diff --git a/src/shared/migration/agent-names.ts b/src/shared/migration/agent-names.ts
new file mode 100644
index 00000000..3321b0b8
--- /dev/null
+++ b/src/shared/migration/agent-names.ts
@@ -0,0 +1,70 @@
+export const AGENT_NAME_MAP: Record<string, string> = {
+  // Sisyphus variants → "sisyphus"
+  omo: "sisyphus",
+  OmO: "sisyphus",
+  Sisyphus: "sisyphus",
+  sisyphus: "sisyphus",
+
+  // Prometheus variants → "prometheus"
+  "OmO-Plan": "prometheus",
+  "omo-plan": "prometheus",
+  "Planner-Sisyphus": "prometheus",
+  "planner-sisyphus": "prometheus",
+  "Prometheus (Planner)": "prometheus",
+  prometheus: "prometheus",
+
+  // Atlas variants → "atlas"
+  "orchestrator-sisyphus": "atlas",
+  Atlas: "atlas",
+  atlas: "atlas",
+
+  // Metis variants → "metis"
+  "plan-consultant": "metis",
+  "Metis (Plan Consultant)": "metis",
+  metis: "metis",
+
+  // Momus variants → "momus"
+  "Momus (Plan Reviewer)": "momus",
+  momus: "momus",
+
+  // Sisyphus-Junior → "sisyphus-junior"
+  "Sisyphus-Junior": "sisyphus-junior",
+  "sisyphus-junior": "sisyphus-junior",
+
+  // Already lowercase - passthrough
+  build: "build",
+  oracle: "oracle",
+  librarian: "librarian",
+  explore: "explore",
+  "multimodal-looker": "multimodal-looker",
+}
+
+export const BUILTIN_AGENT_NAMES = new Set([
+  "sisyphus", // was "Sisyphus"
+  "oracle",
+  "librarian",
+  "explore",
+  "multimodal-looker",
+  "metis", // was "Metis (Plan Consultant)"
+  "momus", // was "Momus (Plan Reviewer)"
+  "prometheus", // was "Prometheus (Planner)"
+  "atlas", // was "Atlas"
+  "build",
+])
+
+export function migrateAgentNames(
+  agents: Record<string, unknown>
+): { migrated: Record<string, unknown>; changed: boolean } {
+  const migrated: Record<string, unknown> = {}
+  let changed = false
+
+  for (const [key, value] of Object.entries(agents)) {
+    const newKey = AGENT_NAME_MAP[key.toLowerCase()] ?? AGENT_NAME_MAP[key] ?? key
+    if (newKey !== key) {
+      changed = true
+    }
+    migrated[newKey] = value
+  }
+
+  return { migrated, changed }
+}
diff --git a/src/shared/migration/hook-names.ts b/src/shared/migration/hook-names.ts
new file mode 100644
index 00000000..35920272
--- /dev/null
+++ b/src/shared/migration/hook-names.ts
@@ -0,0 +1,36 @@
+// Migration map: old hook names → new hook names (for backward compatibility)
+// null means the hook was removed and should be filtered out from disabled_hooks
+export const HOOK_NAME_MAP: Record<string, string | null> = {
+  // Legacy names (backward compatibility)
+  "anthropic-auto-compact": "anthropic-context-window-limit-recovery",
+  "sisyphus-orchestrator": "atlas",
+
+  // Removed hooks (v3.0.0) - will be filtered out and user warned
+  "empty-message-sanitizer": null,
+}
+
+export function migrateHookNames(
+  hooks: string[]
+): { migrated: string[]; changed: boolean; removed: string[] } {
+  const migrated: string[] = []
+  const removed: string[] = []
+  let changed = false
+
+  for (const hook of hooks) {
+    const mapping = HOOK_NAME_MAP[hook]
+
+    if (mapping === null) {
+      removed.push(hook)
+      changed = true
+      continue
+    }
+
+    const newHook = mapping ?? hook
+    if (newHook !== hook) {
+      changed = true
+    }
+    migrated.push(newHook)
+  }
+
+  return { migrated, changed, removed }
+}