Phase 1: types, zod runtime validation, structured errors, auth restore bugfix

scripts/sync-version.cjs

@@ -49,11 +49,10 @@ if (fs.existsSync(marketplacePath)) {
 const skillPaths = [
     "skills/interactive-leetcode-mcp/SKILL.md",
     ".claude/skills/using-interactive-leetcode-mcp/SKILL.md",
-    "clawhub-skill/interactive-leetcode-mcp/SKILL.md",
+    "clawhub-skill/interactive-leetcode-mcp/SKILL.md"
 ];
 
-const versionPattern =
-    /@sperekrestova\/interactive-leetcode-mcp@[\w.-]+/g;
+const versionPattern = /@sperekrestova\/interactive-leetcode-mcp@[\w.-]+/g;
 const versionReplacement = `@sperekrestova/interactive-leetcode-mcp@${version}`;
 
 for (const rel of skillPaths) {

src/auth/auth-flow.ts

@@ -0,0 +1,84 @@
+/**
+ * Authentication helpers that bridge the on-disk credentials store and the
+ * in-memory `LeetcodeServiceInterface`.
+ *
+ * Closes the silent-logout-on-restart gap where saved credentials existed in
+ * `~/.leetcode-mcp/credentials.json` but the running server never re-hydrated
+ * them, so every authenticated tool failed with "Authentication required" until
+ * the user pasted their cookies again.
+ */
+import { LeetcodeServiceInterface } from "../leetcode/leetcode-service-interface.js";
+import { CredentialsStorage } from "../types/credentials.js";
+import { credentialsStorage as defaultStorage } from "../utils/credentials.js";
+import logger from "../utils/logger.js";
+
+/** Outcome of an `restoreCredentials` call — useful in tests and logs. */
+export type RestoreOutcome =
+    | { status: "no_credentials" }
+    | { status: "invalid"; reason: "load_failed" | "expired" }
+    | { status: "restored"; username: string };
+
+/**
+ * Loads saved credentials from disk, validates them against LeetCode, and
+ * pushes them into the running service if they're still good.
+ *
+ * Safe to call at server startup; never throws — failures are logged and the
+ * outcome is returned for callers that want to react.
+ */
+export async function restoreCredentials(
+    service: LeetcodeServiceInterface,
+    storage: CredentialsStorage = defaultStorage
+): Promise<RestoreOutcome> {
+    if (!(await storage.exists())) {
+        return { status: "no_credentials" };
+    }
+
+    const credentials = await storage.load();
+    if (!credentials) {
+        logger.warn(
+            "Saved credentials file exists but could not be parsed; ignoring."
+        );
+        return { status: "invalid", reason: "load_failed" };
+    }
+
+    const username = await applyValidatedCredentials(
+        service,
+        credentials.csrftoken,
+        credentials.LEETCODE_SESSION
+    );
+
+    if (!username) {
+        logger.info(
+            "Saved credentials are no longer valid; user will need to re-authenticate."
+        );
+        return { status: "invalid", reason: "expired" };
+    }
+
+    logger.info(
+        "Restored LeetCode session for %s from saved credentials.",
+        username
+    );
+    return { status: "restored", username };
+}
+
+/**
+ * Validates `csrf` / `session` against LeetCode and, on success, pushes them
+ * into the running service so the very next authenticated tool call works
+ * without forcing a server restart.
+ *
+ * Returns the validated username, or `null` if LeetCode rejected the cookies.
+ * Trusts the `validateCredentials` interface contract (`Promise<string | null>`)
+ * and does not catch — any exception thrown by the service propagates.
+ */
+export async function applyValidatedCredentials(
+    service: LeetcodeServiceInterface,
+    csrf: string,
+    session: string
+): Promise<string | null> {
+    const username = await service.validateCredentials(csrf, session);
+    if (!username) {
+        return null;
+    }
+    service.updateCredentials(csrf, session);
+    return username;
+}

src/index.ts

@@ -6,6 +6,7 @@ import minimist from "minimist";
 import { readFileSync } from "node:fs";
 import { dirname, join } from "node:path";
 import { fileURLToPath } from "node:url";
+import { restoreCredentials } from "./auth/auth-flow.js";
 import { LeetCodeGlobalService } from "./leetcode/leetcode-global-service.js";
 import { LeetcodeServiceInterface } from "./leetcode/leetcode-service-interface.js";
 import { registerAuthPrompts } from "./mcp/prompts/auth-prompts.js";
@@ -121,6 +122,11 @@ async function main() {
         credential
     );
 
+    // Re-hydrate saved credentials from disk so authenticated tools work
+    // immediately after a server restart without forcing the user to paste
+    // their cookies again.
+    await restoreCredentials(leetcodeService);
+
     // Register MCP prompts for learning mode and workspace guidance
     registerLearningPrompts(server, leetcodeService);