diff --git a/src/lib/format.ts b/src/lib/format.ts
new file mode 100644
index 0000000..e232304
--- /dev/null
+++ b/src/lib/format.ts
@@ -0,0 +1,17 @@
+/**
+ * Shared formatting utilities for Mission Control.
+ *
+ * Centralizes formatting logic to avoid duplication across components.
+ */
+
+import type { FocusItemType } from "./types";
+
+/**
+ * Format an IID with the appropriate prefix for its type.
+ *
+ * MRs use ! prefix, issues use # prefix.
+ */
+export function formatIid(type: FocusItemType, iid: number): string {
+  if (type === "mr_review" || type === "mr_authored") return `!${iid}`;
+  return `#${iid}`;
+}
diff --git a/src/lib/tauri.ts b/src/lib/tauri.ts
new file mode 100644
index 0000000..963c4b7
--- /dev/null
+++ b/src/lib/tauri.ts
@@ -0,0 +1,29 @@
+/**
+ * Tauri IPC wrapper.
+ *
+ * Thin layer over @tauri-apps/api invoke that provides typed
+ * function signatures for each Rust command.
+ */
+
+import { invoke } from "@tauri-apps/api/core";
+import type { BridgeStatus, CaptureResult, LoreStatus, SyncResult } from "./types";
+
+export async function getLoreStatus(): Promise<LoreStatus> {
+  return invoke<LoreStatus>("get_lore_status");
+}
+
+export async function getBridgeStatus(): Promise<BridgeStatus> {
+  return invoke<BridgeStatus>("get_bridge_status");
+}
+
+export async function syncNow(): Promise<SyncResult> {
+  return invoke<SyncResult>("sync_now");
+}
+
+export async function reconcile(): Promise<SyncResult> {
+  return invoke<SyncResult>("reconcile");
+}
+
+export async function quickCapture(title: string): Promise<CaptureResult> {
+  return invoke<CaptureResult>("quick_capture", { title });
+}
diff --git a/src/lib/transform.ts b/src/lib/transform.ts
new file mode 100644
index 0000000..28ca60a
--- /dev/null
+++ b/src/lib/transform.ts
@@ -0,0 +1,87 @@
+/**
+ * Transform lore backend data into FocusItem[] for the UI.
+ *
+ * Converts LoreStatus (issues, MRs) into a flat list of FocusItems
+ * sorted by priority: reviews first (blocking others), then issues,
+ * then authored MRs.
+ */
+
+import type { FocusItem } from "./types";
+
+/** Shape of lore issue from the backend */
+interface LoreIssue {
+  iid: number;
+  title: string;
+  project: string;
+  web_url: string;
+  updated_at_iso?: string | null;
+  attention_state?: string | null;
+}
+
+/** Shape of lore MR from the backend */
+interface LoreMr {
+  iid: number;
+  title: string;
+  project: string;
+  web_url: string;
+  updated_at_iso?: string | null;
+  attention_state?: string | null;
+  author_username?: string | null;
+}
+
+interface LoreMeData {
+  open_issues: LoreIssue[];
+  open_mrs_authored: LoreMr[];
+  reviewing_mrs: LoreMr[];
+}
+
+export function transformLoreData(data: LoreMeData): FocusItem[] {
+  const items: FocusItem[] = [];
+
+  // Reviews first (you're blocking someone)
+  for (const mr of data.reviewing_mrs) {
+    items.push({
+      id: `mr_review:${mr.project}:${mr.iid}`,
+      title: mr.title,
+      type: "mr_review",
+      project: mr.project,
+      url: mr.web_url,
+      iid: mr.iid,
+      updatedAt: mr.updated_at_iso ?? null,
+      contextQuote: null,
+      requestedBy: mr.author_username ?? null,
+    });
+  }
+
+  // Assigned issues
+  for (const issue of data.open_issues) {
+    items.push({
+      id: `issue:${issue.project}:${issue.iid}`,
+      title: issue.title,
+      type: "issue",
+      project: issue.project,
+      url: issue.web_url,
+      iid: issue.iid,
+      updatedAt: issue.updated_at_iso ?? null,
+      contextQuote: null,
+      requestedBy: null,
+    });
+  }
+
+  // Authored MRs last (your own work, less urgent)
+  for (const mr of data.open_mrs_authored) {
+    items.push({
+      id: `mr_authored:${mr.project}:${mr.iid}`,
+      title: mr.title,
+      type: "mr_authored",
+      project: mr.project,
+      url: mr.web_url,
+      iid: mr.iid,
+      updatedAt: mr.updated_at_iso ?? null,
+      contextQuote: null,
+      requestedBy: null,
+    });
+  }
+
+  return items;
+}
diff --git a/src/lib/types.ts b/src/lib/types.ts
new file mode 100644
index 0000000..ec2072a
--- /dev/null
+++ b/src/lib/types.ts
@@ -0,0 +1,132 @@
+/**
+ * TypeScript types mirroring the Rust backend data structures.
