From 082fc52cf359a8b74985dd5c4605a84aa6b5547d Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 12 Nov 2025 15:53:49 +0100
Subject: [PATCH 01/29] feat: loader.getSchemaContext()

---
 packages/astro/src/content/content-layer.ts   |  4 +-
 packages/astro/src/content/loaders/types.ts   | 19 ++++--
 packages/astro/src/content/types-generator.ts | 67 +++++++++++--------
 packages/astro/src/content/utils.ts           | 23 ++++---
 4 files changed, 70 insertions(+), 43 deletions(-)

diff --git a/packages/astro/src/content/content-layer.ts b/packages/astro/src/content/content-layer.ts
index 17335f54f1e5..f55fbbe46f92 100644
--- a/packages/astro/src/content/content-layer.ts
+++ b/packages/astro/src/content/content-layer.ts
@@ -253,8 +253,8 @@ class ContentLayer {
 
 				if (!schema && typeof collection.loader === 'object') {
 					schema = collection.loader.schema;
-					if (typeof schema === 'function') {
-						schema = await schema();
+					if (!schema && collection.loader.getSchemaContext) {
+						({ schema } = await collection.loader.getSchemaContext());
 					}
 				}
 
diff --git a/packages/astro/src/content/loaders/types.ts b/packages/astro/src/content/loaders/types.ts
index 6939357a5620..c48b35c56a98 100644
--- a/packages/astro/src/content/loaders/types.ts
+++ b/packages/astro/src/content/loaders/types.ts
@@ -49,14 +49,25 @@ export interface LoaderContext {
 	entryTypes: Map<string, ContentEntryType>;
 }
 
-export interface Loader {
+export type Loader = {
 	/** Unique name of the loader, e.g. the npm package name */
 	name: string;
 	/** Do the actual loading of the data */
 	load: (context: LoaderContext) => Promise<void>;
-	/** Optionally, define the schema of the data. Will be overridden by user-defined schema */
-	schema?: ZodSchema | Promise<ZodSchema> | (() => ZodSchema | Promise<ZodSchema>);
-}
+} & (
+	| {
+			/** Optionally, define the schema of the data. Will be overridden by user-defined schema */
+			schema?: ZodSchema;
+			getSchemaContext?: never;
+	  }
+	| {
+			schema?: never;
+			getSchemaContext: () => Promise<{
+				schema: ZodSchema;
+				types: string;
+			}>;
+	  }
+);
 
 export interface LoadEntryContext<TEntryFilter = never> {
 	filter: TEntryFilter extends never ? { id: string } : TEntryFilter;
diff --git a/packages/astro/src/content/types-generator.ts b/packages/astro/src/content/types-generator.ts
index de246950a7f8..456c54b6f88a 100644
--- a/packages/astro/src/content/types-generator.ts
+++ b/packages/astro/src/content/types-generator.ts
@@ -342,13 +342,13 @@ function normalizeConfigPath(from: string, to: string) {
 	return `"${isRelativePath(configPath) ? '' : './'}${normalizedPath}"` as const;
 }
 
-const schemaCache = new Map<string, ZodSchema>();
+const schemaContextResultCache = new Map<string, { schema: ZodSchema; types: string }>();
 
-async function getContentLayerSchema<T extends keyof ContentConfig['collections']>(
+async function getSchemaContextResult<T extends keyof ContentConfig['collections']>(
 	collection: ContentConfig['collections'][T],
 	collectionKey: T,
-): Promise<ZodSchema | undefined> {
-	const cached = schemaCache.get(collectionKey);
+) {
+	const cached = schemaContextResultCache.get(collectionKey);
 	if (cached) {
 		return cached;
 	}
@@ -356,19 +356,29 @@ async function getContentLayerSchema<T extends keyof ContentConfig['collections'
 	if (
 		collection?.type === CONTENT_LAYER_TYPE &&
 		typeof collection.loader === 'object' &&
-		collection.loader.schema
+		!collection.loader.schema &&
+		collection.loader.getSchemaContext
 	) {
-		let schema = collection.loader.schema;
-		if (typeof schema === 'function') {
-			schema = await schema();
-		}
-		if (schema) {
-			schemaCache.set(collectionKey, await schema);
-			return schema;
-		}
+		const result = await collection.loader.getSchemaContext();
+		schemaContextResultCache.set(collectionKey, result);
+		return result;
 	}
 }
 
+async function getContentLayerSchema<T extends keyof ContentConfig['collections']>(
+	collection: ContentConfig['collections'][T],
+	collectionKey: T,
+): Promise<ZodSchema | undefined> {
+	if (collection?.type !== CONTENT_LAYER_TYPE || typeof collection.loader === 'function') {
+		return;
+	}
+	if (collection.loader.schema) {
+		return collection.loader.schema;
+	}
+	const result = await getSchemaContextResult(collection, collectionKey);
+	return result?.schema;
+}
+
 async function typeForCollection<T extends keyof ContentConfig['collections']>(
 	collection: ContentConfig['collections'][T] | undefined,
 	collectionKey: T,
@@ -376,24 +386,20 @@ async function typeForCollection<T extends keyof ContentConfig['collections']>(
 	if (collection?.schema) {
 		return `InferEntrySchema<${collectionKey}>`;
 	}
-	if (!collection?.type) {
+	if (!collection?.type || typeof collection.loader === 'function') {
 		return 'any';
 	}
-	const schema = await getContentLayerSchema(collection, collectionKey);
-	if (!schema) {
-		return 'any';
+	if (collection.loader.schema) {
+		// TODO: this only works if a loader has info about its schema
+		return `InferLoaderSchema<${collectionKey}>`;
 	}
-	try {
-		const zodToTs = await import('zod-to-ts');
-		const ast = zodToTs.zodToTs(schema);
-		return zodToTs.printNode(ast.node);
-	} catch (err: any) {
-		// zod-to-ts is sad if we don't have TypeScript installed, but that's fine as we won't be needing types in that case
-		if (err.message.includes("Cannot find package 'typescript'")) {
-			return 'any';
-		}
-		throw err;
+	const result = await getSchemaContextResult(collection, collectionKey);
+	if (!result) {
+		return 'any';
 	}
+	// TODO: inject result.types
+	const relativePath = 'TODO:';
+	return `import(${relativePath}).Collection`;
 }
 
