsx
+- Documented the workspace transition plan for ongoing iterations.@docs/2025-11-06-plan-arc-agent-workspace.md
+
+### Changed
+- Updated navigation, shared types, and agent infrastructure to adopt ARC-focused terminology, stages, and configuration defaults.@client/src/App.tsx@client/src/components/AppNavigation.tsx@client/src/stores/useLuigiWorkspaceStore.ts@shared/luigi-types.ts@server/routes/luigi.ts@server/luigi/executor.ts@server/luigi/openai-sdk-runner.ts@server/config.ts
+
 ## [Version 0.4.36] - 2025-11-06 03:45 UTC
 
 ### Added
diff --git a/client/src/App.tsx b/client/src/App.tsx
index 8939905..72d82a4 100644
--- a/client/src/App.tsx
+++ b/client/src/App.tsx
@@ -1,3 +1,10 @@
+/*
+ * Author: gpt-5-codex
+ * Date: 2025-11-06T04:08:30Z
+ * PURPOSE: Application router with ARC agent workspace route updates.
+ * SRP/DRY check: Pass - maintains route mapping without duplicating page logic.
+ */
+
 import { Switch, Route } from "wouter";
 import { queryClient } from "./lib/queryClient";
 import { QueryClientProvider } from "@tanstack/react-query";
@@ -10,7 +17,7 @@ import Home from "@/pages/home";
 import Battle from "@/pages/battle-chat";
 import CreativeCombat from "./pages/creative-combat";
 import Debate from "@/pages/debate";
-import ResearchSynthesis from "@/pages/research-synthesis";
+import ArcAgentWorkspace from "@/pages/arc-agent-workspace";
 import PlanAssessmentPage from "@/pages/plan-assessment";
 import NotFound from "@/pages/not-found";
 import BillingPage from "@/pages/billing";
@@ -27,7 +34,7 @@ function Router() {
       <Route path="/debate" component={Debate} />
       <Route path="/vixra" component={VixraPage} />
       <Route path="/arc-agi" component={ArcAgiPage} />
-      <Route path="/research-synthesis" component={ResearchSynthesis} />
+      <Route path="/arc-agent" component={ArcAgentWorkspace} />
       <Route path="/plan-assessment" component={PlanAssessmentPage} />
       <Route path="/billing" component={BillingPage} />
       <Route component={NotFound} />
@@ -36,7 +43,6 @@ function Router() {
 }
 
 function App() {
-  // Generate unique favicon for this tab/session
   useSimpleDynamicFavicon();
 
   return (
diff --git a/client/src/components/AppNavigation.tsx b/client/src/components/AppNavigation.tsx
index 4055b4b..b863a4a 100644
--- a/client/src/components/AppNavigation.tsx
+++ b/client/src/components/AppNavigation.tsx
@@ -1,12 +1,10 @@
-/**
- * Author: Claude Code using Sonnet 4
- * Date: 2025-01-14
- * PURPOSE: Modernized AppNavigation component using advanced shadcn/ui components.
- * Uses NavigationMenu, Breadcrumb, Switch, and other shadcn/ui primitives for professional UI.
- * Maintains consistent navigation patterns while improving responsive design.
- * SRP/DRY check: Pass - Single responsibility (navigation), reuses shadcn/ui components
- * shadcn/ui: Pass - Uses NavigationMenu, Breadcrumb, Switch, and other shadcn/ui components
- */
+/**
+ * Author: gpt-5-codex (building on Claude Code using Sonnet 4)
+ * Date: 2025-11-06T04:08:45Z
+ * PURPOSE: AppNavigation component with ARC agent workspace entry using shadcn/ui primitives.
+ * SRP/DRY check: Pass - Single navigation responsibility while extending existing mode registry.
+ * shadcn/ui: Pass - continues leveraging NavigationMenu, Breadcrumb, Switch, and related primitives.
+ */
 