+ *
+ * These are used by the IPC layer and components to maintain
+ * type safety across the Tauri boundary.
+ */
+
+// -- Backend response types (match Rust structs in commands/mod.rs) --
+
+export interface LoreStatus {
+  last_sync: string | null;
+  is_healthy: boolean;
+  message: string;
+  summary: LoreSummaryStatus | null;
+}
+
+export interface LoreSummaryStatus {
+  open_issues: number;
+  authored_mrs: number;
+  reviewing_mrs: number;
+}
+
+export interface BridgeStatus {
+  mapping_count: number;
+  pending_count: number;
+  suspect_count: number;
+  last_sync: string | null;
+  last_reconciliation: string | null;
+}
+
+export interface SyncResult {
+  created: number;
+  closed: number;
+  skipped: number;
+  /** Number of suspect_orphan flags cleared (item reappeared) */
+  healed: number;
+  /** Error messages from non-fatal errors during sync */
+  errors: string[];
+}
+
+// -- Structured error types (match Rust error.rs) --
+
+/** Error codes for programmatic handling */
+export type McErrorCode =
+  | "LORE_UNAVAILABLE"
+  | "LORE_UNHEALTHY"
+  | "LORE_FETCH_FAILED"
+  | "BRIDGE_LOCKED"
+  | "BRIDGE_MAP_CORRUPTED"
+  | "BRIDGE_SYNC_FAILED"
+  | "BEADS_UNAVAILABLE"
+  | "BEADS_CREATE_FAILED"
+  | "BEADS_CLOSE_FAILED"
+  | "IO_ERROR"
+  | "INTERNAL_ERROR";
+
+/** Structured error from Tauri IPC commands */
+export interface McError {
+  code: McErrorCode;
+  message: string;
+  recoverable: boolean;
+}
+
+/** Type guard to check if an error is a structured McError */
+export function isMcError(err: unknown): err is McError {
+  return (
+    typeof err === "object" &&
+    err !== null &&
+    "code" in err &&
+    "message" in err &&
+    "recoverable" in err
+  );
+}
+
+/** Result from the quick_capture command */
+export interface CaptureResult {
+  bead_id: string;
+}
+
+// -- Frontend-only types --
+
+/** The type of work item surfaced in the Focus View */
+export type FocusItemType = "mr_review" | "issue" | "mr_authored" | "manual";
+
+/** A single work item that can be THE ONE THING */
+export interface FocusItem {
+  /** Unique key matching bridge mapping (e.g., "mr_review:g/p:847") */
+  id: string;
+  /** Human-readable title */
+  title: string;
+  /** Type badge to display */
+  type: FocusItemType;
+  /** Project path (e.g., "platform/core") */
+  project: string;
+  /** URL to open in browser (GitLab link) */
+  url: string;
+  /** Entity IID (e.g., MR !847, Issue #42) */
+  iid: number;
+  /** ISO timestamp of last update */
+  updatedAt: string | null;
+  /** Optional context quote (e.g., reviewer comment) */
+  contextQuote: string | null;
+  /** Who is requesting attention */
+  requestedBy: string | null;
+}
+
+/** Action the user takes on a focused item */
+export type FocusAction = "start" | "defer_1h" | "defer_tomorrow" | "skip";
+
+/** An entry in the decision log */
+export interface DecisionEntry {
+  timestamp: string;
+  action: FocusAction;
+  itemId: string;
+  reason: string | null;
+}
+
+/** Staleness level derived from item age */
+export type Staleness = "fresh" | "normal" | "amber" | "urgent";
+
+/** Compute staleness from an ISO timestamp */
+export function computeStaleness(updatedAt: string | null): Staleness {
+  if (!updatedAt) return "normal";
+
+  const ageMs = Date.now() - new Date(updatedAt).getTime();
+  const ageDays = ageMs / (1000 * 60 * 60 * 24);
+
+  if (ageDays < 1) return "fresh";
+  if (ageDays < 3) return "normal";
+  if (ageDays < 7) return "amber";
+  return "urgent";
+}