 async function writeContentFiles({
@@ -487,7 +493,12 @@ async function writeContentFiles({
 			const key = JSON.parse(collectionKey);
 
 			contentCollectionManifest.collections.push({
-				hasSchema: Boolean(collectionConfig?.schema || schemaCache.has(collectionKey)),
+				hasSchema: Boolean(
+					collectionConfig &&
+						(collectionConfig.schema ||
+							(typeof collectionConfig.loader !== 'function' &&
+								(collectionConfig.loader.schema || schemaContextResultCache.has(collectionKey)))),
+				),
 				name: key,
 			});
 
diff --git a/packages/astro/src/content/utils.ts b/packages/astro/src/content/utils.ts
index cbd43317f140..11e582ff6356 100644
--- a/packages/astro/src/content/utils.ts
+++ b/packages/astro/src/content/utils.ts
@@ -7,7 +7,7 @@ import colors from 'picocolors';
 import type { PluginContext } from 'rollup';
 import type { ViteDevServer } from 'vite';
 import xxhash from 'xxhash-wasm';
-import { z } from 'zod';
+import { type ZodSchema, z } from 'zod';
 import { AstroError, AstroErrorData, errorMap, MarkdownError } from '../core/errors/index.js';
 import { isYAMLException } from '../core/errors/utils.js';
 import type { Logger } from '../core/logger/core.js';
@@ -60,14 +60,19 @@ const collectionConfigParser = z.union([
 			z.function(),
 			z.object({
 				name: z.string(),
-				load: z.function().args(z.custom<LoaderContext>()).returns(
-					z.custom<{
-						schema?: any;
-						types?: string;
-					} | void>(),
-				),
-				schema: z.any().optional(),
-				render: z.function(z.tuple([z.any()], z.unknown())).optional(),
+				load: z.function().args(z.custom<LoaderContext>()).returns(z.promise(z.void())),
+				schema: z.custom<ZodSchema>((v) => '_def' in v).optional(),
+				getSchemaContext: z
+					.function()
+					.returns(
+						z.promise(
+							z.object({
+								schema: z.custom<ZodSchema>((v) => '_def' in v),
+								types: z.string(),
+							}),
+						),
+					)
+					.optional(),
 			}),
 		]),
 	}),

From fc7a78547194d30848ccaf93c9a2f787e173d749 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 12 Nov 2025 16:29:25 +0100
Subject: [PATCH 02/29] wip

---
 packages/astro/src/content/types-generator.ts | 38 ++++++++++++++-----
 packages/astro/templates/content/types.d.ts   |  3 ++
 2 files changed, 32 insertions(+), 9 deletions(-)

diff --git a/packages/astro/src/content/types-generator.ts b/packages/astro/src/content/types-generator.ts
index 456c54b6f88a..f57e4f4f8da1 100644
--- a/packages/astro/src/content/types-generator.ts
+++ b/packages/astro/src/content/types-generator.ts
@@ -11,6 +11,7 @@ import type { Logger } from '../core/logger/core.js';
 import { isRelativePath } from '../core/path.js';
 import type { AstroSettings } from '../types/astro.js';
 import type { ContentEntryType } from '../types/public/content.js';
+import type { InjectedType } from '../types/public/integrations.js';
 import {
 	COLLECTIONS_DIR,
 	CONTENT_LAYER_TYPE,
@@ -382,24 +383,29 @@ async function getContentLayerSchema<T extends keyof ContentConfig['collections'
 async function typeForCollection<T extends keyof ContentConfig['collections']>(
 	collection: ContentConfig['collections'][T] | undefined,
 	collectionKey: T,
-): Promise<string> {
+): Promise<{ type: string; injectedType?: InjectedType }> {
 	if (collection?.schema) {
-		return `InferEntrySchema<${collectionKey}>`;
+		return { type: `InferEntrySchema<${collectionKey}>` };
 	}
 	if (!collection?.type || typeof collection.loader === 'function') {
-		return 'any';
+		return { type: 'any' };
 	}
 	if (collection.loader.schema) {
 		// TODO: this only works if a loader has info about its schema
-		return `InferLoaderSchema<${collectionKey}>`;
+		return { type: `InferLoaderSchema<${collectionKey}>` };
 	}
 	const result = await getSchemaContextResult(collection, collectionKey);
 	if (!result) {
-		return 'any';
+		return { type: 'any' };
 	}
-	// TODO: inject result.types
-	const relativePath = 'TODO:';
-	return `import(${relativePath}).Collection`;
+	const filename = `loaders/${collectionKey}.ts`;
+	return {
+		type: `import(${filename}).Collection`,
+		injectedType: {
+			filename,
+			content: result.types,
+		},
+	};
 }
 
 async function writeContentFiles({
@@ -466,7 +472,21 @@ async function writeContentFiles({
 			return;
 		}
 
