diff --git a/src/tools/__tests__/sdk-guides.test.ts b/src/tools/__tests__/sdk-guides.test.ts
new file mode 100644
index 0000000..939533c
--- /dev/null
+++ b/src/tools/__tests__/sdk-guides.test.ts
@@ -0,0 +1,84 @@
+import { describe, expect, it } from "vitest";
+import { Client } from "@modelcontextprotocol/sdk/client/index.js";
+import { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
+import { InMemoryTransport } from "@modelcontextprotocol/sdk/inMemory.js";
+import { register as registerLobby } from "../createLobby.js";
+import { register as registerWorkshop } from "../uploadWorkshopItem.js";
+
+async function callGuide(name: string, args: Record<string, unknown>) {
+  const server = new McpServer({ name: "sdk-guide-test", version: "1.0.0" });
+  registerLobby(server);
+  registerWorkshop(server);
+  const client = new Client({ name: "sdk-guide-client", version: "1.0.0" });
+  const [clientTransport, serverTransport] = InMemoryTransport.createLinkedPair();
+  await server.connect(serverTransport);
+  await client.connect(clientTransport);
+  try {
+    const result = await client.callTool({ name, arguments: args });
+    expect(result.isError).not.toBe(true);
+    const content = result.content as Array<{ type: string; text: string }>;
+    return JSON.parse(content[0].text) as Record<string, unknown>;
+  } finally {
+    await client.close();
+    await server.close();
+  }
+}
+
+describe("SDK guides", () => {
+  it("escapes Workshop text, Windows paths and tags in every generated language", async () => {
+    const title = 'A "quoted" title\nnext line';
+    const description = 'Line one\r\nLine two\twith "quotes"';
+    const content_path = "C:\\mods\\new";
+    const preview_path = 'C:\\images\\my "preview".png';
+    const tag = 'tag"\\value';
+    const guide = await callGuide("steam_uploadWorkshopItem", {
+      appid: 480, title, description, content_path, preview_path, tags: [tag],
+    });
+
+    expect(guide.title).toBe(title);
+    expect(guide.description).toBe(description);
+    expect(guide.content_path).toBe(content_path);
+    expect(guide.preview_path).toBe(preview_path);
+    expect(guide.tags).toEqual([tag]);
+    for (const language of ["cpp", "gdscript"]) {
+      const code = guide[language] as string;
+      expect(code).toContain('A \\"quoted\\" title');
+      expect(code).toContain('C:\\\\mods\\\\new');
+      expect(code).toContain('C:\\\\images\\\\my \\"preview\\".png');
+      expect(code).not.toContain(title);
+    }
+    expect(guide.cpp).toContain('tag\\"\\\\value');
+    expect(guide.cpp).toContain('Line one\\015\\012Line two\\011with \\"quotes\\"');
+    expect(guide.gdscript).toContain('title\\nnext line');
+  });
+
+  it("escapes lobby metadata keys and values without changing metadata", async () => {
+    const metadata = { 'map"\\name': 'C:\\maps\\new\n"arena"' };
+    const guide = await callGuide("steam_createLobby", {
+      type: "public", max_members: 4, metadata,
+    });
+
+    expect(guide.metadata).toEqual(metadata);
+    for (const language of ["cpp", "csharp", "gdscript"]) {
+      const code = guide[language] as string;
+      expect(code).toContain('"map\\"\\\\name"');
+      expect(code).toContain('C:\\\\maps\\\\new');
+      expect(code).toContain('\\"arena\\"');
+      expect(code).not.toContain(metadata['map"\\name']);
+    }
+    expect(guide.cpp).toContain('new\\012\\"arena\\"');
+    expect(guide.csharp).toContain('new\\n\\"arena\\"');
+    expect(guide.gdscript).toContain('new\\n\\"arena\\"');
+  });
+
+  it("retains ordinary defaults and empty strings in guides", async () => {
+    const workshop = await callGuide("steam_uploadWorkshopItem", { appid: 480, title: "Example" });
+    expect(workshop.cpp).toContain('SetItemTitle(handle, "Example")');
+    expect(workshop.cpp).toContain('SetItemContent(handle, "/path/to/content")');
+    expect(workshop.gdscript).toContain('"res://workshop_content"');
+    const lobby = await callGuide("steam_createLobby", {
+      type: "private", max_members: 2, metadata: { empty: "" },
+    });
+    expect(lobby.csharp).toContain('SetLobbyData(lobbyId, "empty", "")');
+  });
+});
diff --git a/src/tools/createLobby.ts b/src/tools/createLobby.ts
index 36ed08f..052228c 100644
--- a/src/tools/createLobby.ts
+++ b/src/tools/createLobby.ts
@@ -1,5 +1,6 @@
 import { z } from "zod";
 import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
+import { escapeStringLiteral } from "../utils/string-literal.js";
 import { LOCAL_ONLY } from "../utils/annotations.js";
 