 import { Link, useLocation } from "wouter";
 import { Button } from "@/components/ui/button";
@@ -86,14 +84,14 @@ const navigationModes: NavigationMode[] = [
     description: "Critique a plan across models",
     category: 'advanced'
   },
-  {
-    id: "research-synthesis",
-    name: "Research",
-    path: "/research-synthesis",
-    icon: Users,
-    description: "Collaborative research synthesis",
-    category: 'advanced'
-  },
+  {
+    id: "arc-agent",
+    name: "ARC Workspace",
+    path: "/arc-agent",
+    icon: Users,
+    description: "ARC agent orchestration workspace",
+    category: 'advanced'
+  },
   {
     id: "vixra",
     name: "Vixra",
diff --git a/client/src/components/agent/ArcAgentRunForm.tsx b/client/src/components/agent/ArcAgentRunForm.tsx
new file mode 100644
index 0000000..506f535
--- /dev/null
+++ b/client/src/components/agent/ArcAgentRunForm.tsx
@@ -0,0 +1,224 @@
+/*
+ * Author: gpt-5-codex
+ * Date: 2025-11-06T04:05:00Z
+ * PURPOSE: ARC agent workspace intake form capturing task context and validating ARC grid JSON before launching runs.
+ * SRP/DRY check: Pass - handles only form presentation and payload normalization, delegating persistence to store/hooks.
+ */
+
+import { useState, useEffect } from 'react';
+import { useForm } from 'react-hook-form';
+import { z } from 'zod';
+import { zodResolver } from '@hookform/resolvers/zod';
+import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
+import { Button } from '@/components/ui/button';
+import { Input } from '@/components/ui/input';
+import { Textarea } from '@/components/ui/textarea';
+import { Label } from '@/components/ui/label';
+import { useLuigiWorkspaceStore } from '@/stores/useLuigiWorkspaceStore';
+import type { ArcExample, CreateLuigiRunRequest } from '@shared/luigi-types';
+
+const gridSchema = z
+  .array(z.array(z.number().int().min(0).max(9)).min(1))
+  .min(1, 'ARC grids must contain at least one row.');
+
+const exampleSchema: z.ZodType<ArcExample> = z.object({
+  input: gridSchema,
+  output: gridSchema.optional(),
+});
+
+const trainingExamplesSchema = z
+  .string()
+  .min(5, 'Provide at least one training pair.')
+  .transform((value, ctx) => {
+    try {
+      const parsed = JSON.parse(value) as unknown;
+      const examples = z.array(exampleSchema).min(1).parse(parsed);
+      return examples;
+    } catch (error) {
+      ctx.addIssue({
+        code: z.ZodIssueCode.custom,
+        message:
+          'Training pairs must be valid JSON: an array of { "input": number[][], "output": number[][] } records with digits 0-9.',
+      });
+      return z.NEVER;
+    }
+  });
+
+const evaluationExampleSchema = z
+  .string()
+  .optional()
+  .transform((value, ctx) => {
+    if (!value) return undefined;
+    try {
+      const parsed = JSON.parse(value) as unknown;
+      return exampleSchema.parse(parsed);
+    } catch (error) {
+      ctx.addIssue({
+        code: z.ZodIssueCode.custom,
+        message:
+          'Evaluation grid must be valid JSON describing a single { "input": number[][], "output"?: number[][] } object.',
+      });
+      return z.NEVER;
+    }
+  });
+
+const formSchema = z.object({
+  taskId: z.string().min(3, 'Task ID must be at least 3 characters.'),
+  analysisBrief: z
+    .string()
+    .min(10, 'Describe the analysis goal so the ARC agent understands the mission.'),
+  trainingPairs: trainingExamplesSchema,
+  evaluationInput: evaluationExampleSchema,
+  workspaceNotes: z.string().optional(),
+});
+
+type FormValues = z.input<typeof formSchema>;
+
+export interface ArcAgentRunFormProps {
+  className?: string;
+  isSubmitting?: boolean;
+  onSubmit: (payload: CreateLuigiRunRequest) => void;
+}
+
+export function ArcAgentRunForm({ className, isSubmitting, onSubmit }: ArcAgentRunFormProps) {
+  const formStateSnapshot = useLuigiWorkspaceStore((state) => state.form);
+  const setFormField = useLuigiWorkspaceStore((state) => state.setFormField);
+  const resetForm = useLuigiWorkspaceStore((state) => state.resetForm);
+
+  const [submitError, setSubmitError] = useState<string | undefined>();
+
+  const {
+    register,
+    handleSubmit,
+    reset,
+    formState: { errors },
+  } = useForm<FormValues>({
+    resolver: zodResolver(formSchema),
+    defaultValues: formStateSnapshot,
+  });
+
+  useEffect(() => {
+    reset(formStateSnapshot);
+  }, [formStateSnapshot, reset]);
+
+  const registerField = <K extends keyof FormValues>(field: K) =>
+    register(field, {
+      onChange: (event) => {
+        const value = (event.target as HTMLInputElement | HTMLTextAreaElement).value;
+        setFormField(field, value);
+      },
+    });
+
+  const submit = (values: FormValues) => {
+    setSubmitError(undefined);
+    const parsed = formSchema.safeParse(values);
+    if (!parsed.success) {
+      setSubmitError('Fix validation errors before launching the ARC agent.');
+      return;
+    }
+
+    onSubmit({
+      taskId: parsed.data.taskId.trim(),
+      analysisBrief: parsed.data.analysisBrief.trim(),
+      trainingExamples: parsed.data.trainingPairs,
+      evaluationExample: parsed.data.evaluationInput,
+      workspaceNotes: parsed.data.workspaceNotes?.trim() || undefined,
+    });
+  };
+
+  const handleClear = () => {
+    resetForm();
+    reset({
+      taskId: '',
+      analysisBrief: '',
+      trainingPairs: '',
+      evaluationInput: '',
+      workspaceNotes: '',
+    });
+    setSubmitError(undefined);
+  };
+
+  return (
+    <Card className={className}>
+      <CardHeader>
+        <CardTitle>Launch ARC Agent</CardTitle>
+      </CardHeader>
+      <CardContent>
+        <form onSubmit={handleSubmit(submit)} className="space-y-5">
+          <div className="space-y-2">
+            <Label htmlFor="taskId">ARC Task ID</Label>
+            <Input
+              id="taskId"
+              placeholder="e.g. 0e0a153c"
+              autoComplete="off"
+              {...registerField('taskId')}
+            />
+            {errors.taskId && <p className="text-sm text-red-500">{errors.taskId.message}</p>}
+          </div>
+
+          <div className="space-y-2">
+            <Label htmlFor="analysisBrief">Mission Brief</Label>
+            <Textarea
+              id="analysisBrief"
+              rows={3}
+              placeholder="Summarize the transformation you want the ARC agent to uncover and how to evaluate success."
+              {...registerField('analysisBrief')}
+            />
+            {errors.analysisBrief && (
+              <p className="text-sm text-red-500">{errors.analysisBrief.message}</p>
+            )}
+          </div>
+
+          <div className="space-y-2">
+            <Label htmlFor="trainingPairs">Training Pairs JSON</Label>
+            <Textarea
+              id="trainingPairs"
+              rows={6}
+              placeholder='[
+  { "input": [[0,1],[1,0]], "output": [[1,0],[0,1]] }
+]'
+              {...registerField('trainingPairs')}
+            />
+            {errors.trainingPairs && (
+              <p className="text-sm text-red-500">{errors.trainingPairs.message as string}</p>
+            )}
+          </div>
+
+          <div className="space-y-2">
+            <Label htmlFor="evaluationInput">Evaluation Grid JSON (optional)</Label>
+            <Textarea
+              id="evaluationInput"
+              rows={4}
+              placeholder='{ "input": [[0,2,0],[2,0,2],[0,2,0]] }'
+              {...registerField('evaluationInput')}
+            />
+            {errors.evaluationInput && (
+              <p className="text-sm text-red-500">{errors.evaluationInput.message as string}</p>
+            )}
+          </div>
+
+          <div className="space-y-2">
+            <Label htmlFor="workspaceNotes">Workspace Notes</Label>
+            <Textarea
+              id="workspaceNotes"
+              rows={2}
+              placeholder="Additional hypotheses, tool usage expectations, or dataset references."
+              {...registerField('workspaceNotes')}
+            />
+          </div>
+
+          {submitError && <p className="text-sm text-red-500">{submitError}</p>}
+
+          <div className="flex justify-between gap-3">
+            <Button type="submit" disabled={isSubmitting}>
+              {isSubmitting ? 'Launching…' : 'Launch ARC Agent'}
+            </Button>
+            <Button type="button" variant="ghost" onClick={handleClear}>
+              Clear
+            </Button>
+          </div>
+        </form>
+      </CardContent>
+    </Card>
+  );
+}
diff --git a/client/src/components/agent/ArcArtifactPanel.tsx b/client/src/components/agent/ArcArtifactPanel.tsx
new file mode 100644
index 0000000..615f0aa
--- /dev/null
+++ b/client/src/components/agent/ArcArtifactPanel.tsx
@@ -0,0 +1,92 @@
+/*
+ * Author: gpt-5-codex
+ * Date: 2025-11-06T04:06:30Z
+ * PURPOSE: Present ARC agent artifacts such as markdown briefs and grid outputs.
+ * SRP/DRY check: Pass - stateless artifact browser component.
+ */
+
+import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
+import { Tabs, TabsContent, TabsList, TabsTrigger } from '@/components/ui/tabs';
+import type { LuigiArtifactRecord } from '@shared/luigi-types';
+import { ScrollArea } from '@/components/ui/scroll-area';
+import { cn } from '@/lib/utils';
+
+interface ArcArtifactPanelProps {
+  artifacts: LuigiArtifactRecord[];
+  className?: string;
+}
+
+function renderArtifact(artifact: LuigiArtifactRecord) {
+  switch (artifact.type) {
+    case 'markdown':