-		const dataType = await typeForCollection(collectionConfig, collectionKey);
+		const { type: dataType, injectedType } = await typeForCollection(
+			collectionConfig,
+			collectionKey,
+		);
+
+		if (injectedType) {
+			if (settings.injectedTypes.some((t) => t.filename === CONTENT_TYPES_FILE)) {
+				// If it's the first time, we inject types the usual way. sync() will handle creating files and references. If it's not the first time, we just override the dts content
+				const url = new URL(injectedType.filename, settings.dotAstroDir);
+				await fs.promises.mkdir(path.dirname(fileURLToPath(url)), { recursive: true });
+				await fs.promises.writeFile(url, injectedType.content, 'utf-8');
+			} else {
+				settings.injectedTypes.push(injectedType);
+			}
+		}
 
 		dataTypesStr += `${collectionKey}: Record<string, {\n  id: string;\n  body?: string;\n  collection: ${collectionKey};\n  data: ${dataType};\n  rendered?: RenderedContent;\n  filePath?: string;\n}>;\n`;
 
diff --git a/packages/astro/templates/content/types.d.ts b/packages/astro/templates/content/types.d.ts
index 12d008e3d6e3..425a2017a277 100644
--- a/packages/astro/templates/content/types.d.ts
+++ b/packages/astro/templates/content/types.d.ts
@@ -104,6 +104,9 @@ declare module 'astro:content' {
 	type InferEntrySchema<C extends keyof DataEntryMap> = import('astro/zod').infer<
 		ReturnTypeOrOriginal<Required<ContentConfig['collections'][C]>['schema']>
 	>;
+	type InferLoaderSchema<C extends keyof DataEntryMap> = import('astro/zod').infer<
+		ReturnTypeOrOriginal<Required<ContentConfig['collections'][C]>['loader']['schema']>
+	>;
 
 	type DataEntryMap = {
 		// @@DATA_ENTRY_MAP@@

From 865e64ba008d3b1cc8f73871447168ee0cbd0220 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 12 Nov 2025 16:31:18 +0100
Subject: [PATCH 03/29] wip

---
 packages/astro/src/content/loaders/config.ts  | 6 ++++++
 packages/astro/src/content/loaders/index.ts   | 1 +
 packages/astro/src/content/loaders/types.ts   | 4 ++--
 packages/astro/src/content/types-generator.ts | 1 -
 4 files changed, 9 insertions(+), 3 deletions(-)
 create mode 100644 packages/astro/src/content/loaders/config.ts

diff --git a/packages/astro/src/content/loaders/config.ts b/packages/astro/src/content/loaders/config.ts
new file mode 100644
index 000000000000..f2e9f5d54e47
--- /dev/null
+++ b/packages/astro/src/content/loaders/config.ts
@@ -0,0 +1,6 @@
+import type { ZodSchema } from 'zod';
+import type { Loader } from './types.js';
+
+export function defineContentLoader<T extends ZodSchema>(loader: Loader<T>) {
+	return loader;
+}
diff --git a/packages/astro/src/content/loaders/index.ts b/packages/astro/src/content/loaders/index.ts
index 30b4bfbe5334..51a2de9fb748 100644
--- a/packages/astro/src/content/loaders/index.ts
+++ b/packages/astro/src/content/loaders/index.ts
@@ -1,3 +1,4 @@
+export { defineContentLoader } from './config.js';
 export { file } from './file.js';
 export { glob } from './glob.js';
 export * from './types.js';
diff --git a/packages/astro/src/content/loaders/types.ts b/packages/astro/src/content/loaders/types.ts
index c48b35c56a98..14beae56b666 100644
--- a/packages/astro/src/content/loaders/types.ts
+++ b/packages/astro/src/content/loaders/types.ts
@@ -49,7 +49,7 @@ export interface LoaderContext {
 	entryTypes: Map<string, ContentEntryType>;
 }
 
-export type Loader = {
+export type Loader<T extends ZodSchema = ZodSchema> = {
 	/** Unique name of the loader, e.g. the npm package name */
 	name: string;
 	/** Do the actual loading of the data */
@@ -57,7 +57,7 @@ export type Loader = {
 } & (
 	| {
 			/** Optionally, define the schema of the data. Will be overridden by user-defined schema */
-			schema?: ZodSchema;
+			schema?: T;
 			getSchemaContext?: never;
 	  }
 	| {
diff --git a/packages/astro/src/content/types-generator.ts b/packages/astro/src/content/types-generator.ts
index f57e4f4f8da1..3d8786532842 100644
--- a/packages/astro/src/content/types-generator.ts
+++ b/packages/astro/src/content/types-generator.ts
@@ -391,7 +391,6 @@ async function typeForCollection<T extends keyof ContentConfig['collections']>(
 		return { type: 'any' };
 	}
 	if (collection.loader.schema) {
-		// TODO: this only works if a loader has info about its schema
 		return { type: `InferLoaderSchema<${collectionKey}>` };
 	}
 	const result = await getSchemaContextResult(collection, collectionKey);

From 144c7916e8e98dd74e5288fa494a4657ac928ff2 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 12 Nov 2025 16:33:09 +0100
Subject: [PATCH 04/29] wip

---
 packages/astro/src/content/loaders/file.ts | 9 +++++----
 packages/astro/src/content/loaders/glob.ts | 8 ++++----
 2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/packages/astro/src/content/loaders/file.ts b/packages/astro/src/content/loaders/file.ts
index c1b4b2a075a6..09b69f148884 100644
--- a/packages/astro/src/content/loaders/file.ts
+++ b/packages/astro/src/content/loaders/file.ts
@@ -5,7 +5,8 @@ import toml from 'smol-toml';
 import { FileGlobNotSupported, FileParserNotFound } from '../../core/errors/errors-data.js';
 import { AstroError } from '../../core/errors/index.js';
 import { posixRelative } from '../utils.js';
-import type { Loader, LoaderContext } from './types.js';
+import { defineContentLoader } from './config.js';
+import type { LoaderContext } from './types.js';
 
 interface FileOptions {
 	/**
@@ -22,7 +23,7 @@ interface FileOptions {
  * @param fileName The path to the JSON file to load, relative to the content directory.
  * @param options Additional options for the file loader
  */
-export function file(fileName: string, options?: FileOptions): Loader {
+export function file(fileName: string, options?: FileOptions) {
 	if (fileName.includes('*')) {
 		throw new AstroError(FileGlobNotSupported);
 	}
@@ -102,7 +103,7 @@ export function file(fileName: string, options?: FileOptions): Loader {
 		}
 	}
 
