diff --git a/bun.lock b/bun.lock
index 5042c56..10c12c2 100644
--- a/bun.lock
+++ b/bun.lock
@@ -48,6 +48,7 @@
         "unist-util-visit": "^5.1.0",
         "vite": "^8.0.0",
         "yaml": "^2.8.2",
+        "zod": "^4.3.6",
       },
       "devDependencies": {
         "@biomejs/biome": "^2.3.13",
diff --git a/examples/basic/chronicle.yaml b/examples/basic/chronicle.yaml
index 8c152a6..a14bf5d 100644
--- a/examples/basic/chronicle.yaml
+++ b/examples/basic/chronicle.yaml
@@ -1,7 +1,7 @@
 title: My Documentation
 description: Documentation powered by Chronicle
 url: https://docs.example.com
-contentDir: .
+content: .
 theme:
   name: default
 search:
diff --git a/packages/chronicle/package.json b/packages/chronicle/package.json
index a23682e..cb01e78 100644
--- a/packages/chronicle/package.json
+++ b/packages/chronicle/package.json
@@ -57,15 +57,16 @@
     "react-dom": "^19.0.0",
     "react-router": "^7.13.1",
     "remark-directive": "^4.0.0",
-    "remark-parse": "^11.0.0",
     "remark-frontmatter": "^5.0.0",
     "remark-gfm": "^4.0.1",
     "remark-mdx-frontmatter": "^5.2.0",
+    "remark-parse": "^11.0.0",
     "satori": "^0.25.0",
     "slugify": "^1.6.6",
     "unified": "^11.0.5",
     "unist-util-visit": "^5.1.0",
     "vite": "^8.0.0",
-    "yaml": "^2.8.2"
+    "yaml": "^2.8.2",
+    "zod": "^4.3.6"
   }
 }
\ No newline at end of file
diff --git a/packages/chronicle/src/cli/commands/build.ts b/packages/chronicle/src/cli/commands/build.ts
index becb1a5..02bf45e 100644
--- a/packages/chronicle/src/cli/commands/build.ts
+++ b/packages/chronicle/src/cli/commands/build.ts
@@ -1,6 +1,6 @@
 import chalk from 'chalk';
 import { Command } from 'commander';
-import { resolveConfigPath, resolveContentDir } from '@/cli/utils/config';
+import { loadCLIConfig } from '@/cli/utils/config';
 import { PACKAGE_ROOT } from '@/cli/utils/resolve';
 import { linkContent } from '@/cli/utils/scaffold';
 
@@ -13,8 +13,10 @@ export const buildCommand = new Command('build')
     'Deploy preset (vercel, cloudflare, node-server)'
   )
   .action(async options => {
-    const contentDir = resolveContentDir(options.content);
-    const configPath = resolveConfigPath(options.config);
+    const { contentDir, configPath, preset } = await loadCLIConfig(options.config, {
+      content: options.content,
+      preset: options.preset,
+    });
     await linkContent(contentDir);
 
     console.log(chalk.cyan('Building for production...'));
@@ -27,7 +29,7 @@ export const buildCommand = new Command('build')
       projectRoot: process.cwd(),
       contentDir,
       configPath,
-      preset: options.preset
+      preset
     });
 
     const builder = await createBuilder({ ...config, builder: {} });
diff --git a/packages/chronicle/src/cli/commands/dev.ts b/packages/chronicle/src/cli/commands/dev.ts
index 35c6a1a..3d73b6d 100644
--- a/packages/chronicle/src/cli/commands/dev.ts
+++ b/packages/chronicle/src/cli/commands/dev.ts
@@ -1,8 +1,6 @@
-import fs from 'node:fs';
-import path from 'node:path';
 import chalk from 'chalk';
 import { Command } from 'commander';
-import { resolveConfigPath, resolveContentDir } from '@/cli/utils/config';
+import { loadCLIConfig } from '@/cli/utils/config';
 import { PACKAGE_ROOT } from '@/cli/utils/resolve';
 import { linkContent } from '@/cli/utils/scaffold';
 