+      return (
+        <ScrollArea className="h-[300px]">
+          <pre className="whitespace-pre-wrap text-sm text-foreground">
+            {typeof artifact.data?.markdown === 'string' ? artifact.data.markdown : artifact.description}
+          </pre>
+        </ScrollArea>
+      );
+    case 'json':
+      return (
+        <pre className="h-[300px] overflow-auto rounded bg-muted p-3 text-xs">
+          {JSON.stringify(artifact.data, null, 2)}
+        </pre>
+      );
+    default:
+      return (
+        <div className="text-sm text-muted-foreground">
+          {artifact.description ?? 'Download artifacts from the ARC agent to inspect them.'}
+        </div>
+      );
+  }
+}
+
+export function ArcArtifactPanel({ artifacts, className }: ArcArtifactPanelProps) {
+  if (artifacts.length === 0) {
+    return (
+      <Card className={className}>
+        <CardHeader>
+          <CardTitle>Agent Artifacts</CardTitle>
+        </CardHeader>
+        <CardContent>
+          <p className="text-sm text-muted-foreground">
+            Generated outputs will appear here once the ARC agent emits briefs, grids, or tool outputs.
+          </p>
+        </CardContent>
+      </Card>
+    );
+  }
+
+  return (
+    <Card className={className}>
+      <CardHeader>
+        <CardTitle>Agent Artifacts</CardTitle>
+      </CardHeader>
+      <CardContent className="p-0">
+        <Tabs defaultValue={artifacts[0]?.artifactId} className="w-full">
+          <TabsList className="w-full justify-start overflow-x-auto">
+            {artifacts.map((artifact) => (
+              <TabsTrigger key={artifact.artifactId} value={artifact.artifactId} className="whitespace-nowrap">
+                {artifact.title}
+              </TabsTrigger>
+            ))}
+          </TabsList>
+          {artifacts.map((artifact) => (
+            <TabsContent key={artifact.artifactId} value={artifact.artifactId} className="border-t border-border/60 p-4">
+              <div className="space-y-3">
+                <header className="space-y-1">
+                  <h3 className="text-base font-semibold text-foreground">{artifact.title}</h3>
+                  <p className="text-xs uppercase tracking-wide text-muted-foreground">
+                    Stage: {artifact.stageId} · Type: {artifact.type}
+                  </p>
+                  {artifact.description && <p className="text-sm text-muted-foreground">{artifact.description}</p>}
+                </header>
+                <div className={cn('rounded-md border border-border/60 bg-background p-3')}>{renderArtifact(artifact)}</div>
+              </div>
+            </TabsContent>
+          ))}
+        </Tabs>
+      </CardContent>
+    </Card>
+  );
+}
diff --git a/client/src/components/agent/ArcConversationLog.tsx b/client/src/components/agent/ArcConversationLog.tsx
new file mode 100644
index 0000000..99b5b12
--- /dev/null
+++ b/client/src/components/agent/ArcConversationLog.tsx
@@ -0,0 +1,70 @@
+/*
+ * Author: gpt-5-codex
+ * Date: 2025-11-06T04:06:00Z
+ * PURPOSE: Display ARC agent conversation history with role-aware styling for orchestrator updates.
+ * SRP/DRY check: Pass - renders log from props without side effects.
+ */
+
+import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
+import type { LuigiMessagePayload } from '@shared/luigi-types';
+import { ScrollArea } from '@/components/ui/scroll-area';
+import { cn } from '@/lib/utils';
+
+interface ArcConversationLogProps {
+  messages: LuigiMessagePayload[];
+  className?: string;
+}
+
+const ROLE_LABELS: Record<LuigiMessagePayload['role'], string> = {
+  system: 'System',
+  orchestrator: 'Orchestrator',
+  'stage-lead': 'Stage Lead',
+  agent: 'Agent',
+  tool: 'Tool',
+  user: 'User',
+};
+
+export function ArcConversationLog({ messages, className }: ArcConversationLogProps) {
+  return (
+    <Card className={className}>
+      <CardHeader>
+        <CardTitle>Agent Transcript</CardTitle>
+      </CardHeader>
+      <CardContent className="p-0">
+        <ScrollArea className="h-[420px]">
+          <div className="space-y-4 p-4">
+            {messages.length === 0 && (
+              <p className="text-sm text-muted-foreground">
+                No messages yet. Launch the ARC agent to see orchestrator reasoning and tool calls.
+              </p>
+            )}
+            {messages.map((message) => (
+              <article
+                key={message.messageId}
+                className={cn(
+                  'rounded-md border border-border/60 bg-background p-3 shadow-sm transition-colors',
+                  message.role === 'user' ? 'border-primary/60 bg-primary/10' : undefined
+                )}
+              >
+                <header className="mb-1 flex items-center justify-between text-xs uppercase tracking-wide text-muted-foreground">
+                  <span>
+                    {ROLE_LABELS[message.role]}
+                    {message.agentId ? ` · ${message.agentId}` : ''}
+                    {message.stageId ? ` · ${message.stageId}` : ''}
+                  </span>
+                  <span>{new Date(message.createdAt).toLocaleTimeString()}</span>
+                </header>
+                <pre className="whitespace-pre-wrap text-sm text-foreground">{message.content}</pre>
+                {message.reasoning && (
+                  <pre className="mt-2 whitespace-pre-wrap rounded bg-muted p-2 text-xs text-muted-foreground">
+                    {message.reasoning}
+                  </pre>
+                )}
+              </article>
+            ))}
+          </div>
+        </ScrollArea>
+      </CardContent>
+    </Card>
+  );
+}
diff --git a/client/src/components/agent/ArcRunControls.tsx b/client/src/components/agent/ArcRunControls.tsx
new file mode 100644
index 0000000..3b4933f
--- /dev/null
+++ b/client/src/components/agent/ArcRunControls.tsx
@@ -0,0 +1,57 @@
+/*
+ * Author: gpt-5-codex
+ * Date: 2025-11-06T04:07:00Z
+ * PURPOSE: Provide pause/resume/cancel controls for ARC agent runs with status context.
+ * SRP/DRY check: Pass - exposes control buttons for the current run without owning run state logic.
+ */
+
+import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
+import { Button } from '@/components/ui/button';
+import type { LuigiRunSummary } from '@shared/luigi-types';
+import { Loader2, PauseCircle, PlayCircle, StopCircle } from 'lucide-react';
+
+interface ArcRunControlsProps {
+  run?: LuigiRunSummary;
+  isMutating: boolean;
+  onPause: () => Promise<void> | void;
+  onResume: () => Promise<void> | void;
+  onCancel: () => Promise<void> | void;
+  onRefresh: () => void;
+}
+
+export function ArcRunControls({ run, isMutating, onPause, onResume, onCancel, onRefresh }: ArcRunControlsProps) {
+  const status = run?.status ?? 'idle';
+  const disabled = isMutating || !run;
+
+  return (
+    <Card>
+      <CardHeader>
+        <CardTitle>Run Controls</CardTitle>
+      </CardHeader>
+      <CardContent className="space-y-3 text-sm text-muted-foreground">
+        <div className="flex items-center gap-2 text-xs uppercase text-foreground">
+          <span>Status:</span>
+          <span className="font-semibold">{status}</span>
+          {isMutating && <Loader2 className="h-4 w-4 animate-spin" />}
+        </div>
+        <div className="grid grid-cols-2 gap-2">
+          <Button size="sm" variant="secondary" onClick={onRefresh} disabled={!run}>
+            Refresh
+          </Button>
+          <Button size="sm" variant="outline" onClick={onPause} disabled={disabled || status !== 'running'}>
+            <PauseCircle className="mr-2 h-4 w-4" /> Pause
+          </Button>
+          <Button size="sm" variant="outline" onClick={onResume} disabled={disabled || status !== 'paused'}>
+            <PlayCircle className="mr-2 h-4 w-4" /> Resume
+          </Button>
+          <Button size="sm" variant="destructive" onClick={onCancel} disabled={disabled}>
+            <StopCircle className="mr-2 h-4 w-4" /> Cancel
+          </Button>
+        </div>
+        <p className="text-xs text-muted-foreground">
+          Use these controls to manage the orchestrator if it stalls while exploring transformations.
+        </p>
+      </CardContent>
+    </Card>
+  );
+}
diff --git a/client/src/components/luigi/LuigiStageTimeline.tsx b/client/src/components/agent/ArcStageTimeline.tsx
similarity index 82%
rename from client/src/components/luigi/LuigiStageTimeline.tsx
rename to client/src/components/agent/ArcStageTimeline.tsx
index 28a0cb5..cda49c2 100644
--- a/client/src/components/luigi/LuigiStageTimeline.tsx
+++ b/client/src/components/agent/ArcStageTimeline.tsx
@@ -1,9 +1,8 @@
-/*
- * Author: Codex using GPT-5
- * Date: 2025-10-04T10:19:06Z
- * PURPOSE: Timeline component visualising Luigi stage progression and status badges.
- * SRP/DRY check: Pass - renders stages from provided data without managing state or side effects.
- * shadcn/ui: Pass - uses shadcn Card, ScrollArea, Badge components.
+/*
+ * Author: gpt-5-codex
+ * Date: 2025-11-06T04:05:30Z
+ * PURPOSE: Render ARC agent stage progression with ARC-specific naming and status indicators.
+ * SRP/DRY check: Pass - purely presentational timeline driven by provided run summary data.
  */
 
 import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
@@ -13,7 +12,7 @@ import type { LuigiRunSummary, LuigiStageId } from '@shared/luigi-types';
 import { LUIGI_STAGES } from '@shared/luigi-types';
 import { cn } from '@/lib/utils';
 