-	return {
+	return defineContentLoader({
 		name: 'file-loader',
 		load: async (context) => {
 			const { config, logger, watcher } = context;
@@ -125,5 +126,5 @@ export function file(fileName: string, options?: FileOptions): Loader {
 				}
 			});
 		},
-	};
+	});
 }
diff --git a/packages/astro/src/content/loaders/glob.ts b/packages/astro/src/content/loaders/glob.ts
index 99d0dbaca84f..a94715104c50 100644
--- a/packages/astro/src/content/loaders/glob.ts
+++ b/packages/astro/src/content/loaders/glob.ts
@@ -8,7 +8,7 @@ import { glob as tinyglobby } from 'tinyglobby';
 import type { ContentEntryRenderFunction, ContentEntryType } from '../../types/public/content.js';
 import type { RenderedContent } from '../data-store.js';
 import { getContentEntryIdAndSlug, posixRelative } from '../utils.js';
-import type { Loader } from './types.js';
+import { defineContentLoader } from './config.js';
 
 interface GenerateIdOptions {
 	/** The path to the entry file, relative to the base directory. */
@@ -57,7 +57,7 @@ function checkPrefix(pattern: string | Array<string>, prefix: string) {
  * @param pattern A glob pattern to match files, relative to the content directory.
  */
 
-export function glob(globOptions: GlobOptions): Loader {
+export function glob(globOptions: GlobOptions) {
 	if (checkPrefix(globOptions.pattern, '../')) {
 		throw new Error(
 			'Glob patterns cannot start with `../`. Set the `base` option to a parent directory instead.',
@@ -73,7 +73,7 @@ export function glob(globOptions: GlobOptions): Loader {
 
 	const fileToIdMap = new Map<string, string>();
 
-	return {
+	return defineContentLoader({
 		name: 'glob-loader',
 		load: async ({ config, logger, watcher, parseData, store, generateDigest, entryTypes }) => {
 			const renderFunctionByContentType = new WeakMap<
@@ -315,5 +315,5 @@ export function glob(globOptions: GlobOptions): Loader {
 				}
 			});
 		},
-	};
+	});
 }

From 0ecc8d5775d342a79f4b67a359e7f41b2df8ab4a Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 13 Nov 2025 11:34:20 +0100
Subject: [PATCH 05/29] fix

---
 examples/blog/src/content.config.ts           |  57 ++++++--
 packages/astro/src/content/config.ts          | 124 ++++++++----------
 packages/astro/src/content/loaders/config.ts  |   2 +-
 packages/astro/src/content/loaders/types.ts   |  40 +++---
 packages/astro/src/content/types-generator.ts |   4 +-
 packages/astro/templates/content/types.d.ts   |   2 +-
 packages/astro/types/content.d.ts             |  12 +-
 7 files changed, 129 insertions(+), 112 deletions(-)

diff --git a/examples/blog/src/content.config.ts b/examples/blog/src/content.config.ts
index ce37c7f6ff34..64c9967b0781 100644
--- a/examples/blog/src/content.config.ts
+++ b/examples/blog/src/content.config.ts
@@ -1,19 +1,54 @@
 import { defineCollection, z } from 'astro:content';
-import { glob } from 'astro/loaders';
+import { defineContentLoader, glob } from 'astro/loaders';
+
+const test = (options: Parameters<typeof glob>[0]) =>
+	defineContentLoader({
+		name: 'test',
+		load: glob(options).load,
+		// schema: z.object({
+		// 	title: z.string(),
+		// 	description: z.string(),
+		// 	// Transform string to Date object
+		// 	pubDate: z.coerce.date(),
+		// 	updatedDate: z.coerce.date().optional(),
+		// 	heroImage: z.string().optional(),
+		// }),
+		getSchemaContext: async () => {
+			return {
+				schema: z.object({
+					title: z.string(),
+					description: z.string(),
+					// Transform string to Date object
+					pubDate: z.coerce.date(),
+					updatedDate: z.coerce.date().optional(),
+					heroImage: z.string().optional(),
+				}),
+				types: `import type { ImageMetadata } from "astro";
+
+export interface Collection {
+	title: string;
+	description: string;
+	pubDate: Date;
+	updateDate: Date | undefined;
+	heroImage: ImageMetadata | undefined;
+}`,
+			};
+		},
+	});
 
 const blog = defineCollection({
 	// Load Markdown and MDX files in the `src/content/blog/` directory.
-	loader: glob({ base: './src/content/blog', pattern: '**/*.{md,mdx}' }),
+	loader: test({ base: './src/content/blog', pattern: '**/*.{md,mdx}' }),
 	// Type-check frontmatter using a schema
-	schema: ({ image }) =>
-		z.object({
-			title: z.string(),
-			description: z.string(),
-			// Transform string to Date object
-			pubDate: z.coerce.date(),
-			updatedDate: z.coerce.date().optional(),
-			heroImage: image().optional(),
-		}),
+	// schema: ({ image }) =>
+	// 	z.object({
+	// 		title: z.string(),
+	// 		description: z.string(),
+	// 		// Transform string to Date object
+	// 		pubDate: z.coerce.date(),
+	// 		updatedDate: z.coerce.date().optional(),
+	// 		heroImage: image().optional(),
+	// 	}),
 });
 
 export const collections = { blog };
diff --git a/packages/astro/src/content/config.ts b/packages/astro/src/content/config.ts
index e6424b5b7b10..373fa35326c8 100644
--- a/packages/astro/src/content/config.ts
+++ b/packages/astro/src/content/config.ts
@@ -71,29 +71,6 @@ export type BaseSchema = ZodType;
 
 export type SchemaContext = { image: ImageFunction };
 
-type ContentLayerConfig<S extends BaseSchema, TData extends { id: string } = { id: string }> = {
-	type?: 'content_layer';
-	schema?: S | ((context: SchemaContext) => S);
-	loader:
-		| Loader
-		| (() =>
-				| Array<TData>
-				| Promise<Array<TData>>
-				| Record<string, Omit<TData, 'id'> & { id?: string }>
-				| Promise<Record<string, Omit<TData, 'id'> & { id?: string }>>);
-};
-
-type DataCollectionConfig<S extends BaseSchema> = {
-	type: 'data';
-	schema?: S | ((context: SchemaContext) => S);
-};
-
-type ContentCollectionConfig<S extends BaseSchema> = {
-	type?: 'content';
-	schema?: S | ((context: SchemaContext) => S);
-	loader?: never;
-};
-
 export type LiveCollectionConfig<
 	L extends LiveLoader,
 	S extends BaseSchema | undefined = undefined,
@@ -103,10 +80,22 @@ export type LiveCollectionConfig<
 	loader: L;
 };
 
