diff --git a/index.js b/index.js
index 3a062db..aa9d6f4 100644
--- a/index.js
+++ b/index.js
@@ -2,12 +2,13 @@
  * @import { DomStackOpts as DomStackOpts, Results, SiteData } from './lib/builder.js'
  * @import { Stats } from 'node:fs'
  * @import { FSWatcher } from 'chokidar'
- * @import { AsyncLayoutFunction, LayoutFunction } from './lib/build-pages/page-data.js'
- * @import { PageFunction, AsyncPageFunction } from './lib/build-pages/page-builders/page-writer.js'
+ * @import { AsyncLayoutFunction, LayoutFunction, LayoutFunctionParams } from './lib/build-pages/page-data.js'
+ * @import { PageFunction, AsyncPageFunction, PageFunctionParams } from './lib/build-pages/page-builders/page-writer.js'
  * @import { TemplateFunction } from './lib/build-pages/page-builders/template-builder.js'
  * @import { TemplateAsyncIterator } from './lib/build-pages/page-builders/template-builder.js'
  * @import { TemplateOutputOverride } from './lib/build-pages/page-builders/template-builder.js'
- * @import { GlobalDataFunction, AsyncGlobalDataFunction, WorkerBuildStepResult } from './lib/build-pages/index.js'
+ * @import { TemplateFunctionParams } from './lib/build-pages/page-builders/template-builder.js'
+ * @import { GlobalDataFunction, AsyncGlobalDataFunction, WorkerBuildStepResult, GlobalDataFunctionParams } from './lib/build-pages/index.js'
  * @import { BuildOptions, BuildContext } from 'esbuild'
  * @import { PageInfo, TemplateInfo } from './lib/identify-pages.js'
 */
@@ -49,6 +50,8 @@ import { resolveVars } from './lib/build-pages/resolve-vars.js'
 import { ensureDest } from './lib/helpers/ensure-dest.js'
 import { DomStackAggregateError } from './lib/helpers/domstack-aggregate-error.js'
 
+export { PageData } from './lib/build-pages/page-data.js'
+
 /**
  * @typedef {BuildOptions} BuildOptions
  */
@@ -103,6 +106,36 @@ import { DomStackAggregateError } from './lib/helpers/domstack-aggregate-error.j
  * @typedef {TemplateOutputOverride} TemplateOutputOverride
  */
 
+/**
+ * @typedef {PageInfo} PageInfo
+ */
+
+/**
+ * @typedef {TemplateInfo} TemplateInfo
+ */
+
+/**
+ * @template {Record<string, any>} T - The type of variables passed to the layout function
+ * @template [U=any] U - The return type of the page function
+ * @template [V=string] V - The return type of the layout function
+ * @typedef {LayoutFunctionParams<T, U, V>} LayoutFunctionParams
+ */
+
+/**
+ * @typedef {GlobalDataFunctionParams} GlobalDataFunctionParams
+ */
+
+/**
+ * @template {Record<string, any>} T - The type of variables passed to the page function
+ * @template [U=any] U - The return type of the page function
+ * @typedef {PageFunctionParams<T, U>} PageFunctionParams
+ */
+
+/**
+ * @template {Record<string, any>} [T=Record<string, any>] - The type of variables for the template function
+ * @typedef {TemplateFunctionParams<T>} TemplateFunctionParams
+ */
+
 const DEFAULT_IGNORES = /** @type {const} */ ([
   '.*',
   'coverage',
diff --git a/lib/build-pages/page-builders/template-builder.js b/lib/build-pages/page-builders/template-builder.js
index cdd4bf4..d055aa8 100644
--- a/lib/build-pages/page-builders/template-builder.js
+++ b/lib/build-pages/page-builders/template-builder.js
@@ -11,6 +11,16 @@ import { writeFile, mkdir } from 'fs/promises'
  *   content: string
  * }} TemplateOutputOverride */
 
+/**
+ * The parameters object passed to a {@link TemplateFunction} or {@link TemplateAsyncIterator}.
+ *
+ * @template {Record<string, any>} [T=Record<string, any>] - The type of variables for the template
+ * @typedef {object} TemplateFunctionParams
+ * @property {T} vars - All of the site globalVars.
+ * @property {TemplateInfo} template - Info about the current template.
+ * @property {PageData<T, any, string>[]} pages - An array of info about every page.
+ */
+
 /**
  * Callback for rendering a template.
  *
@@ -24,16 +34,11 @@ import { writeFile, mkdir } from 'fs/promises'
  *  } - The results of a template build
  */
 
-/**
- * @template {Record<string, any>} T - The type of variables for the template function parameters
- * @typedef {Parameters<TemplateFunction<T>>} TemplateFunctionParams
-*/
-
 /**
  * Callback for rendering a template with an async iterator.
  * @template T - The type of variables for the template async iterator
  * @callback TemplateAsyncIterator
- * @param {TemplateFunctionParams<T>[0]} params - Parameters of the template function.
+ * @param {TemplateFunctionParams<T>} params - Parameters of the template function.
  * @returns {AsyncIterable<TemplateOutputOverride>}
  */
 
diff --git a/test-cases/type-exports/index.test.js b/test-cases/type-exports/index.test.js
new file mode 100644
index 0000000..ac0ab5d
--- /dev/null
+++ b/test-cases/type-exports/index.test.js
@@ -0,0 +1,20 @@
+// @ts-check
+import { test } from 'node:test'
+import assert from 'node:assert'
+import { PageData } from '../../index.js'
+
+/**
+ * Smoke test that all public types are importable from the package entry point.
+ * The type imports below are verified by TypeScript at compile time via `npm run test:tsc`.
+ *
+ * @typedef {import('../../index.js').PageInfo} PageInfo
+ * @typedef {import('../../index.js').TemplateInfo} TemplateInfo
+ * @typedef {import('../../index.js').LayoutFunctionParams<any>} LayoutFunctionParams
+ * @typedef {import('../../index.js').GlobalDataFunctionParams} GlobalDataFunctionParams
+ * @typedef {import('../../index.js').PageFunctionParams<any>} PageFunctionParams
+ * @typedef {import('../../index.js').TemplateFunctionParams} TemplateFunctionParams
+ */
+
+test('PageData is importable from the package entry point', () => {
+  assert.strictEqual(typeof PageData, 'function', 'PageData is a class')
+})