@@ -12,8 +10,7 @@ export const devCommand = new Command('dev')
   .option('--content <path>', 'Content directory')
   .option('--config <path>', 'Path to chronicle.yaml')
   .action(async options => {
-    const contentDir = resolveContentDir(options.content);
-    const configPath = resolveConfigPath(options.config);
+    const { contentDir, configPath } = await loadCLIConfig(options.config, { content: options.content });
     const port = parseInt(options.port, 10);
 
     await linkContent(contentDir);
diff --git a/packages/chronicle/src/cli/commands/serve.ts b/packages/chronicle/src/cli/commands/serve.ts
index 2861678..0af33a2 100644
--- a/packages/chronicle/src/cli/commands/serve.ts
+++ b/packages/chronicle/src/cli/commands/serve.ts
@@ -1,6 +1,6 @@
 import chalk from 'chalk';
 import { Command } from 'commander';
-import { resolveConfigPath, resolveContentDir } from '@/cli/utils/config';
+import { loadCLIConfig } from '@/cli/utils/config';
 import { PACKAGE_ROOT } from '@/cli/utils/resolve';
 import { linkContent } from '@/cli/utils/scaffold';
 
@@ -14,8 +14,10 @@ export const serveCommand = new Command('serve')
     'Deploy preset (vercel, cloudflare, node-server)'
   )
   .action(async options => {
-    const contentDir = resolveContentDir(options.content);
-    const configPath = resolveConfigPath(options.config);
+    const { contentDir, configPath, preset } = await loadCLIConfig(options.config, {
+      content: options.content,
+      preset: options.preset,
+    });
     const port = parseInt(options.port, 10);
     await linkContent(contentDir);
 
@@ -27,7 +29,7 @@ export const serveCommand = new Command('serve')
       projectRoot: process.cwd(),
       contentDir,
       configPath,
-      preset: options.preset
+      preset
     });
 
     console.log(chalk.cyan('Building for production...'));
diff --git a/packages/chronicle/src/cli/commands/start.ts b/packages/chronicle/src/cli/commands/start.ts
index 9739ed1..8603942 100644
--- a/packages/chronicle/src/cli/commands/start.ts
+++ b/packages/chronicle/src/cli/commands/start.ts
@@ -1,6 +1,6 @@
 import chalk from 'chalk';
 import { Command } from 'commander';
-import { resolveContentDir } from '@/cli/utils/config';
+import { loadCLIConfig } from '@/cli/utils/config';
 import { PACKAGE_ROOT } from '@/cli/utils/resolve';
 import { linkContent } from '@/cli/utils/scaffold';
 
@@ -9,7 +9,7 @@ export const startCommand = new Command('start')
   .option('-p, --port <port>', 'Port number', '3000')
   .option('--content <path>', 'Content directory')
   .action(async options => {
-    const contentDir = resolveContentDir(options.content);
+    const { contentDir, configPath } = await loadCLIConfig(undefined, { content: options.content });
     const port = parseInt(options.port, 10);
     await linkContent(contentDir);
 
@@ -18,7 +18,7 @@ export const startCommand = new Command('start')
     const { preview } = await import('vite');
     const { createViteConfig } = await import('@/server/vite-config');
 
-    const config = await createViteConfig({ packageRoot: PACKAGE_ROOT, projectRoot: process.cwd(), contentDir });
+    const config = await createViteConfig({ packageRoot: PACKAGE_ROOT, projectRoot: process.cwd(), contentDir, configPath });
     const server = await preview({
       ...config,
       preview: { port }
diff --git a/packages/chronicle/src/cli/utils/config.ts b/packages/chronicle/src/cli/utils/config.ts
index a3265ad..737ca13 100644
--- a/packages/chronicle/src/cli/utils/config.ts
+++ b/packages/chronicle/src/cli/utils/config.ts
@@ -2,17 +2,13 @@ import fs from 'node:fs/promises';
 import path from 'node:path';
 import chalk from 'chalk';
 import { parse } from 'yaml';
-import type { ChronicleConfig } from '@/types';
+import { chronicleConfigSchema, type ChronicleConfig } from '@/types';
 
 export interface CLIConfig {
   config: ChronicleConfig;
   configPath: string;
   contentDir: string;
-}
-
-export function resolveContentDir(contentFlag?: string): string {
-  if (contentFlag) return path.resolve(contentFlag);
-  return path.resolve('content');
+  preset?: string;
 }
 
 export function resolveConfigPath(configPath?: string): string | undefined {
@@ -20,27 +16,56 @@ export function resolveConfigPath(configPath?: string): string | undefined {
   return undefined;
 }
 