-export type CollectionConfig<S extends BaseSchema> =
-	| ContentCollectionConfig<S>
-	| DataCollectionConfig<S>
-	| ContentLayerConfig<S>;
+type LoaderConstraint<TData extends { id: string }> =
+	| Loader
+	| (() =>
+			| Array<TData>
+			| Promise<Array<TData>>
+			| Record<string, Omit<TData, 'id'> & { id?: string }>
+			| Promise<Record<string, Omit<TData, 'id'> & { id?: string }>>);
+
+export type CollectionConfig<
+	TSchema extends BaseSchema,
+	TLoader extends LoaderConstraint<{ id: string }>,
+> = {
+	type?: 'content_layer';
+	schema?: TSchema | ((context: SchemaContext) => TSchema);
+	loader: TLoader;
+};
 
 export function defineLiveCollection<
 	L extends LiveLoader,
@@ -167,44 +156,45 @@ export function defineLiveCollection<
 	return config;
 }
 
-export function defineCollection<S extends BaseSchema>(
-	config: CollectionConfig<S>,
-): CollectionConfig<S> {
-	const importerFilename = getImporterFilename();
-
-	if (importerFilename?.includes('live.config')) {
-		throw new AstroError({
-			...AstroErrorData.LiveContentConfigError,
-			message: AstroErrorData.LiveContentConfigError.message(
-				'Collections in a live config file must use `defineLiveCollection`.',
-				importerFilename,
-			),
-		});
-	}
-
-	if (!('loader' in config)) {
-		throw new AstroError({
-			...AstroErrorData.ContentCollectionMissingLoader,
-			message: AstroErrorData.ContentCollectionMissingLoader.message(importerFilename),
-		});
+export function defineCollection<
+		TSchema extends BaseSchema,
+		TLoader extends LoaderConstraint<{ id: string }>,
+	>(config: CollectionConfig<TSchema, TLoader>): CollectionConfig<TSchema, TLoader> {
+		const importerFilename = getImporterFilename();
+
+		if (importerFilename?.includes('live.config')) {
+			throw new AstroError({
+				...AstroErrorData.LiveContentConfigError,
+				message: AstroErrorData.LiveContentConfigError.message(
+					'Collections in a live config file must use `defineLiveCollection`.',
+					importerFilename,
+				),
+			});
+		}
+
+		if (!('loader' in config)) {
+			throw new AstroError({
+				...AstroErrorData.ContentCollectionMissingLoader,
+				message: AstroErrorData.ContentCollectionMissingLoader.message(importerFilename),
+			});
+		}
+
+		if (config.type && config.type !== CONTENT_LAYER_TYPE) {
+			throw new AstroError({
+				...AstroErrorData.ContentCollectionInvalidType,
+				message: AstroErrorData.ContentCollectionInvalidType.message(config.type, importerFilename),
+			});
+		}
+
+		if (
+			typeof config.loader === 'object' &&
+			typeof config.loader.load !== 'function' &&
+			('loadEntry' in config.loader || 'loadCollection' in config.loader)
+		) {
+			throw new AstroUserError(
+				`Live content collections must be defined in "src/live.config.ts" file. Check your collection definitions in "${importerFilename ?? 'your content config file'}" to ensure you are not using a live loader.`,
+			);
+		}
+		config.type = CONTENT_LAYER_TYPE;
+		return config;
 	}
-
-	if (config.type && config.type !== CONTENT_LAYER_TYPE) {
-		throw new AstroError({
-			...AstroErrorData.ContentCollectionInvalidType,
-			message: AstroErrorData.ContentCollectionInvalidType.message(config.type, importerFilename),
-		});
-	}
-
-	if (
-		typeof config.loader === 'object' &&
-		typeof config.loader.load !== 'function' &&
-		('loadEntry' in config.loader || 'loadCollection' in config.loader)
-	) {
-		throw new AstroUserError(
-			`Live content collections must be defined in "src/live.config.ts" file. Check your collection definitions in "${importerFilename ?? 'your content config file'}" to ensure you are not using a live loader.`,
-		);
-	}
-	config.type = CONTENT_LAYER_TYPE;
-	return config;
-}
diff --git a/packages/astro/src/content/loaders/config.ts b/packages/astro/src/content/loaders/config.ts
index f2e9f5d54e47..0616d7beb9ca 100644
--- a/packages/astro/src/content/loaders/config.ts
+++ b/packages/astro/src/content/loaders/config.ts
@@ -1,6 +1,6 @@
 import type { ZodSchema } from 'zod';
 import type { Loader } from './types.js';
 
-export function defineContentLoader<T extends ZodSchema>(loader: Loader<T>) {
+export function defineContentLoader<T extends ZodSchema | never = never>(loader: Loader<T>) {
 	return loader;
 }
diff --git a/packages/astro/src/content/loaders/types.ts b/packages/astro/src/content/loaders/types.ts
index 14beae56b666..8e37f9e5f470 100644
--- a/packages/astro/src/content/loaders/types.ts
+++ b/packages/astro/src/content/loaders/types.ts
@@ -49,25 +49,27 @@ export interface LoaderContext {
 	entryTypes: Map<string, ContentEntryType>;
 }
 