 const inputSchema = {
@@ -43,19 +44,19 @@ export function register(server: McpServer): void {
       const metaCpp = metaEntries
         .map(
           ([k, v]) =>
-            `  SteamMatchmaking()->SetLobbyData(lobbyId, "${k}", "${v}");`,
+            `  SteamMatchmaking()->SetLobbyData(lobbyId, ${escapeStringLiteral(k, "cpp")}, ${escapeStringLiteral(v, "cpp")});`,
         )
         .join("\n");
       const metaCs = metaEntries
         .map(
           ([k, v]) =>
-            `  SteamMatchmaking.SetLobbyData(lobbyId, "${k}", "${v}");`,
+            `  SteamMatchmaking.SetLobbyData(lobbyId, ${escapeStringLiteral(k, "csharp")}, ${escapeStringLiteral(v, "csharp")});`,
         )
         .join("\n");
       const metaGd = metaEntries
         .map(
           ([k, v]) =>
-            `  Steam.setLobbyData(lobby_id, "${k}", "${v}")`,
+            `  Steam.setLobbyData(lobby_id, ${escapeStringLiteral(k, "gdscript")}, ${escapeStringLiteral(v, "gdscript")})`,
         )
         .join("\n");
 
diff --git a/src/tools/uploadWorkshopItem.ts b/src/tools/uploadWorkshopItem.ts
index 4a06f1f..c5b0535 100644
--- a/src/tools/uploadWorkshopItem.ts
+++ b/src/tools/uploadWorkshopItem.ts
@@ -1,5 +1,6 @@
 import { z } from "zod";
 import type { McpServer } from "@modelcontextprotocol/sdk/server/mcp.js";
+import { escapeStringLiteral } from "../utils/string-literal.js";
 import { LOCAL_ONLY } from "../utils/annotations.js";
 
 const inputSchema = {
@@ -80,17 +81,17 @@ export function register(server: McpServer): void {
           "  PublishedFileId_t fileId = pResult->m_nPublishedFileId;",
           "",
           `  UGCUpdateHandle_t handle = SteamUGC()->StartItemUpdate(${appid}, fileId);`,
-          `  SteamUGC()->SetItemTitle(handle, "${title}");`,
+          `  SteamUGC()->SetItemTitle(handle, ${escapeStringLiteral(title, "cpp")});`,
           description
-            ? `  SteamUGC()->SetItemDescription(handle, "${description}");`
+            ? `  SteamUGC()->SetItemDescription(handle, ${escapeStringLiteral(description, "cpp")});`
             : "  // SteamUGC()->SetItemDescription(handle, \"...\");",
-          `  SteamUGC()->SetItemContent(handle, "${content_path ?? "/path/to/content"}");`,
-          `  SteamUGC()->SetItemPreview(handle, "${preview_path ?? "/path/to/preview.jpg"}");`,
+          `  SteamUGC()->SetItemContent(handle, ${escapeStringLiteral(content_path ?? "/path/to/content", "cpp")});`,
+          `  SteamUGC()->SetItemPreview(handle, ${escapeStringLiteral(preview_path ?? "/path/to/preview.jpg", "cpp")});`,
           `  SteamUGC()->SetItemVisibility(handle, ${visEnum});`,
           ...(tags && tags.length > 0
             ? [
                 "  SteamParamStringArray_t tagArray;",
-                `  const char* tagStrings[] = { ${tags.map((t) => `"${t}"`).join(", ")} };`,
+                `  const char* tagStrings[] = { ${tags.map((t) => escapeStringLiteral(t, "cpp")).join(", ")} };`,
                 `  tagArray.m_ppStrings = tagStrings;`,
                 `  tagArray.m_nNumStrings = ${tags.length};`,
                 "  SteamUGC()->SetItemTags(handle, &tagArray);",
@@ -114,9 +115,9 @@ export function register(server: McpServer): void {
           '    print("Failed to create item")',
           "    return",
           "  var handle = Steam.startItemUpdate(app_id, file_id)",
-          `  Steam.setItemTitle(handle, "${title}")`,
-          `  Steam.setItemContent(handle, "${content_path ?? "res://workshop_content"}")`,
-          `  Steam.setItemPreview(handle, "${preview_path ?? "res://preview.png"}")`,
+          `  Steam.setItemTitle(handle, ${escapeStringLiteral(title, "gdscript")})`,
+          `  Steam.setItemContent(handle, ${escapeStringLiteral(content_path ?? "res://workshop_content", "gdscript")})`,
+          `  Steam.setItemPreview(handle, ${escapeStringLiteral(preview_path ?? "res://preview.png", "gdscript")})`,
           `  Steam.setItemVisibility(handle, Steam.REMOTE_STORAGE_PUBLISHED_FILE_VISIBILITY_${vis.toUpperCase()})`,
           '  Steam.submitItemUpdate(handle, "Initial upload")',
         ].join("\n"),
diff --git a/src/utils/string-literal.ts b/src/utils/string-literal.ts
new file mode 100644
index 0000000..2ee6120
--- /dev/null
+++ b/src/utils/string-literal.ts
@@ -0,0 +1,19 @@
+type GuideLanguage = "cpp" | "csharp" | "gdscript";
+
+/** Return a quoted source literal, not a JSON-encoded code fragment. */
+export function escapeStringLiteral(value: string, language: GuideLanguage): string {
+  if (language !== "cpp") {
+    return JSON.stringify(value)
+      .replace(/\u2028/g, "\\u2028")
+      .replace(/\u2029/g, "\\u2029");
+  }
+
+  // Fixed-width octal preserves UTF-8 bytes without consuming a following digit.
+  const escaped = Array.from(Buffer.from(value, "utf8"), (byte) => {
+    if (byte === 0x22) return '\\"';
+    if (byte === 0x5c) return "\\\\";
+    if (byte >= 0x20 && byte <= 0x7e) return String.fromCharCode(byte);
+    return `\\${byte.toString(8).padStart(3, "0")}`;
+  }).join("");
+  return `"${escaped}"`;
+}