-interface LuigiStageTimelineProps {
+interface ArcStageTimelineProps {
   stageMap: LuigiRunSummary['stages'];
   currentStageId?: LuigiStageId | null;
 }
@@ -32,11 +31,11 @@ function statusVariant(status: string): { variant: 'secondary' | 'outline' | 'de
   }
 }
 
-export function LuigiStageTimeline({ stageMap, currentStageId }: LuigiStageTimelineProps) {
+export function ArcStageTimeline({ stageMap, currentStageId }: ArcStageTimelineProps) {
   return (
     <Card className="h-full">
       <CardHeader>
-        <CardTitle>Stage Timeline</CardTitle>
+        <CardTitle>ARC Pipeline</CardTitle>
       </CardHeader>
       <CardContent className="p-0">
         <ScrollArea className="h-[420px]">
@@ -64,7 +63,7 @@ export function LuigiStageTimeline({ stageMap, currentStageId }: LuigiStageTimel
                     {snapshot?.completedAt && (
                       <span>Completed: {new Date(snapshot.completedAt).toLocaleString()}</span>
                     )}
-                    {!snapshot?.startedAt && 'Not started yet'}
+                    {!snapshot?.startedAt && 'Awaiting activation'}
                   </div>
                   {snapshot?.blockingReason && (
                     <p className="mt-2 text-xs text-red-500">{snapshot.blockingReason}</p>
diff --git a/client/src/components/luigi/LuigiArtifactPanel.tsx b/client/src/components/luigi/LuigiArtifactPanel.tsx
deleted file mode 100644
index 5e747ba..0000000
--- a/client/src/components/luigi/LuigiArtifactPanel.tsx
+++ /dev/null
@@ -1,86 +0,0 @@
-/*
- * Author: Codex using GPT-5
- * Date: 2025-10-04T10:19:54Z
- * PURPOSE: Artifact panel grouping Luigi outputs by stage with tabbed navigation.
- * SRP/DRY check: Pass - renders artifacts passed in without fetching or mutating state.
- * shadcn/ui: Pass - uses shadcn Tabs, Card, ScrollArea components.
- */
-
-import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
-import { Tabs, TabsContent, TabsList, TabsTrigger } from '@/components/ui/tabs';
-import { ScrollArea } from '@/components/ui/scroll-area';
-import type { LuigiArtifactRecord } from '@shared/luigi-types';
-
-interface LuigiArtifactPanelProps {
-  artifacts: LuigiArtifactRecord[];
-  className?: string;
-}
-
-function groupArtifacts(artifacts: LuigiArtifactRecord[]): Map<string, LuigiArtifactRecord[]> {
-  const map = new Map<string, LuigiArtifactRecord[]>();
-  artifacts.forEach((artifact) => {
-    const existing = map.get(artifact.stageId) ?? [];
-    existing.push(artifact);
-    map.set(artifact.stageId, existing);
-  });
-  return map;
-}
-
-export function LuigiArtifactPanel({ artifacts, className }: LuigiArtifactPanelProps) {
-  const grouped = groupArtifacts(artifacts);
-  const stages = Array.from(grouped.keys());
-  const defaultStage = stages[0];
-
-  return (
-    <Card className={className}>
-      <CardHeader>
-        <CardTitle>Artifacts</CardTitle>
-      </CardHeader>
-      <CardContent className="p-0">
-        {artifacts.length === 0 ? (
-          <div className="p-6 text-sm text-muted-foreground">Artifacts will appear here as Luigi progresses.</div>
-        ) : (
-          <Tabs defaultValue={defaultStage} className="w-full">
-            <ScrollArea className="w-full">
-              <TabsList className="flex w-full flex-wrap justify-start gap-2 overflow-x-auto p-4">
-                {stages.map((stageId) => (
-                  <TabsTrigger key={stageId} value={stageId} className="text-xs">
-                    {stageId}
-                  </TabsTrigger>
-                ))}
-              </TabsList>
-            </ScrollArea>
-            {stages.map((stageId) => (
-              <TabsContent key={stageId} value={stageId} className="p-4">
-                <div className="space-y-4">
-                  {grouped.get(stageId)!.map((artifact) => (
-                    <div key={artifact.artifactId} className="space-y-2 rounded-md border border-border/60 p-4">
-                      <div className="flex items-center justify-between">
-                        <div>
-                          <h4 className="text-sm font-semibold text-foreground">{artifact.title}</h4>
-                          {artifact.description && (
-                            <p className="text-xs text-muted-foreground">{artifact.description}</p>
-                          )}
-                        </div>
-                        <span className="text-xs uppercase text-muted-foreground">{artifact.type}</span>
-                      </div>
-                      {artifact.data != null ? (
-                        <pre className="max-h-64 overflow-auto rounded bg-muted p-3 text-xs text-muted-foreground">
-                          {JSON.stringify(artifact.data, null, 2)}
-                        </pre>
-                      ) : null}
-                      {artifact.storagePath && (
-                        <p className="text-xs text-muted-foreground">Stored at: {artifact.storagePath}</p>
-                      )}
-                    </div>
-                  ))}
-                </div>
-              </TabsContent>
-            ))}
-          </Tabs>
-        )}
-      </CardContent>
-    </Card>
-  );
-}
-
diff --git a/client/src/components/luigi/LuigiConversationLog.tsx b/client/src/components/luigi/LuigiConversationLog.tsx
deleted file mode 100644
index 417fdb6..0000000
--- a/client/src/components/luigi/LuigiConversationLog.tsx
+++ /dev/null
@@ -1,101 +0,0 @@
-/*
- * Author: Codex using GPT-5
- * Date: 2025-10-04T10:19:35Z
- * PURPOSE: Conversation log rendering Luigi agent/system/user messages with auto-scroll.
- * SRP/DRY check: Pass - purely presentational, no data fetching or state mutations.
- * shadcn/ui: Pass - uses shadcn Card, ScrollArea, Badge, Separator components.
- */
-
-import { useEffect, useRef } from 'react';
-import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
-import { Badge } from '@/components/ui/badge';
-import { ScrollArea } from '@/components/ui/scroll-area';
-import { Separator } from '@/components/ui/separator';
-import type { LuigiMessagePayload } from '@shared/luigi-types';
-
-interface LuigiConversationLogProps {
-  messages: LuigiMessagePayload[];
-  className?: string;
-}
-
-const ROLE_COLORS: Record<LuigiMessagePayload['role'], string> = {
-  system: 'bg-slate-500',
-  orchestrator: 'bg-blue-600',
-  'stage-lead': 'bg-emerald-600',
-  agent: 'bg-purple-600',
-  tool: 'bg-amber-600',
-  user: 'bg-zinc-600',
-};
-
-export function LuigiConversationLog({ messages, className }: LuigiConversationLogProps) {
-  const bottomRef = useRef<HTMLDivElement | null>(null);
-
-  // Add defensive guard to prevent browser extension MutationObserver errors
-  useEffect(() => {
-    if (!bottomRef.current) return;
-    try {
-      bottomRef.current.scrollIntoView({ behavior: 'smooth' });
-    } catch (error) {
-      // Silently ignore scroll errors (browser extensions can interfere)
-      console.debug('Luigi conversation scroll error:', error);
-    }
-  }, [messages]);
-
-  return (
-    <Card className={className}>
-      <CardHeader>
-        <CardTitle>Conversation</CardTitle>
-      </CardHeader>
-      <CardContent className="p-0">
-        <ScrollArea className="h-[420px]">
-          <div
-            className="space-y-4 p-4"
-            data-gramm="false"
-            data-gramm_editor="false"
-            data-enable-grammarly="false"
-            data-lpignore="true"
-            data-form-type="other"
-          >
-            {messages.length === 0 && (
-              <p className="text-sm text-muted-foreground">No activity yet. Launch a Luigi run to begin.</p>
-            )}
-            {messages.map((message) => (
-              <div key={message.messageId} className="space-y-2 rounded-md border border-border/60 p-3">
-                <div className="flex items-center justify-between">
-                  <div className="flex items-center gap-2">
-                    <Badge className={ROLE_COLORS[message.role] ?? 'bg-slate-500'}>
-                      {message.role.toUpperCase()}
-                    </Badge>
-                    {message.agentId && (
-                      <span className="text-xs text-muted-foreground">{message.agentId}</span>
-                    )}
-                    {message.stageId && (
-                      <Badge variant="outline" className="text-xs">
-                        {message.stageId}
-                      </Badge>
-                    )}
-                  </div>
-                  <span className="text-xs text-muted-foreground">
-                    {new Date(message.createdAt).toLocaleString()}
-                  </span>
-                </div>
-                <Separator />
-                <div className="prose prose-sm max-w-none whitespace-pre-wrap text-sm text-foreground">
-                  {message.content}
-                </div>
-                {message.reasoning && (
-                  <div className="rounded-md bg-muted p-2 text-xs text-muted-foreground">
-                    <strong>Reasoning:</strong>
-                    <br />
-                    {message.reasoning}
-                  </div>
-                )}
-              </div>
-            ))}
-            <div ref={bottomRef} />
-          </div>
-        </ScrollArea>
-      </CardContent>
-    </Card>
-  );
-}
diff --git a/client/src/components/luigi/LuigiRunControls.tsx b/client/src/components/luigi/LuigiRunControls.tsx
deleted file mode 100644
index 0ce0ebc..0000000
--- a/client/src/components/luigi/LuigiRunControls.tsx
+++ /dev/null
@@ -1,86 +0,0 @@
-/*
- * Author: Codex using GPT-5
- * Date: 2025-10-04T10:20:19Z
- * PURPOSE: Luigi run control panel offering pause/resume/cancel actions and status summary.
- * SRP/DRY check: Pass - purely renders controls and metadata for a given run.
- * shadcn/ui: Pass - uses shadcn Card, Button, Badge components.
- */
-
-import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
-import { Button } from '@/components/ui/button';
-import { Badge } from '@/components/ui/badge';
-import type { LuigiRunSummary } from '@shared/luigi-types';
-
-interface LuigiRunControlsProps {
-  run?: LuigiRunSummary;
-  isMutating?: boolean;
-  onPause?: () => void;
-  onResume?: () => void;
-  onCancel?: () => void;
-  onRefresh?: () => void;
-}
-
-export function LuigiRunControls({ run, isMutating, onPause, onResume, onCancel, onRefresh }: LuigiRunControlsProps) {
-  return (
-    <Card>
-      <CardHeader>
-        <CardTitle>Run Controls</CardTitle>
-      </CardHeader>
-      <CardContent className="space-y-4">
-        {run ? (
-          <div className="space-y-3">
-            <div className="flex items-center gap-2 text-sm">
-              <span className="text-muted-foreground">Run ID:</span>
-              <span className="font-mono text-xs">{run.id}</span>
-            </div>
-            <div className="flex items-center gap-3 text-sm">
-              <Badge variant="secondary" className="uppercase">{run.status}</Badge>
-              {run.currentStageId && (
-                <Badge variant="outline" className="text-xs">Stage: {run.currentStageId}</Badge>
-              )}
-              {typeof run.totalCostCents === 'number' && (
-                <span className="text-xs text-muted-foreground">
-                  Cost: ${(run.totalCostCents / 100).toFixed(2)}
-                </span>
-              )}
-            </div>
-            <div className="text-xs text-muted-foreground">
-              Updated {new Date(run.updatedAt).toLocaleString()}
-            </div>
-          </div>
-        ) : (
-          <p className="text-sm text-muted-foreground">Launch a run to unlock controls.</p>
-        )}
-        <div className="flex flex-wrap gap-2">
-          <Button
-            type="button"
-            variant="outline"
-            disabled={!run || run.status !== 'running' || isMutating}
-            onClick={onPause}
-          >
-            Pause
-          </Button>
-          <Button
-            type="button"
-            variant="outline"
-            disabled={!run || run.status !== 'paused' || isMutating}
-            onClick={onResume}
-          >
-            Resume
-          </Button>
-          <Button
-            type="button"
-            variant="destructive"
-            disabled={!run || run.status === 'completed' || run.status === 'cancelled' || isMutating}
-            onClick={onCancel}
-          >
-            Cancel
-          </Button>
-          <Button type="button" variant="ghost" disabled={!onRefresh || isMutating} onClick={onRefresh}>
-            Refresh
-          </Button>
-        </div>
-      </CardContent>
-    </Card>
-  );
-}
diff --git a/client/src/components/luigi/LuigiRunForm.tsx b/client/src/components/luigi/LuigiRunForm.tsx
deleted file mode 100644
index 2a9c72d..0000000
--- a/client/src/components/luigi/LuigiRunForm.tsx
+++ /dev/null
@@ -1,143 +0,0 @@
-/*
- * Author: Codex using GPT-5
- * Date: 2025-10-04T10:33:02Z
- * PURPOSE: Luigi mission input form leveraging react-hook-form with Zod validation.
- * SRP/DRY check: Pass - focuses solely on capturing run parameters, emits submit callback.
- * shadcn/ui: Pass - uses shadcn form primitives (Card, Button, Inputs).
- */
-
-import { useEffect } from "react";
-import { useForm } from "react-hook-form";
-import { zodResolver } from "@hookform/resolvers/zod";
-import { z } from "zod";
-import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
-import { Button } from "@/components/ui/button";
-import { Input } from "@/components/ui/input";
-import { Textarea } from "@/components/ui/textarea";
-import { Label } from "@/components/ui/label";
-import { cn } from "@/lib/utils";
-import { useLuigiWorkspaceStore } from "@/stores/useLuigiWorkspaceStore";
-
-const formSchema = z.object({
-  missionName: z.string().min(3, "Name must be at least 3 characters"),
-  objective: z.string().min(5, "Objective must be at least 5 characters"),
-  constraints: z.string().optional(),
-  successCriteria: z.string().optional(),
-  stakeholderNotes: z.string().optional(),
-});
-
-export type LuigiRunFormValues = z.infer<typeof formSchema>;
-
-interface LuigiRunFormProps {
-  className?: string;
-  isSubmitting?: boolean;
-  onSubmit: (values: LuigiRunFormValues) => void;
-}
-
-const INITIAL_VALUES: LuigiRunFormValues = {
-  missionName: "",
-  objective: "",
-  constraints: "",
-  successCriteria: "",
-  stakeholderNotes: "",
-};
-
-export function LuigiRunForm({ className, isSubmitting, onSubmit }: LuigiRunFormProps) {
-  // Use individual selectors to avoid infinite re-renders
-  const form = useLuigiWorkspaceStore((state) => state.form);
-  const setFormField = useLuigiWorkspaceStore((state) => state.setFormField);
-  const resetForm = useLuigiWorkspaceStore((state) => state.resetForm);
-
-  const { register, handleSubmit, reset, formState } = useForm<LuigiRunFormValues>({
-    resolver: zodResolver(formSchema),
-    defaultValues: form ?? INITIAL_VALUES,
-  });
-
-  useEffect(() => {
-    reset(form ?? INITIAL_VALUES);
-  }, [form, reset]);
-
-  const submit = (values: LuigiRunFormValues) => {
-    onSubmit(values);
-  };
-
-  const registerField = <K extends keyof LuigiRunFormValues>(field: K) =>
-    register(field, {
-      onChange: (event) => setFormField(field, (event.target as HTMLInputElement | HTMLTextAreaElement).value),
-    });
-
-  const handleClear = () => {
-    resetForm();
-    reset(INITIAL_VALUES);
-  };
-
-  return (
-    <Card className={cn("space-y-6", className)}>
-      <CardHeader>
-        <CardTitle>Start Luigi Plan</CardTitle>
-      </CardHeader>
-      <CardContent>
-        <form onSubmit={handleSubmit(submit)} className="space-y-5">
-          <div className="space-y-2">
-            <Label htmlFor="missionName">Mission Name</Label>
-            <Input
-              id="missionName"
-              placeholder="Global expansion readiness"
-              {...registerField("missionName")}
-            />
-            {formState.errors.missionName && (
-              <p className="text-sm text-red-500">{formState.errors.missionName.message}</p>
-            )}
-          </div>
-          <div className="space-y-2">
-            <Label htmlFor="objective">Objective</Label>
-            <Textarea
-              id="objective"
-              rows={3}
-              placeholder="Build a cross-regional business plan for the Luigi agents to execute."
-              {...registerField("objective")}
-            />
-            {formState.errors.objective && (
-              <p className="text-sm text-red-500">{formState.errors.objective.message}</p>
-            )}
-          </div>
-          <div className="space-y-2">
-            <Label htmlFor="constraints">Constraints</Label>
-            <Textarea
-              id="constraints"
-              rows={2}
-              placeholder="Budget limited to .5M, launch within Q2."
-              {...registerField("constraints")}
-            />
-          </div>
-          <div className="space-y-2">
-            <Label htmlFor="successCriteria">Success Criteria</Label>
-            <Textarea
-              id="successCriteria"
-              rows={2}
-              placeholder="Operational readiness score >= 90, stakeholder buy-in across 4 functions."
-              {...registerField("successCriteria")}
-            />
-          </div>
-          <div className="space-y-2">
-            <Label htmlFor="stakeholderNotes">Stakeholder Notes</Label>
-            <Textarea
-              id="stakeholderNotes"
-              rows={2}
-              placeholder="CEO wants emphasis on PMO structure and governance."
-              {...registerField("stakeholderNotes")}
-            />
-          </div>
-          <div className="flex justify-between gap-3">
-            <Button type="submit" disabled={isSubmitting}>
-              {isSubmitting ? "Launching…" : "Launch Luigi Pipeline"}
-            </Button>
-            <Button type="button" variant="ghost" onClick={handleClear}>
-              Clear
-            </Button>
-          </div>
-        </form>
-      </CardContent>
-    </Card>
-  );
-}
diff --git a/client/src/hooks/useLuigiApi.ts b/client/src/hooks/useLuigiApi.ts
index 8d2fd75..9db0c06 100644
--- a/client/src/hooks/useLuigiApi.ts
+++ b/client/src/hooks/useLuigiApi.ts
@@ -1,8 +1,8 @@
-/*
- * Author: Codex using GPT-5
- * Date: 2025-10-04T10:34:01Z
- * PURPOSE: Luigi API hooks built on TanStack Query for run lifecycle, messages, artifacts, and controls.
- * SRP/DRY check: Pass - centralizes Luigi HTTP calls so components reuse consistent logic.
+/*
+ * Author: gpt-5-codex (evolving prior GPT-5 Codex hooks)
+ * Date: 2025-11-06T04:11:00Z
+ * PURPOSE: ARC agent API hooks built on TanStack Query for run lifecycle, messages, artifacts, and controls.
+ * SRP/DRY check: Pass - centralizes ARC agent HTTP calls for reuse across workspace components.
  * shadcn/ui: Pass - hooks only, no UI elements.
  */
 