-export type Loader<T extends ZodSchema = ZodSchema> = {
-	/** Unique name of the loader, e.g. the npm package name */
-	name: string;
-	/** Do the actual loading of the data */
-	load: (context: LoaderContext) => Promise<void>;
-} & (
-	| {
-			/** Optionally, define the schema of the data. Will be overridden by user-defined schema */
-			schema?: T;
-			getSchemaContext?: never;
-	  }
-	| {
-			schema?: never;
-			getSchemaContext: () => Promise<{
-				schema: ZodSchema;
-				types: string;
-			}>;
-	  }
-);
+export type Loader<T extends ZodSchema = never> = {
+		/** Unique name of the loader, e.g. the npm package name */
+		name: string;
+		/** Do the actual loading of the data */
+		load: (context: LoaderContext) => Promise<void>;
+	} & ([T] extends [never]
+		?
+				| {
+						/** Optionally, define the schema of the data. Will be overridden by user-defined schema */
+						schema?: T;
+				  }
+				| {
+						getSchemaContext?: () => Promise<{
+							schema: ZodSchema;
+							types: string;
+						}>;
+				  }
+		: {
+				/** Optionally, define the schema of the data. Will be overridden by user-defined schema */
+				schema: T;
+			});
 
 export interface LoadEntryContext<TEntryFilter = never> {
 	filter: TEntryFilter extends never ? { id: string } : TEntryFilter;
diff --git a/packages/astro/src/content/types-generator.ts b/packages/astro/src/content/types-generator.ts
index 3d8786532842..b77dae648bf0 100644
--- a/packages/astro/src/content/types-generator.ts
+++ b/packages/astro/src/content/types-generator.ts
@@ -397,9 +397,9 @@ async function typeForCollection<T extends keyof ContentConfig['collections']>(
 	if (!result) {
 		return { type: 'any' };
 	}
-	const filename = `loaders/${collectionKey}.ts`;
+	const filename = `loaders/${collectionKey.slice(1,-1)}.ts`;
 	return {
-		type: `import(${filename}).Collection`,
+		type: `import("./${filename}").Collection`,
 		injectedType: {
 			filename,
 			content: result.types,
diff --git a/packages/astro/templates/content/types.d.ts b/packages/astro/templates/content/types.d.ts
index 425a2017a277..9caa399bc7af 100644
--- a/packages/astro/templates/content/types.d.ts
+++ b/packages/astro/templates/content/types.d.ts
@@ -105,7 +105,7 @@ declare module 'astro:content' {
 		ReturnTypeOrOriginal<Required<ContentConfig['collections'][C]>['schema']>
 	>;
 	type InferLoaderSchema<C extends keyof DataEntryMap> = import('astro/zod').infer<
-		ReturnTypeOrOriginal<Required<ContentConfig['collections'][C]>['loader']['schema']>
+		Required<ContentConfig['collections'][C]>['loader']['schema']
 	>;
 
 	type DataEntryMap = {
diff --git a/packages/astro/types/content.d.ts b/packages/astro/types/content.d.ts
index cb5b6d7360b8..36864a923e63 100644
--- a/packages/astro/types/content.d.ts
+++ b/packages/astro/types/content.d.ts
@@ -8,17 +8,7 @@ declare module 'astro:content' {
 		BaseSchema,
 		SchemaContext,
 	} from 'astro/content/config';
-
-	export function defineLiveCollection<
-		L extends import('astro/loaders').LiveLoader,
-		S extends import('astro/content/config').BaseSchema | undefined = undefined,
-	>(
-		config: import('astro/content/config').LiveCollectionConfig<L, S>,
-	): import('astro/content/config').LiveCollectionConfig<L, S>;
-
-	export function defineCollection<S extends import('astro/content/config').BaseSchema>(
-		config: import('astro/content/config').CollectionConfig<S>,
-	): import('astro/content/config').CollectionConfig<S>;
+	export { defineLiveCollection, defineCollection } from 'astro/content/config';
 
 	/** Run `astro dev` or `astro sync` to generate high fidelity types */
 	export const getEntryBySlug: (...args: any[]) => any;

From 85fb14a331a5d6cc0660f1f94a059ce4a6c84bb5 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 13 Nov 2025 11:35:36 +0100
Subject: [PATCH 06/29] chore: format

---
 packages/astro/src/content/config.ts          | 80 +++++++++----------
 packages/astro/src/content/loaders/types.ts   | 40 +++++-----
 packages/astro/src/content/types-generator.ts |  2 +-
 3 files changed, 61 insertions(+), 61 deletions(-)

diff --git a/packages/astro/src/content/config.ts b/packages/astro/src/content/config.ts
index 373fa35326c8..a148d8ced405 100644
--- a/packages/astro/src/content/config.ts
+++ b/packages/astro/src/content/config.ts
@@ -157,44 +157,44 @@ export function defineLiveCollection<
 }
 
