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diff --git a/src/features/mcp/logic/view-model.ts b/src/features/mcp/logic/view-model.ts
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+++ b/src/features/mcp/logic/view-model.ts
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+import type { McpServerInfo, McpServerState } from "@dispatch/transport-contract";
+
+/**
+ * Pure core for the mcp feature — zero DOM, zero effects, zero Svelte.
+ *
+ * The mcp feature exposes the live status of the MCP (Model Context Protocol)
+ * servers configured for a conversation's working directory, fetched from
+ * `GET /conversations/:id/mcp`. This module holds the pure logic: the mapping
+ * of a backend `McpServerState` to a display badge + label, and a one-line
+ * server summary. The effect (the HTTP get MCP status) is INJECTED via the
+ * `LoadMcpStatus` port below; the composition root implements it.
+ */
+
+// ── Injected port (consumer-defines-port; the composition root adapts the
+//    store's HTTP call to this shape). ──────────────────────────────────────────
+
+/** Outcome of `GET /conversations/:id/mcp`; `null` when no real conversation is focused. */
+export type McpStatusResult =
+  | { readonly ok: true; readonly cwd: string | null; readonly servers: readonly McpServerInfo[] }
+  | { readonly ok: false; readonly error: string };
+
+export type LoadMcpStatus = () => Promise<McpStatusResult | null>;
+
+// ── MCP server status → display view ───────────────────────────────────────────
+
+export type Badge = "success" | "warning" | "error" | "neutral";
+
+export interface McpServerView {
+  readonly id: string;
+  readonly state: McpServerState;
+  readonly statusLabel: string;
+  readonly badge: Badge;
+  /** True while the state is transient (show a spinner). */
+  readonly busy: boolean;
+  /** The error reason when `state === "error"`, else null. */
+  readonly error: string | null;
+  /** Number of tools discovered from this server. */
+  readonly toolCount: number;
+  /** Which config source the server was resolved from, else null. */
+  readonly configSource: string | null;
+}
+
+/**
+ * Map a server's state to a display label + badge severity + busy flag. Mirrors
+ * the LSP status visual treatment: `connected` → success, `connecting` (the
+ * transient state, analogous to LSP's `starting`) → warning + spinner, `error`
+ * → error, and `disconnected` (a stable idle state) → neutral.
+ */
+export function viewMcpServer(server: McpServerInfo): McpServerView {
+  let statusLabel: string;
+  let badge: Badge;
+  let busy = false;
+  switch (server.state) {
+    case "connected":
+      statusLabel = "Connected";
+      badge = "success";
+      break;
+    case "connecting":
+      statusLabel = "Connecting…";
+      badge = "warning";
+      busy = true;
+      break;
+    case "disconnected":
+      statusLabel = "Disconnected";
+      badge = "neutral";
+      break;
+    case "error":
+      statusLabel = "Error";
+      badge = "error";
+      break;
+  }
+  return {
+    id: server.id,
+    state: server.state,
+    statusLabel,
+    badge,
+    busy,
+    error: server.state === "error" ? (server.error ?? "Failed to connect") : null,
+    toolCount: server.toolCount,
+    configSource: server.configSource ?? null,
+  };
+}
+
+export function viewMcpServers(servers: readonly McpServerInfo[]): readonly McpServerView[] {
+  return servers.map(viewMcpServer);
+}
+
+/**
+ * A short one-line summary, e.g. "2 connected" / "1 connected, 1 connecting,
+ * 1 error". Only non-zero buckets are listed.
+ */
+export function summarizeMcpServers(servers: readonly McpServerInfo[]): string {
+  if (servers.length === 0) return "No MCP servers";
+  let connected = 0;
+  let connecting = 0;
+  let disconnected = 0;
+  let errored = 0;
+  for (const s of servers) {
+    if (s.state === "connected") connected++;
+    else if (s.state === "error") errored++;
+    else if (s.state === "connecting") connecting++;
+    else disconnected++;
+  }
+  const parts: string[] = [];
+  if (connected > 0) parts.push(`${connected} connected`);
+  if (connecting > 0) parts.push(`${connecting} connecting`);
+  if (disconnected > 0) parts.push(`${disconnected} disconnected`);
+  if (errored > 0) parts.push(`${errored} error${errored === 1 ? "" : "s"}`);
+  return parts.join(", ");
+}