diff --git a/client/src/pages/research-synthesis.tsx b/client/src/pages/arc-agent-workspace.tsx
similarity index 68%
rename from client/src/pages/research-synthesis.tsx
rename to client/src/pages/arc-agent-workspace.tsx
index 4cb7621..15f2d43 100644
--- a/client/src/pages/research-synthesis.tsx
+++ b/client/src/pages/arc-agent-workspace.tsx
@@ -1,20 +1,19 @@
 /*
- * Author: Codex using GPT-5
- * Date: 2025-10-04T10:23:48Z
- * PURPOSE: Luigi business plan workspace page integrating form, timeline, conversation, and artifacts with live agents.
- * SRP/DRY check: Pass - composes existing Luigi components and hooks without duplicating logic.
- * shadcn/ui: Pass - uses existing shadcn/ui primitives throughout.
+ * Author: gpt-5-codex
+ * Date: 2025-11-06T04:08:00Z
+ * PURPOSE: ARC agent workspace page orchestrating ARC puzzle runs with OpenAI Agents-powered pipeline.
+ * SRP/DRY check: Pass - coordinates ARC workspace components and hooks without duplicating logic.
  */
 
-import { useEffect, useMemo, useState } from "react";
-import { AppNavigation } from "@/components/AppNavigation";
-import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
-import { LuigiRunForm, type LuigiRunFormValues } from "@/components/luigi/LuigiRunForm";
-import { LuigiStageTimeline } from "@/components/luigi/LuigiStageTimeline";
-import { LuigiConversationLog } from "@/components/luigi/LuigiConversationLog";
-import { LuigiArtifactPanel } from "@/components/luigi/LuigiArtifactPanel";
-import { LuigiRunControls } from "@/components/luigi/LuigiRunControls";
-import { useLuigiWorkspaceStore } from "@/stores/useLuigiWorkspaceStore";
+import { useEffect, useMemo, useState } from 'react';
+import { AppNavigation } from '@/components/AppNavigation';
+import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
+import { ArcAgentRunForm } from '@/components/agent/ArcAgentRunForm';
+import { ArcStageTimeline } from '@/components/agent/ArcStageTimeline';
+import { ArcConversationLog } from '@/components/agent/ArcConversationLog';
+import { ArcArtifactPanel } from '@/components/agent/ArcArtifactPanel';
+import { ArcRunControls } from '@/components/agent/ArcRunControls';
+import { useLuigiWorkspaceStore } from '@/stores/useLuigiWorkspaceStore';
 import {
   useCreateLuigiRun,
   useLuigiRun,
@@ -24,16 +23,16 @@ import {
   usePauseLuigiRun,
   useResumeLuigiRun,
   useCancelLuigiRun,
-} from "@/hooks/useLuigiApi";
-import { Alert, AlertDescription, AlertTitle } from "@/components/ui/alert";
-import { Textarea } from "@/components/ui/textarea";
-import { Button } from "@/components/ui/button";
-import { useToast } from "@/hooks/use-toast";
-import { Loader2 } from "lucide-react";
-import type { LuigiRunSummary } from "@shared/luigi-types";
+} from '@/hooks/useLuigiApi';
+import { Alert, AlertDescription, AlertTitle } from '@/components/ui/alert';
+import { Textarea } from '@/components/ui/textarea';
+import { Button } from '@/components/ui/button';
+import { useToast } from '@/hooks/use-toast';
+import { Loader2 } from 'lucide-react';
+import type { LuigiRunSummary } from '@shared/luigi-types';
+import type { CreateLuigiRunRequest } from '@shared/luigi-types';
 
-export default function ResearchSynthesis() {
-  // Use individual selectors to avoid infinite re-renders
+export default function ArcAgentWorkspace() {
   const activeRunId = useLuigiWorkspaceStore((state) => state.activeRunId);
   const runSummary = useLuigiWorkspaceStore((state) => state.runSummary);
   const stageMap = useLuigiWorkspaceStore((state) => state.stageMap);
@@ -47,7 +46,7 @@ export default function ResearchSynthesis() {
   const setError = useLuigiWorkspaceStore((state) => state.setError);
 
   const { toast } = useToast();
-  const [replyDraft, setReplyDraft] = useState("");
+  const [replyDraft, setReplyDraft] = useState('');
 
   const createRun = useCreateLuigiRun();
   const pauseRun = usePauseLuigiRun();
@@ -64,7 +63,7 @@ export default function ResearchSynthesis() {
       setRunContext(runQuery.data.run);
     }
     if (runQuery.error) {
-      setError(runQuery.error instanceof Error ? runQuery.error.message : "Failed to load run");
+      setError(runQuery.error instanceof Error ? runQuery.error.message : 'Failed to load run');
     }
   }, [runQuery.data, runQuery.error, setRunContext, setError]);
 
@@ -80,18 +79,21 @@ export default function ResearchSynthesis() {
     }
   }, [artifactsQuery.data, setRunContext]);
 
-  const handleCreateRun = async (values: LuigiRunFormValues) => {
+  const handleCreateRun = async (payload: CreateLuigiRunRequest) => {
     setSubmitting(true);
     try {
-      const response = await createRun.mutateAsync(values);
+      const response = await createRun.mutateAsync(payload);
       setActiveRunId(response.run.id);
       setRunContext(response.run, [], []);
       setError(undefined);
-      toast({ title: "Luigi pipeline launched", description: "Agents are preparing the business plan." });
+      toast({
+        title: 'ARC agent launched',
+        description: 'The ARC orchestrator is analysing training grids.',
+      });
     } catch (err) {
-      const message = err instanceof Error ? err.message : "Failed to launch Luigi pipeline";
+      const message = err instanceof Error ? err.message : 'Failed to launch ARC agent';
       setError(message);
-      toast({ title: "Launch failed", description: message, variant: "destructive" });
+      toast({ title: 'Launch failed', description: message, variant: 'destructive' });
     } finally {
       setSubmitting(false);
     }
@@ -113,18 +115,18 @@ export default function ResearchSynthesis() {
     if (!activeRunId) return;
     const response = await cancelRun.mutateAsync(activeRunId);
     setRunContext(response.run);
-    toast({ title: "Run cancelled", description: "Luigi run marked as cancelled." });
+    toast({ title: 'Run cancelled', description: 'ARC agent run cancelled.' });
   };
 
   const handleReply = async () => {
     if (!activeRunId || !replyDraft.trim()) return;
     try {
       await sendReply.mutateAsync({ runId: activeRunId, content: replyDraft.trim() });
-      setReplyDraft("");
-      toast({ title: "Reply sent", description: "Luigi orchestrator notified." });
-    } catch (error) {
-      const message = error instanceof Error ? error.message : "Failed to send reply";
-      toast({ title: "Reply failed", description: message, variant: "destructive" });
+      setReplyDraft('');
+      toast({ title: 'Reply sent', description: 'Feedback shared with the ARC orchestrator.' });
+    } catch (sendError) {
+      const message = sendError instanceof Error ? sendError.message : 'Failed to send reply';
+      toast({ title: 'Reply failed', description: message, variant: 'destructive' });
     }
   };
 
@@ -137,21 +139,18 @@ export default function ResearchSynthesis() {
 
   return (
     <div className="min-h-screen bg-muted/10">
-      <AppNavigation
-        title="Luigi Business Plan Workspace"
-        subtitle="Coordinate the Luigi agent federation to assemble a full execution plan"
-      />
+      <AppNavigation title="ARC Agent Workspace" subtitle="Coordinate an ARC-solving agent federation" />
       <div className="mx-auto w-full max-w-7xl space-y-6 px-4 py-6">
         {error && (
           <Alert variant="destructive">
-            <AlertTitle>Workflow Issue</AlertTitle>
+            <AlertTitle>Workspace Issue</AlertTitle>
             <AlertDescription>{error}</AlertDescription>
           </Alert>
         )}
         <div className="grid gap-6 xl:grid-cols-3">
           <div className="space-y-6">
-            <LuigiRunForm isSubmitting={isSubmitting || createRun.isPending} onSubmit={handleCreateRun} />
-            <LuigiRunControls
+            <ArcAgentRunForm isSubmitting={isSubmitting || createRun.isPending} onSubmit={handleCreateRun} />
+            <ArcRunControls
               run={runSummary}
               isMutating={isMutating}
               onPause={handlePause}
@@ -167,7 +166,7 @@ export default function ResearchSynthesis() {
             />
           </div>
           <div className="space-y-6">
-            <LuigiStageTimeline stageMap={stageMapWithFallback} currentStageId={runSummary?.currentStageId ?? null} />
+            <ArcStageTimeline stageMap={stageMapWithFallback} currentStageId={runSummary?.currentStageId ?? null} />
             <StatusCard
               run={runSummary}
               isLoading={runQuery.isLoading}
@@ -176,8 +175,8 @@ export default function ResearchSynthesis() {
             />
           </div>
           <div className="space-y-6">
-            <LuigiConversationLog messages={messages} />
-            <LuigiArtifactPanel artifacts={artifacts} />
+            <ArcConversationLog messages={messages} />
+            <ArcArtifactPanel artifacts={artifacts} />
           </div>
         </div>
       </div>
@@ -196,11 +195,11 @@ function CardReply({ disabled, value, onChange, onSubmit }: CardReplyProps) {
   return (
     <Card>
       <CardHeader>
-        <CardTitle>User Reply</CardTitle>
+        <CardTitle>User Feedback</CardTitle>
       </CardHeader>
       <CardContent className="space-y-3">
         <Textarea
-          placeholder="Provide additional guidance or clarifications for the Luigi orchestrator."
+          placeholder="Suggest new hypotheses or highlight overlooked grid relationships for the ARC agent."
           value={value}
           onChange={(event) => onChange(event.target.value)}
           disabled={disabled}
@@ -253,10 +252,9 @@ function StatusCard({ run, isLoading, messageCount, artifactCount }: StatusCardP
           <span className="font-medium text-foreground">{artifactCount}</span>
         </div>
         <div className="text-xs text-muted-foreground">
-          {run ? `Updated ${new Date(run.updatedAt).toLocaleString()}` : 'Launch a run to begin tracking.'}
+          {run ? `Updated ${new Date(run.updatedAt).toLocaleString()}` : 'Launch a run to start tracking.'}
         </div>
       </CardContent>
     </Card>
   );
 }
-
diff --git a/client/src/stores/useLuigiWorkspaceStore.ts b/client/src/stores/useLuigiWorkspaceStore.ts
index 81696f8..46ec1f6 100644
--- a/client/src/stores/useLuigiWorkspaceStore.ts
+++ b/client/src/stores/useLuigiWorkspaceStore.ts
@@ -1,9 +1,8 @@
 /*
- * Author: Codex using GPT-5
- * Date: 2025-10-04T10:17:36Z
- * PURPOSE: Zustand store managing Luigi workspace form state, active run context, and UI flags.
- * SRP/DRY check: Pass - isolates Luigi workspace state management reused across page/components.
- * shadcn/ui: Pass - store only, no UI elements.
+ * Author: gpt-5-codex
+ * Date: 2025-11-06T04:07:30Z
+ * PURPOSE: Zustand store managing ARC agent workspace form state and run context.
+ * SRP/DRY check: Pass - isolates workspace state management for reuse across workspace components.
  */
 
 import { create } from 'zustand';
@@ -16,11 +15,11 @@ import type {
 } from '@shared/luigi-types';
 
 export interface LuigiFormState {
-  missionName: string;
-  objective: string;
-  constraints?: string;
-  successCriteria?: string;
-  stakeholderNotes?: string;
+  taskId: string;
+  analysisBrief: string;
+  trainingPairs: string;
+  evaluationInput: string;
+  workspaceNotes: string;
 }
 
 export type LuigiStageSnapshot = LuigiStageState;
@@ -47,11 +46,11 @@ interface LuigiWorkspaceState {
 }
 
 const defaultForm: LuigiFormState = {
-  missionName: '',
-  objective: '',
-  constraints: '',
-  successCriteria: '',
-  stakeholderNotes: '',
+  taskId: '',
+  analysisBrief: '',
+  trainingPairs: '',
+  evaluationInput: '',
+  workspaceNotes: '',
 };
 