 export function defineCollection<
-		TSchema extends BaseSchema,
-		TLoader extends LoaderConstraint<{ id: string }>,
-	>(config: CollectionConfig<TSchema, TLoader>): CollectionConfig<TSchema, TLoader> {
-		const importerFilename = getImporterFilename();
-
-		if (importerFilename?.includes('live.config')) {
-			throw new AstroError({
-				...AstroErrorData.LiveContentConfigError,
-				message: AstroErrorData.LiveContentConfigError.message(
-					'Collections in a live config file must use `defineLiveCollection`.',
-					importerFilename,
-				),
-			});
-		}
-
-		if (!('loader' in config)) {
-			throw new AstroError({
-				...AstroErrorData.ContentCollectionMissingLoader,
-				message: AstroErrorData.ContentCollectionMissingLoader.message(importerFilename),
-			});
-		}
-
-		if (config.type && config.type !== CONTENT_LAYER_TYPE) {
-			throw new AstroError({
-				...AstroErrorData.ContentCollectionInvalidType,
-				message: AstroErrorData.ContentCollectionInvalidType.message(config.type, importerFilename),
-			});
-		}
-
-		if (
-			typeof config.loader === 'object' &&
-			typeof config.loader.load !== 'function' &&
-			('loadEntry' in config.loader || 'loadCollection' in config.loader)
-		) {
-			throw new AstroUserError(
-				`Live content collections must be defined in "src/live.config.ts" file. Check your collection definitions in "${importerFilename ?? 'your content config file'}" to ensure you are not using a live loader.`,
-			);
-		}
-		config.type = CONTENT_LAYER_TYPE;
-		return config;
+	TSchema extends BaseSchema,
+	TLoader extends LoaderConstraint<{ id: string }>,
+>(config: CollectionConfig<TSchema, TLoader>): CollectionConfig<TSchema, TLoader> {
+	const importerFilename = getImporterFilename();
+
+	if (importerFilename?.includes('live.config')) {
+		throw new AstroError({
+			...AstroErrorData.LiveContentConfigError,
+			message: AstroErrorData.LiveContentConfigError.message(
+				'Collections in a live config file must use `defineLiveCollection`.',
+				importerFilename,
+			),
+		});
 	}
+
+	if (!('loader' in config)) {
+		throw new AstroError({
+			...AstroErrorData.ContentCollectionMissingLoader,
+			message: AstroErrorData.ContentCollectionMissingLoader.message(importerFilename),
+		});
+	}
+
+	if (config.type && config.type !== CONTENT_LAYER_TYPE) {
+		throw new AstroError({
+			...AstroErrorData.ContentCollectionInvalidType,
+			message: AstroErrorData.ContentCollectionInvalidType.message(config.type, importerFilename),
+		});
+	}
+
+	if (
+		typeof config.loader === 'object' &&
+		typeof config.loader.load !== 'function' &&
+		('loadEntry' in config.loader || 'loadCollection' in config.loader)
+	) {
+		throw new AstroUserError(
+			`Live content collections must be defined in "src/live.config.ts" file. Check your collection definitions in "${importerFilename ?? 'your content config file'}" to ensure you are not using a live loader.`,
+		);
+	}
+	config.type = CONTENT_LAYER_TYPE;
+	return config;
+}
diff --git a/packages/astro/src/content/loaders/types.ts b/packages/astro/src/content/loaders/types.ts
index 8e37f9e5f470..8ad19043607d 100644
--- a/packages/astro/src/content/loaders/types.ts
+++ b/packages/astro/src/content/loaders/types.ts
@@ -50,26 +50,26 @@ export interface LoaderContext {
 }
 
 export type Loader<T extends ZodSchema = never> = {
-		/** Unique name of the loader, e.g. the npm package name */
-		name: string;
-		/** Do the actual loading of the data */
-		load: (context: LoaderContext) => Promise<void>;
-	} & ([T] extends [never]
-		?
-				| {
-						/** Optionally, define the schema of the data. Will be overridden by user-defined schema */
-						schema?: T;
-				  }
-				| {
-						getSchemaContext?: () => Promise<{
-							schema: ZodSchema;
-							types: string;
-						}>;
-				  }
-		: {
-				/** Optionally, define the schema of the data. Will be overridden by user-defined schema */
-				schema: T;
-			});
+	/** Unique name of the loader, e.g. the npm package name */
+	name: string;
+	/** Do the actual loading of the data */
+	load: (context: LoaderContext) => Promise<void>;
+} & ([T] extends [never]
+	?
+			| {
+					/** Optionally, define the schema of the data. Will be overridden by user-defined schema */
+					schema?: T;
+			  }
+			| {
+					getSchemaContext?: () => Promise<{
+						schema: ZodSchema;
+						types: string;
+					}>;
+			  }
+	: {
+			/** Optionally, define the schema of the data. Will be overridden by user-defined schema */
+			schema: T;
+		});
 
 export interface LoadEntryContext<TEntryFilter = never> {
 	filter: TEntryFilter extends never ? { id: string } : TEntryFilter;
diff --git a/packages/astro/src/content/types-generator.ts b/packages/astro/src/content/types-generator.ts
index b77dae648bf0..2204beca3a16 100644
--- a/packages/astro/src/content/types-generator.ts
+++ b/packages/astro/src/content/types-generator.ts
@@ -397,7 +397,7 @@ async function typeForCollection<T extends keyof ContentConfig['collections']>(
 	if (!result) {
 		return { type: 'any' };
 	}
-	const filename = `loaders/${collectionKey.slice(1,-1)}.ts`;
+	const filename = `loaders/${collectionKey.slice(1, -1)}.ts`;
 	return {
 		type: `import("./${filename}").Collection`,
 		injectedType: {

From 91a4d99e6f5248d9e29f7fab7ba60ee28c5065f9 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 13 Nov 2025 11:45:46 +0100
Subject: [PATCH 07/29] feat: error

---
 packages/astro/src/content/utils.ts | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/packages/astro/src/content/utils.ts b/packages/astro/src/content/utils.ts
index 11e582ff6356..1413a163baf9 100644
--- a/packages/astro/src/content/utils.ts
+++ b/packages/astro/src/content/utils.ts
@@ -61,7 +61,27 @@ const collectionConfigParser = z.union([
 			z.object({
 				name: z.string(),
 				load: z.function().args(z.custom<LoaderContext>()).returns(z.promise(z.void())),
-				schema: z.custom<ZodSchema>((v) => '_def' in v).optional(),
+				schema: z
+					.any()
+					.superRefine((v, ctx) => {
+						if (typeof v === 'function') {
+							ctx.addIssue({
+								code: z.ZodIssueCode.custom,
+								// TODO: should the message say to open an issue on the loader's repo?
+								message:
+									'Since Astro 6, a loader schema cannot be a function. Check the docs: TODO:',
+							});
+							return z.NEVER;
+						}
+						if (!('_def' in v)) {
+							ctx.addIssue({
+								code: z.ZodIssueCode.custom,
+								message: 'Invalid Zod schema',
+							});
+							return z.NEVER;
+						}
+					})
+					.optional(),
 				getSchemaContext: z
 					.function()
 					.returns(

From a0e3f43f8142b0b0f9c4f46335f6765477c3668f Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 13 Nov 2025 11:49:11 +0100
Subject: [PATCH 08/29] Discard changes to examples/blog/src/content.config.ts