-async function readConfig(configPath: string): Promise<ChronicleConfig> {
-  try {
-    const raw = await fs.readFile(configPath, 'utf-8');
-    return parse(raw) as ChronicleConfig;
-  } catch (error) {
-    const err = error as NodeJS.ErrnoException;
-    if (err.code === 'ENOENT') {
+async function readConfig(configPath: string): Promise<string> {
+  return fs.readFile(configPath, 'utf-8').catch((error: NodeJS.ErrnoException) => {
+    if (error.code === 'ENOENT') {
       console.log(chalk.red(`Error: chronicle.yaml not found at '${configPath}'`));
       console.log(chalk.gray("Run 'chronicle init' to create one"));
     } else {
-      console.log(chalk.red(`Error: Invalid YAML in '${configPath}'`));
-      console.log(chalk.gray(err.message));
+      console.log(chalk.red(`Error: Failed to read '${configPath}'`));
+      console.log(chalk.gray(error.message));
+    }
+    process.exit(1);
+  });
+}
+
+function validateConfig(raw: string, configPath: string): ChronicleConfig {
+  const parsed = parse(raw);
+  const result = chronicleConfigSchema.safeParse(parsed);
+
+  if (!result.success) {
+    console.log(chalk.red(`Error: Invalid chronicle.yaml at '${configPath}'`));
+    for (const issue of result.error.issues) {
+      const path = issue.path.join('.');
+      console.log(chalk.gray(`  ${path ? `${path}: ` : ''}${issue.message}`));
     }
     process.exit(1);
   }
+
+  return result.data;
+}
+
+export function resolveContentDir(config: ChronicleConfig, contentFlag?: string): string {
+  if (contentFlag) return path.resolve(contentFlag);
+  if (config.content) return path.resolve(config.content);
+  return path.resolve('content');
+}
+
+export function resolvePreset(config: ChronicleConfig, presetFlag?: string): string | undefined {
+  return presetFlag ?? config.preset;
 }
 
-export async function loadCLIConfig(contentDir: string, configPath?: string): Promise<CLIConfig> {
+export async function loadCLIConfig(
+  configPath?: string,
+  options?: { content?: string; preset?: string }
+): Promise<CLIConfig> {
   const resolvedConfigPath = resolveConfigPath(configPath)
     ?? path.join(process.cwd(), 'chronicle.yaml');
 
-  const config = await readConfig(resolvedConfigPath);
-  return { config, configPath: resolvedConfigPath, contentDir };
+  const raw = await readConfig(resolvedConfigPath);
+  const config = validateConfig(raw, resolvedConfigPath);
+  const contentDir = resolveContentDir(config, options?.content);
+  const preset = resolvePreset(config, options?.preset);
+
+  return { config, configPath: resolvedConfigPath, contentDir, preset };
 }
diff --git a/packages/chronicle/src/types/config.ts b/packages/chronicle/src/types/config.ts
index 510643b..825b381 100644
--- a/packages/chronicle/src/types/config.ts
+++ b/packages/chronicle/src/types/config.ts
@@ -1,80 +1,99 @@
-export interface ChronicleConfig {
-  title: string
-  description?: string
-  url?: string
-  logo?: LogoConfig
-  theme?: ThemeConfig
-  navigation?: NavigationConfig
-  search?: SearchConfig
-  footer?: FooterConfig
-  api?: ApiConfig[]
-  llms?: LlmsConfig
-  analytics?: AnalyticsConfig
-}
+import { z } from 'zod'
 
-export interface LlmsConfig {
-  enabled?: boolean
-}
+const logoSchema = z.object({
+  light: z.string().optional(),
+  dark: z.string().optional(),
+})
 
-export interface AnalyticsConfig {
-  enabled?: boolean
-  googleAnalytics?: GoogleAnalyticsConfig
-}
+const themeSchema = z.object({
+  name: z.enum(['default', 'paper']),
+  colors: z.record(z.string(), z.string()).optional(),
+})
 