 export const useLuigiWorkspaceStore = create<LuigiWorkspaceState>((set) => ({
diff --git a/docs/2025-11-06-plan-arc-agent-workspace.md b/docs/2025-11-06-plan-arc-agent-workspace.md
new file mode 100644
index 0000000..80bb790
--- /dev/null
+++ b/docs/2025-11-06-plan-arc-agent-workspace.md
@@ -0,0 +1,37 @@
+<!--
+ * Author: gpt-5-codex
+ * Date: 2025-11-06T03:58:00Z
+ * PURPOSE: Outline plan for transforming research synthesis page into ARC agent workspace leveraging Luigi agent stack.
+ * SRP/DRY check: Pass - planning document only, no code duplication.
+-->
+# Plan: ARC Agent Workspace Transition
+
+## Goal
+Reposition the former research synthesis surface into a production-ready ARC agent workspace that orchestrates ARC puzzle solving via the new OpenAI Agents-powered Luigi stack.
+
+## Tasks
+1. **Rename Page & Navigation**
+   - Replace `/research-synthesis` route and navigation copy with `/arc-agent` labeled "ARC Agent Workspace".
+   - Update page component filename to reflect new purpose.
+
+2. **Redesign Workspace Form**
+   - Introduce ARC-centric inputs (task ID, training pairs JSON, evaluation grid, workspace goals, notes).
+   - Validate JSON structure client-side to keep submissions clean.
+   - Map cleaned payload into Luigi create-run request.
+
+3. **Adapt Store & Hooks**
+   - Update workspace store types/defaults for new fields.
+   - Ensure run submission and state transitions remain intact using existing Luigi hooks.
+
+4. **Server Contract Updates**
+   - Update shared Luigi types and server validation schema to accept ARC payload.
+   - Expand executor prompt builder to include structured ARC puzzle context for orchestrator.
+   - Adjust stage catalogue to ARC solving phases for accurate timeline rendering.
+
+5. **UI Copy & Telemetry**
+   - Refresh hero copy, status cards, and reply placeholders to reference ARC agent operations.
+   - Keep timeline, conversation, and artifact panels but ensure messaging matches ARC nomenclature.
+
+6. **Documentation & Changelog**
+   - Record changes in CHANGELOG with semantic version bump.
+   - Summarize workspace purpose shift in docs if needed.
diff --git a/server/config.ts b/server/config.ts
index 507c272..6a9cb7e 100644
--- a/server/config.ts
+++ b/server/config.ts
@@ -1,9 +1,8 @@
 /*
- *
- * Author: GPT-5 Codex
- * Date: 2025-10-17 and 14:18
- * PURPOSE: Centralized configuration loader; update ensures Helmet/CORS default on only in production while documenting hobby overrides; touches server/index.ts consumers.
- * SRP/DRY check: Pass - config remains single source for settings; confirmed no duplicate loaders exist elsewhere.
+ * Author: gpt-5-codex (extending prior GPT-5 Codex work)
+ * Date: 2025-11-06T04:10:45Z
+ * PURPOSE: Centralized configuration loader with ARC orchestrator defaults.
+ * SRP/DRY check: Pass - remains the single configuration authority for the server.
  */
 
 /**
@@ -160,7 +159,7 @@ export function loadConfig(): AppConfig {
     },
 
     luigi: {
-      orchestratorAgentId: process.env.LUIGI_ORCHESTRATOR_ID || "luigi-master-orchestrator",
+      orchestratorAgentId: process.env.LUIGI_ORCHESTRATOR_ID || "arc-master-orchestrator",
       agentRunnerBaseUrl: process.env.AGENT_RUNNER_BASE_URL || "http://localhost:8700",
       agentRunnerApiKey: process.env.AGENT_RUNNER_API_KEY,
       agentMode: (process.env.LUIGI_AGENT_MODE === 'sdk' ? 'sdk' : 'rest') as LuigiAgentMode,
diff --git a/server/luigi/executor.ts b/server/luigi/executor.ts
index 251a822..57d16a9 100644
--- a/server/luigi/executor.ts
+++ b/server/luigi/executor.ts
@@ -1,46 +1,75 @@
 /*
- * Author: Codex using GPT-5
- * Date: 2025-10-04T10:28:15Z
- * PURPOSE: Luigi executor service orchestrating agent runs via external REST agent runner.
- * SRP/DRY check: Pass - encapsulates Luigi run lifecycle without touching routing or UI concerns.
- * shadcn/ui: Pass - backend only.
+ * Author: gpt-5-codex
+ * Date: 2025-11-06T04:10:00Z
+ * PURPOSE: ARC agent executor orchestrating runs via REST or OpenAI Agents SDK pathways.
+ * SRP/DRY check: Pass - encapsulates run lifecycle while delegating transport and storage responsibilities.
  */
 
 import { callAgentByRest, type AgentRunRequest, type AgentRunResponse } from "../services/agent-runner";
 import { runLuigiOrchestratorWithSdk, type LuigiSdkRunOptions } from "./openai-sdk-runner";
 import { storage } from "../storage";
 import type { LuigiRun, LuigiMessage, LuigiArtifact } from "@shared/schema";
-import type { LuigiRunStatus, LuigiStageId, LuigiStageStatus } from "@shared/luigi-types";
+import type { LuigiRunStatus, LuigiStageId, LuigiStageStatus, ArcExample } from "@shared/luigi-types";
 import { LUIGI_STAGES } from "@shared/luigi-types";
 
 const VALID_STAGE_IDS = new Set<string>(LUIGI_STAGES.map((stage) => stage.id));
-const DEFAULT_STAGE_ID = (LUIGI_STAGES[0]?.id ?? 'start-time-task') as LuigiStageId;
+const DEFAULT_STAGE_ID = (LUIGI_STAGES[0]?.id ?? "ingest-arc-task") as LuigiStageId;
 
 function asLuigiStageId(value: unknown): LuigiStageId | null {
-  if (typeof value !== 'string') {
+  if (typeof value !== "string") {
     return null;
   }
   return VALID_STAGE_IDS.has(value) ? (value as LuigiStageId) : null;
 }
 
 function normalizeArtifactData(data: unknown): Record<string, unknown> | undefined {
-  if (data === null || typeof data === 'undefined') {
+  if (data === null || typeof data === "undefined") {
     return undefined;
   }
 
-  if (typeof data === 'object' && !Array.isArray(data)) {
+  if (typeof data === "object" && !Array.isArray(data)) {
     return data as Record<string, unknown>;
   }
 
   return { value: data };
 }
 
+function stringifyExamples(examples: ArcExample[]): string {
+  return JSON.stringify(examples, null, 2);
+}
+
+function stringifyExample(example?: ArcExample): string | null {
+  if (!example) return null;
+  return JSON.stringify(example, null, 2);
+}
+
+function parseExamples(raw?: string | null): ArcExample[] {
+  if (!raw) return [];
+  try {
+    const parsed = JSON.parse(raw) as unknown;
+    if (!Array.isArray(parsed)) return [];
+    return parsed as ArcExample[];
+  } catch {
+    return [];
+  }
+}
+
+function parseExample(raw?: string | null): ArcExample | undefined {
+  if (!raw) return undefined;
+  try {
+    const parsed = JSON.parse(raw) as ArcExample;
+    return parsed;
+  } catch {
+    return undefined;
+  }
+}
+
 export interface LuigiRunParams {
-  missionName: string;
-  objective: string;
-  constraints?: string;
-  successCriteria?: string;
-  stakeholderNotes?: string;
+  taskId: string;
+  analysisBrief: string;
+  trainingExamples: ArcExample[];
+  evaluationExample?: ArcExample;
+  workspaceNotes?: string;
 }
 
 export interface LuigiExecutorOptions {
@@ -86,11 +115,11 @@ export class LuigiExecutor {
 
   async createRun(params: LuigiRunParams): Promise<LuigiRunContext> {
     const run = await storage.createLuigiRun({
-      missionName: params.missionName,
-      objective: params.objective,
-      constraints: params.constraints ?? null,
-      successCriteria: params.successCriteria ?? null,
-      stakeholderNotes: params.stakeholderNotes ?? null,
+      missionName: params.taskId,
+      objective: params.analysisBrief,
+      constraints: stringifyExamples(params.trainingExamples),
+      successCriteria: stringifyExample(params.evaluationExample),
+      stakeholderNotes: params.workspaceNotes ?? null,
       userPrompt: this.buildPrompt(params),
       status: "pending",
       currentStageId: null,
@@ -121,7 +150,7 @@ export class LuigiExecutor {
         await storage.appendLuigiMessage({
           runId,
           role: "system",
-          content: `Luigi run failed: ${error instanceof Error ? error.message : String(error)}`,
+          content: `ARC agent run failed: ${error instanceof Error ? error.message : String(error)}`,
         });
       });
     }
@@ -136,13 +165,23 @@ export class LuigiExecutor {
     await storage.appendLuigiMessage({
       runId,
       role: "system",
-      content: "Luigi orchestrator launching...",
+      content: "ARC orchestrator launching...",
     });
 
+    const trainingExamples = parseExamples(run.constraints);
+    const evaluationExample = parseExample(run.successCriteria);
+
     if (this.agentMode === 'sdk') {
       const response = await runLuigiOrchestratorWithSdk({
         run,
         options: this.sdkOptions,
+        arcContext: {
+          taskId: run.missionName,
+          analysisBrief: run.objective,
+          trainingExamples,
+          evaluationExample,
+          workspaceNotes: run.stakeholderNotes ?? undefined,
+        },
       });
       await this.handleAgentResponse(runId, response);
       return;
@@ -152,11 +191,12 @@ export class LuigiExecutor {
       agentId: this.orchestratorAgentId,
       input: {
         runId,
-        missionName: run.missionName,
-        objective: run.objective,
-        constraints: run.constraints ?? undefined,
-        successCriteria: run.successCriteria ?? undefined,
-        stakeholderNotes: run.stakeholderNotes ?? undefined,
+        taskId: run.missionName,
+        analysisBrief: run.objective,
+        trainingExamples,
+        evaluationExample,
+        workspaceNotes: run.stakeholderNotes ?? undefined,
+        userPrompt: run.userPrompt,
       },
     };
 
@@ -218,78 +258,11 @@ export class LuigiExecutor {
           type: artifact.type,
           title: artifact.title,
           description: artifact.description,
+          storagePath: artifact.storagePath,
           data: normalizeArtifactData(artifact.data),
         });
       }
     }
-
-    if (response.nextAction === "await_user") {
-      await storage.appendLuigiMessage({
-        runId,
-        role: "system",
-        content: "Luigi orchestrator is awaiting user input.",
-      });
-    }
-  }
-
-  async submitUserReply(runId: string, content: string): Promise<LuigiMessage> {
-    const message = await storage.appendLuigiMessage({
-      runId,
-      role: "user",
-      content,
-    });
-
-    if (this.agentMode === 'sdk') {
-      const run = await storage.getLuigiRun(runId);
-      if (!run) {
-        throw new Error(`Luigi run ${runId} not found while processing user reply`);
-      }
-      const response = await runLuigiOrchestratorWithSdk({
-        run,
-        userReply: content,
-        options: this.sdkOptions,
-      });
-      await this.handleAgentResponse(runId, response);
-      return message;
-    }
-
-    const payload: AgentRunRequest = {
-      agentId: this.orchestratorAgentId,
-      input: { runId, userReply: content },
-    };
-
-    await callAgentByRest(payload, {
-      baseUrl: this.restBaseUrl,
-      apiKey: this.restApiKey,
-      timeoutMs: this.timeoutMs,
-    });
-
-    return message;
-  }
-
-  async pauseRun(runId: string): Promise<LuigiRunContext> {
-    await storage.updateLuigiRun(runId, { status: "paused", updatedAt: new Date() });
-    return this.fetchContext(runId);
-  }
-
-  async resumeRun(runId: string): Promise<LuigiRunContext> {
-    await storage.updateLuigiRun(runId, { status: "running", updatedAt: new Date() });
-    void this.launchOrchestrator(runId);
-    return this.fetchContext(runId);
-  }
-
-  async cancelRun(runId: string): Promise<LuigiRunContext> {
-    await storage.updateLuigiRun(runId, {
-      status: "cancelled",
-      completedAt: new Date(),
-      updatedAt: new Date(),
-    });
-    await storage.appendLuigiMessage({
-      runId,
-      role: "system",
-      content: "Luigi run cancelled by user.",
-    });
-    return this.fetchContext(runId);
   }
 