-export interface GoogleAnalyticsConfig {
-  measurementId: string
-}
+const navLinkSchema = z.object({
+  label: z.string(),
+  href: z.string(),
+})
 
-export interface ApiConfig {
-  name: string
-  spec: string
-  basePath: string
-  server: ApiServerConfig
-  auth?: ApiAuthConfig
-}
+const socialLinkSchema = z.object({
+  type: z.string(),
+  href: z.string(),
+})
 
-export interface ApiServerConfig {
-  url: string
-  description?: string
-}
+const navigationSchema = z.object({
+  links: z.array(navLinkSchema).optional(),
+  social: z.array(socialLinkSchema).optional(),
+})
 
-export interface ApiAuthConfig {
-  type: string
-  header: string
-  placeholder?: string
-}
+const searchSchema = z.object({
+  enabled: z.boolean().optional(),
+  placeholder: z.string().optional(),
+})
 
-export interface LogoConfig {
-  light?: string
-  dark?: string
-}
+const apiServerSchema = z.object({
+  url: z.string(),
+  description: z.string().optional(),
+})
 
-export interface ThemeConfig {
-  name: 'default' | 'paper'
-  colors?: Record<string, string>
-}
+const apiAuthSchema = z.object({
+  type: z.string(),
+  header: z.string(),
+  placeholder: z.string().optional(),
+})
 
-export interface NavigationConfig {
-  links?: NavLink[]
-  social?: SocialLink[]
-}
+const apiSchema = z.object({
+  name: z.string(),
+  spec: z.string(),
+  basePath: z.string(),
+  server: apiServerSchema,
+  auth: apiAuthSchema.optional(),
+})
 
-export interface NavLink {
-  label: string
-  href: string
-}
+const footerSchema = z.object({
+  copyright: z.string().optional(),
+  links: z.array(navLinkSchema).optional(),
+})
 
-export interface SocialLink {
-  type: 'github' | 'twitter' | 'discord' | string
-  href: string
-}
+const llmsSchema = z.object({
+  enabled: z.boolean().optional(),
+})
 
-export interface SearchConfig {
-  enabled?: boolean
-  placeholder?: string
-}
+const googleAnalyticsSchema = z.object({
+  measurementId: z.string(),
+})
 
-export interface FooterConfig {
-  copyright?: string
-  links?: NavLink[]
-}
+const analyticsSchema = z.object({
+  enabled: z.boolean().optional(),
+  googleAnalytics: googleAnalyticsSchema.optional(),
+})
+
+export const chronicleConfigSchema = z.object({
+  title: z.string(),
+  description: z.string().optional(),
+  url: z.string().optional(),
+  content: z.string().optional(),
+  preset: z.string().optional(),
+  logo: logoSchema.optional(),
+  theme: themeSchema.optional(),
+  navigation: navigationSchema.optional(),
+  search: searchSchema.optional(),
+  footer: footerSchema.optional(),
+  api: z.array(apiSchema).optional(),
+  llms: llmsSchema.optional(),
+  analytics: analyticsSchema.optional(),
+})
+
+export type ChronicleConfig = z.infer<typeof chronicleConfigSchema>
+export type LogoConfig = z.infer<typeof logoSchema>
+export type ThemeConfig = z.infer<typeof themeSchema>
+export type NavigationConfig = z.infer<typeof navigationSchema>
+export type NavLink = z.infer<typeof navLinkSchema>
+export type SocialLink = z.infer<typeof socialLinkSchema>
+export type SearchConfig = z.infer<typeof searchSchema>
+export type ApiConfig = z.infer<typeof apiSchema>
+export type ApiServerConfig = z.infer<typeof apiServerSchema>
+export type ApiAuthConfig = z.infer<typeof apiAuthSchema>
+export type FooterConfig = z.infer<typeof footerSchema>
+export type LlmsConfig = z.infer<typeof llmsSchema>
+export type AnalyticsConfig = z.infer<typeof analyticsSchema>
+export type GoogleAnalyticsConfig = z.infer<typeof googleAnalyticsSchema>