   async fetchContext(runId: string): Promise<LuigiRunContext> {
@@ -297,6 +270,7 @@ export class LuigiExecutor {
     if (!run) {
       throw new Error(`Luigi run ${runId} not found`);
     }
+
     const [messages, artifacts] = await Promise.all([
       storage.getLuigiMessages(runId),
       storage.getLuigiArtifacts(runId),
@@ -306,13 +280,26 @@ export class LuigiExecutor {
   }
 
   private buildPrompt(params: LuigiRunParams): string {
-    return [
-      `Mission Name: ${params.missionName}`,
-      `Objective: ${params.objective}`,
-      params.constraints ? `Constraints: ${params.constraints}` : null,
-      params.successCriteria ? `Success Criteria: ${params.successCriteria}` : null,
-      params.stakeholderNotes ? `Stakeholder Notes: ${params.stakeholderNotes}` : null,
-    ].filter(Boolean).join('\n');
+    const sections = [
+      `ARC Task ID: ${params.taskId}`,
+      `Mission Brief: ${params.analysisBrief}`,
+      `Training Examples (JSON):\n${stringifyExamples(params.trainingExamples)}`,
+    ];
+
+    if (params.evaluationExample) {
+      sections.push(`Evaluation Example (JSON):\n${stringifyExample(params.evaluationExample)}`);
+    }
+
+    if (params.workspaceNotes) {
+      sections.push(`Workspace Notes: ${params.workspaceNotes}`);
+    }
+
+    sections.push(
+      'Guidance: Identify transformation rules, validate against training pairs, generalize to evaluation inputs, '
+        + 'and emit final predictions alongside reasoning.'
+    );
+
+    return sections.join('\n\n');
   }
 
   private initializeStageMap(): StageMap {
diff --git a/server/luigi/openai-sdk-runner.ts b/server/luigi/openai-sdk-runner.ts
index 06d6fd0..4212916 100644
--- a/server/luigi/openai-sdk-runner.ts
+++ b/server/luigi/openai-sdk-runner.ts
@@ -1,14 +1,12 @@
 /**
- * Author: ChatGPT-4.1
- * Date: 2025-10-24T23:05:00Z
- * PURPOSE: Bridge Luigi orchestrator execution onto the OpenAI Agents SDK while
- *          emitting responses compatible with the existing agent runner contract.
- * SRP/DRY check: Pass - encapsulates SDK invocation logic without touching
- *                routing, storage orchestration, or REST fallback paths.
+ * Author: gpt-5-codex (building on ChatGPT-4.1)
+ * Date: 2025-11-06T04:10:30Z
+ * PURPOSE: Bridge ARC agent orchestrator execution onto OpenAI Agents SDK while emitting Luigi-compatible responses.
+ * SRP/DRY check: Pass - encapsulates SDK invocation logic without touching routing or storage orchestration.
  */
 
 import { Agent, run as runAgent } from '@openai/agents-core';
-import { LUIGI_STAGES } from '@shared/luigi-types';
+import { LUIGI_STAGES, type ArcExample } from '@shared/luigi-types';
 import type { LuigiMessage, LuigiRun } from '@shared/schema';
 import type { LuigiStageId, LuigiStageStatus } from '@shared/luigi-types';
 import { storage } from '../storage';
@@ -22,10 +20,19 @@ export interface LuigiSdkRunOptions {
   maxTurns?: number;
 }
 
+export interface LuigiArcContext {
+  taskId: string;
+  analysisBrief: string;
+  trainingExamples: ArcExample[];
+  evaluationExample?: ArcExample;
+  workspaceNotes?: string;
+}
+
 export interface LuigiSdkRunParams {
   run: LuigiRun;
   userReply?: string;
   options: LuigiSdkRunOptions;
+  arcContext?: LuigiArcContext;
 }
 
 type StageSnapshot = {
@@ -40,30 +47,31 @@ type StageSnapshotRecord = Partial<Record<LuigiStageId, StageSnapshot>>;
 const VALID_STAGE_STATUSES: readonly LuigiStageStatus[] = ['idle', 'in-progress', 'completed', 'blocked', 'failed'];
 const VALID_STAGE_STATUS_SET = new Set<LuigiStageStatus>(VALID_STAGE_STATUSES);
 
-const orchestratorInstructions = `You are the Luigi Master Orchestrator. Coordinate stage leads,
-aggregate validated information, and surface action items. Always respond in
-GitHub-flavoured Markdown with the following sections only:
+const orchestratorInstructions = `You are the ARC Orchestrator. Coordinate specialised agents to solve ARC puzzles by:
+- Extracting transformation hypotheses from training pairs.
+- Validating transformations across all examples and highlighting conflicts.
+- Generalising to evaluation grids with reasoning for each output.
+Always respond in GitHub-flavoured Markdown with the following sections only:
 
 ## Stage Progress
 - Bullet list summarising the current status for each relevant stage.
 
-## Key Risks
-- Bullet list of the most pressing risks or uncertainties.
+## Key Hypotheses
+- Bullet list describing active transformation hypotheses and their support.
 
 ## Required Inputs
-- Bullet list describing information or decisions needed from humans.
+- Bullet list of additional data or clarifications needed.
 
-## Recommended Actions
-- Bullet list of concrete next steps for the stage leads or stakeholders.
+## Proposed Outputs
+- Bullet list of predicted outputs (JSON arrays) with concise justification.
 
-When referencing stages, use their human-friendly names. Stay concise (<= 250
-words total) while maintaining clarity.`;
+Keep responses concise (<= 250 words) while preserving clarity.`;
 
 export async function runLuigiOrchestratorWithSdk(
   params: LuigiSdkRunParams,
 ): Promise<AgentRunResponse> {
-  const { run, userReply, options } = params;
-  const missionBrief = buildMissionBrief(run);
+  const { run, userReply, options, arcContext } = params;
+  const missionBrief = buildMissionBrief(run, arcContext);
   const stageSnapshots = coerceStageSnapshots(run);
   const stageSummary = buildStageSummary(stageSnapshots);
   const history = await fetchConversationHistory(run.id);
@@ -74,14 +82,14 @@ export async function runLuigiOrchestratorWithSdk(
     promptSections.push(conversationContext);
   }
   if (userReply) {
-    promptSections.push(`Latest stakeholder message:\n${userReply}`);
+    promptSections.push(`Latest human feedback:\n${userReply}`);
   }
   promptSections.push(
-    'Deliver the requested sections using Markdown and reference specific stages where helpful.',
+    'Deliver the requested sections using Markdown and include JSON arrays for any predicted outputs.'
   );
 
   const agent = new Agent({
-    name: 'Luigi Master Orchestrator',
+    name: 'ARC Master Orchestrator',
     instructions: orchestratorInstructions,
     model: options.model,
   });
@@ -96,20 +104,20 @@ export async function runLuigiOrchestratorWithSdk(
 
   return {
     status: 'running',
-    currentStageId: 'start-time-task',
+    currentStageId: 'ingest-arc-task',
     stageSnapshots: enrichedSnapshots,
     messages: [
       {
         role: 'orchestrator',
-        agentId: 'luigi-master-orchestrator',
+        agentId: 'arc-master-orchestrator',
         content: finalOutput,
       },
     ],
     artifacts: [
       {
-        stageId: 'start-time-task',
+        stageId: 'ingest-arc-task',
         type: 'markdown',
-        title: 'Luigi Orchestrator Briefing',
+        title: 'ARC Orchestrator Briefing',
         description: 'Markdown briefing generated via OpenAI Agents SDK.',
         data: { markdown: finalOutput },
       },
@@ -123,21 +131,51 @@ async function fetchConversationHistory(runId: string): Promise<LuigiMessage[]>
     const messages = await storage.getLuigiMessages(runId, HISTORY_LIMIT);
     return messages;
   } catch (error) {
-    throw new Error(`Failed to load Luigi conversation history for run ${runId}: ${String(error)}`);
+    throw new Error(`Failed to load ARC conversation history for run ${runId}: ${String(error)}`);
+  }
+}
+
+function parseExamples(raw?: string | null): ArcExample[] {
+  if (!raw) return [];
+  try {
+    const parsed = JSON.parse(raw) as unknown;
+    return Array.isArray(parsed) ? (parsed as ArcExample[]) : [];
+  } catch {
+    return [];
+  }
+}
+
+function parseExample(raw?: string | null): ArcExample | undefined {
+  if (!raw) return undefined;
+  try {
+    return JSON.parse(raw) as ArcExample;
+  } catch {
+    return undefined;
   }
 }
 
-function buildMissionBrief(run: LuigiRun): string {
+function buildMissionBrief(run: LuigiRun, context?: LuigiArcContext): string {
+  const taskId = context?.taskId ?? run.missionName;
+  const analysisBrief = context?.analysisBrief ?? run.objective;
+  const trainingExamples = context?.trainingExamples ?? parseExamples(run.constraints);
+  const evaluationExample = context?.evaluationExample ?? parseExample(run.successCriteria);
+  const workspaceNotes = context?.workspaceNotes ?? run.stakeholderNotes ?? undefined;
+
   const lines: string[] = [
-    `Mission Name: ${run.missionName}`,
-    `Objective: ${run.objective}`,
+    `ARC Task ID: ${taskId}`,
+    `Mission Brief: ${analysisBrief}`,
+    `Training Examples (JSON):\n${JSON.stringify(trainingExamples, null, 2)}`,
   ];
 
-  if (run.constraints) lines.push(`Constraints: ${run.constraints}`);
-  if (run.successCriteria) lines.push(`Success Criteria: ${run.successCriteria}`);
-  if (run.stakeholderNotes) lines.push(`Stakeholder Notes: ${run.stakeholderNotes}`);
+  if (evaluationExample) {
+    lines.push(`Evaluation Example (JSON):\n${JSON.stringify(evaluationExample, null, 2)}`);
+  }
 
-  return `Mission Brief:\n${lines.join('\n')}`;
+  if (workspaceNotes) {
+    lines.push(`Workspace Notes: ${workspaceNotes}`);
+  }
+
+  return `Mission Brief:\n${lines.join('\n\n')}`;
 }
 
 function coerceStageSnapshots(run: LuigiRun): StageSnapshotRecord {
@@ -201,60 +239,46 @@ function buildConversationContext(messages: LuigiMessage[]): string {
 
 function formatRole(role: string): string {
   switch (role) {
-    case 'stage-lead':
-      return 'Stage Lead';
     case 'orchestrator':
       return 'Orchestrator';
+    case 'stage-lead':
+      return 'Stage Lead';
     case 'agent':
       return 'Agent';
     case 'user':
-      return 'Stakeholder';
+      return 'User';
     default:
-      return role;
+      return 'System';
   }
 }
 
-function stringifyFinalOutput(finalOutput: unknown): string {
-  if (typeof finalOutput === 'string') {
-    return finalOutput.trim();
+function normalizeStageStatus(status: unknown): LuigiStageStatus {
+  if (typeof status !== 'string') {
+    return 'idle';
   }
 
-  return JSON.stringify(finalOutput, null, 2);
-}
+  if (VALID_STAGE_STATUS_SET.has(status as LuigiStageStatus)) {
+    return status as LuigiStageStatus;
+  }
 
-function markInitialStage(
-  stages: StageSnapshotRecord,
-  timestamp: string,
-): StageSnapshotRecord {
-  const updated: StageSnapshotRecord = { ...stages };
-  const existing = updated['start-time-task'] ?? { status: 'idle' };
-  updated['start-time-task'] = {
-    ...existing,
-    status: 'completed',
-    startedAt: existing.startedAt ?? timestamp,
-    completedAt: timestamp,
-  };
-  return updated;
+  return 'idle';
 }
 
-function normalizeStageStatus(value: unknown): LuigiStageStatus {
-  if (typeof value === 'string') {
-    if (VALID_STAGE_STATUS_SET.has(value as LuigiStageStatus)) {
-      return value as LuigiStageStatus;
-    }
-    if (value === 'complete') {
-      return 'completed';
-    }
-    if (value === 'in_progress') {
-      return 'in-progress';
-    }
-    if (value === 'blocking') {
-      return 'blocked';
-    }
-    if (value === 'error') {
-      return 'failed';
-    }
+function markInitialStage(stages: StageSnapshotRecord, timestamp: string): StageSnapshotRecord {
+  const clone: StageSnapshotRecord = { ...stages };
+  if (!clone['ingest-arc-task']) {
+    clone['ingest-arc-task'] = { status: 'in-progress', startedAt: timestamp };
   }
+  return clone;
+}
 
-  return 'idle';
+function stringifyFinalOutput(finalOutput: unknown): string {
+  if (typeof finalOutput === 'string') {
+    return finalOutput;
+  }
+  try {
+    return JSON.stringify(finalOutput, null, 2);
+  } catch (error) {
+    return `Unable to stringify orchestrator output: ${String(error)}`;
+  }
 }
diff --git a/server/routes/luigi.ts b/server/routes/luigi.ts
index d12765c..4b0e030 100644
--- a/server/routes/luigi.ts
+++ b/server/routes/luigi.ts
@@ -1,9 +1,8 @@
 /*
- * Author: Codex using GPT-5
- * Date: 2025-10-04T02:04:20Z
- * PURPOSE: Express router exposing Luigi agent workspace REST endpoints.
- * SRP/DRY check: Pass - routes only, delegates to executor and storage.
- * shadcn/ui: Pass - backend only.
+ * Author: gpt-5-codex
+ * Date: 2025-11-06T04:09:30Z
+ * PURPOSE: Express router exposing ARC agent workspace endpoints with ARC-specific validation.
+ * SRP/DRY check: Pass - routes only, delegates to executor and storage services.
  */
 
 import { Router } from 'express';
@@ -14,12 +13,18 @@ import { getLuigiConfig } from '../config.js';
 import type { LuigiRunParams } from '../luigi/executor';
 import { LUIGI_STAGES } from '@shared/luigi-types';
 
+const gridSchema = z.array(z.array(z.number().int().min(0).max(9)).min(1)).min(1);
+const arcExampleSchema = z.object({
+  input: gridSchema,
+  output: gridSchema.optional(),
+});
+
 const createRunSchema = z.object({
-  missionName: z.string().min(3),
-  objective: z.string().min(5),
-  constraints: z.string().optional(),
-  successCriteria: z.string().optional(),
-  stakeholderNotes: z.string().optional(),
+  taskId: z.string().min(3),
+  analysisBrief: z.string().min(10),
+  trainingExamples: z.array(arcExampleSchema).min(1),
+  evaluationExample: arcExampleSchema.optional(),
+  workspaceNotes: z.string().optional(),
 });
 
 const userReplySchema = z.object({
diff --git a/shared/luigi-types.ts b/shared/luigi-types.ts
index 3f1317f..be826c2 100644
--- a/shared/luigi-types.ts
+++ b/shared/luigi-types.ts
@@ -1,71 +1,18 @@
-/*
- * Author: Codex using GPT-5
- * Date: 2025-10-04T01:44:52Z
- * PURPOSE: Shared type definitions for Luigi workspace API contracts covering runs, stages, messages, and artifacts.
- * SRP/DRY check: Pass - centralizes Luigi-specific shared types to avoid duplication across client and server.
- * shadcn/ui: Pass - no UI usage in shared types.
+/*
+ * Author: gpt-5-codex
+ * Date: 2025-11-06T04:09:00Z
+ * PURPOSE: Shared ARC agent types for runs, stages, messages, and artifacts.
+ * SRP/DRY check: Pass - centralizes ARC agent contracts for reuse across client and server.
  */
 
 export const LUIGI_STAGES = [
-  { id: 'start-time-task', label: 'Start Time Task' },
-  { id: 'setup-task', label: 'Setup Task' },
-  { id: 'redline-gate-task', label: 'Redline Gate Task' },
-  { id: 'premise-attack-task', label: 'Premise Attack Task' },
-  { id: 'identify-purpose-task', label: 'Identify Purpose Task' },
-  { id: 'make-assumptions-task', label: 'Make Assumptions Task' },
-  { id: 'distill-assumptions-task', label: 'Distill Assumptions Task' },
-  { id: 'review-assumptions-task', label: 'Review Assumptions Task' },
-  { id: 'identify-risks-task', label: 'Identify Risks Task' },
-  { id: 'risk-matrix-task', label: 'Risk Matrix Task' },
-  { id: 'risk-mitigation-plan-task', label: 'Risk Mitigation Plan Task' },
-  { id: 'currency-strategy-task', label: 'Currency Strategy Task' },
-  { id: 'physical-locations-task', label: 'Physical Locations Task' },
-  { id: 'strategic-decisions-markdown-task', label: 'Strategic Decisions Markdown Task' },
-  { id: 'scenarios-markdown-task', label: 'Scenarios Markdown Task' },
-  { id: 'expert-finder-task', label: 'Expert Finder Task' },
-  { id: 'expert-criticism-task', label: 'Expert Criticism Task' },
-  { id: 'expert-orchestrator-task', label: 'Expert Orchestrator Task' },
-  { id: 'create-wbs-level-1', label: 'Create WBS Level 1' },
-  { id: 'create-wbs-level-2', label: 'Create WBS Level 2' },
-  { id: 'create-wbs-level-3', label: 'Create WBS Level 3' },
-  { id: 'identify-wbs-task-dependencies', label: 'Identify WBS Task Dependencies' },
-  { id: 'estimate-wbs-task-durations', label: 'Estimate WBS Task Durations' },
-  { id: 'wbs-populate', label: 'WBS Populate' },
-  { id: 'wbs-task-tooltip', label: 'WBS Task Tooltip' },
-  { id: 'project-schedule-populator', label: 'Project Schedule Populator' },
-  { id: 'project-schedule', label: 'Project Schedule' },
-  { id: 'export-gantt-dhtmlx', label: 'Export Gantt DHTMLX' },
-  { id: 'export-gantt-csv', label: 'Export Gantt CSV' },
-  { id: 'export-gantt-mermaid', label: 'Export Gantt Mermaid' },
-  { id: 'find-team-members', label: 'Find Team Members' },
-  { id: 'enrich-team-members-contract-type', label: 'Enrich Team Members Contract Type' },
-  { id: 'enrich-team-members-background', label: 'Enrich Team Members Background' },
-  { id: 'enrich-team-members-environment', label: 'Enrich Team Members Environment' },
-  { id: 'team-markdown-document-builder', label: 'Team Markdown Document Builder' },
-  { id: 'review-team', label: 'Review Team' },
-  { id: 'create-pitch', label: 'Create Pitch' },
-  { id: 'convert-pitch-to-markdown', label: 'Convert Pitch To Markdown' },
-  { id: 'executive-summary', label: 'Executive Summary' },
-  { id: 'review-plan', label: 'Review Plan' },
-  { id: 'report-generator', label: 'Report Generator' },
-  { id: 'governance-phase-1-audit', label: 'Governance Phase 1 Audit' },
-  { id: 'governance-phase-2-internal-bodies', label: 'Governance Phase 2 Internal Bodies' },
-  { id: 'governance-phase-3-implementation-plan', label: 'Governance Phase 3 Implementation Plan' },
-  { id: 'governance-phase-4-decision-matrix', label: 'Governance Phase 4 Decision Matrix' },
-  { id: 'governance-phase-5-monitoring', label: 'Governance Phase 5 Monitoring' },
-  { id: 'governance-phase-6-extra', label: 'Governance Phase 6 Extra' },
-  { id: 'consolidate-governance', label: 'Consolidate Governance' },
-  { id: 'data-collection', label: 'Data Collection' },
-  { id: 'obtain-output-files', label: 'Obtain Output Files' },
-  { id: 'pipeline-environment', label: 'Pipeline Environment' },
-  { id: 'llm-executor', label: 'LLM Executor' },
-  { id: 'wbs-json-exporter', label: 'WBS JSON Exporter' },
-  { id: 'wbs-dot-exporter', label: 'WBS DOT Exporter' },
-  { id: 'wbs-png-exporter', label: 'WBS PNG Exporter' },
-  { id: 'wbs-pdf-exporter', label: 'WBS PDF Exporter' },
-  { id: 'budget-estimation-task', label: 'Budget Estimation Task' },
-  { id: 'cashflow-projection-task', label: 'Cashflow Projection Task' },
-  { id: 'final-report-assembler', label: 'Final Report Assembler' }
+  { id: 'ingest-arc-task', label: 'Ingest ARC Task' },
+  { id: 'pattern-discovery', label: 'Pattern Discovery' },
+  { id: 'transformation-simulation', label: 'Transformation Simulation' },
+  { id: 'generalization-evaluation', label: 'Generalization Evaluation' },
+  { id: 'solution-synthesis', label: 'Solution Synthesis' },
+  { id: 'critique-review', label: 'Critique & Review' },
+  { id: 'deliverable-export', label: 'Deliverable Export' },
 ] as const;
 
 export type LuigiStageId = typeof LUIGI_STAGES[number]['id'];
@@ -101,12 +48,17 @@ export interface LuigiRunSummary {
   totalCostCents?: number;
 }
 
+export interface ArcExample {
+  input: number[][];
+  output?: number[][];
+}
+
 export interface CreateLuigiRunRequest {
-  missionName: string;
-  objective: string;
-  constraints?: string;
-  successCriteria?: string;
-  stakeholderNotes?: string;
+  taskId: string;
+  analysisBrief: string;
+  trainingExamples: ArcExample[];
+  evaluationExample?: ArcExample;
+  workspaceNotes?: string;
 }
 
 export interface CreateLuigiRunResponse {