---
 examples/blog/src/content.config.ts | 57 ++++++-----------------------
 1 file changed, 11 insertions(+), 46 deletions(-)

diff --git a/examples/blog/src/content.config.ts b/examples/blog/src/content.config.ts
index 64c9967b0781..ce37c7f6ff34 100644
--- a/examples/blog/src/content.config.ts
+++ b/examples/blog/src/content.config.ts
@@ -1,54 +1,19 @@
 import { defineCollection, z } from 'astro:content';
-import { defineContentLoader, glob } from 'astro/loaders';
-
-const test = (options: Parameters<typeof glob>[0]) =>
-	defineContentLoader({
-		name: 'test',
-		load: glob(options).load,
-		// schema: z.object({
-		// 	title: z.string(),
-		// 	description: z.string(),
-		// 	// Transform string to Date object
-		// 	pubDate: z.coerce.date(),
-		// 	updatedDate: z.coerce.date().optional(),
-		// 	heroImage: z.string().optional(),
-		// }),
-		getSchemaContext: async () => {
-			return {
-				schema: z.object({
-					title: z.string(),
-					description: z.string(),
-					// Transform string to Date object
-					pubDate: z.coerce.date(),
-					updatedDate: z.coerce.date().optional(),
-					heroImage: z.string().optional(),
-				}),
-				types: `import type { ImageMetadata } from "astro";
-
-export interface Collection {
-	title: string;
-	description: string;
-	pubDate: Date;
-	updateDate: Date | undefined;
-	heroImage: ImageMetadata | undefined;
-}`,
-			};
-		},
-	});
+import { glob } from 'astro/loaders';
 
 const blog = defineCollection({
 	// Load Markdown and MDX files in the `src/content/blog/` directory.
-	loader: test({ base: './src/content/blog', pattern: '**/*.{md,mdx}' }),
+	loader: glob({ base: './src/content/blog', pattern: '**/*.{md,mdx}' }),
 	// Type-check frontmatter using a schema
-	// schema: ({ image }) =>
-	// 	z.object({
-	// 		title: z.string(),
-	// 		description: z.string(),
-	// 		// Transform string to Date object
-	// 		pubDate: z.coerce.date(),
-	// 		updatedDate: z.coerce.date().optional(),
-	// 		heroImage: image().optional(),
-	// 	}),
+	schema: ({ image }) =>
+		z.object({
+			title: z.string(),
+			description: z.string(),
+			// Transform string to Date object
+			pubDate: z.coerce.date(),
+			updatedDate: z.coerce.date().optional(),
+			heroImage: image().optional(),
+		}),
 });
 
 export const collections = { blog };

From 652b78e8e8f5c4be1b48e7f8590349fea104873e Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 13 Nov 2025 12:02:05 +0100
Subject: [PATCH 09/29] feat: backward compat

---
 packages/astro/templates/content/types.d.ts | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/packages/astro/templates/content/types.d.ts b/packages/astro/templates/content/types.d.ts
index 9caa399bc7af..c89b7748a075 100644
--- a/packages/astro/templates/content/types.d.ts
+++ b/packages/astro/templates/content/types.d.ts
@@ -104,9 +104,12 @@ declare module 'astro:content' {
 	type InferEntrySchema<C extends keyof DataEntryMap> = import('astro/zod').infer<
 		ReturnTypeOrOriginal<Required<ContentConfig['collections'][C]>['schema']>
 	>;
-	type InferLoaderSchema<C extends keyof DataEntryMap> = import('astro/zod').infer<
-		Required<ContentConfig['collections'][C]>['loader']['schema']
-	>;
+	type InferLoaderSchema<
+		C extends keyof DataEntryMap,
+		L = Required<ContentConfig['collections'][C]>['loader'],
+	> = L extends { schema: import('astro/zod').ZodSchema }
+		? import('astro/zod').infer<Required<ContentConfig['collections'][C]>['loader']['schema']>
+		: any;
 
 	type DataEntryMap = {
 		// @@DATA_ENTRY_MAP@@

From 6e26dcd89c4516b7110d08760d830578ff58964b Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 13 Nov 2025 12:09:19 +0100
Subject: [PATCH 10/29] chore: remove unused dep

---
 packages/astro/package.json | 3 +--
 pnpm-lock.yaml              | 3 ---
 2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/packages/astro/package.json b/packages/astro/package.json
index 9d73588eda74..f1ca0143eee8 100644
--- a/packages/astro/package.json
+++ b/packages/astro/package.json
@@ -167,8 +167,7 @@
     "yargs-parser": "^21.1.1",
     "yocto-spinner": "^0.2.3",
     "zod": "^3.25.76",
-    "zod-to-json-schema": "^3.24.6",
-    "zod-to-ts": "^1.2.0"
+    "zod-to-json-schema": "^3.24.6"
   },
   "optionalDependencies": {
     "sharp": "^0.34.0"
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 00cf539bf36a..1d1155bbc7d6 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -643,9 +643,6 @@ importers:
       zod-to-json-schema:
         specifier: ^3.24.6
         version: 3.24.6(zod@3.25.76)
-      zod-to-ts:
-        specifier: ^1.2.0
-        version: 1.2.0(typescript@5.9.3)(zod@3.25.76)
     devDependencies:
       '@astrojs/check':
         specifier: workspace:*

From 67cb44f00eaa6ce47eded97586c5b4fb441a16f5 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 13 Nov 2025 14:03:23 +0100
Subject: [PATCH 11/29] fix: tests

---
 .../fixtures/content-layer/src/content.config.ts   | 14 +++++++++++---
 .../content-layer/src/loaders/post-loader.ts       | 14 +++++++++++---
 2 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/packages/astro/test/fixtures/content-layer/src/content.config.ts b/packages/astro/test/fixtures/content-layer/src/content.config.ts
index d3a173ff654d..981b732aca45 100644
--- a/packages/astro/test/fixtures/content-layer/src/content.config.ts
+++ b/packages/astro/test/fixtures/content-layer/src/content.config.ts
@@ -226,14 +226,22 @@ const increment = defineCollection({
 				rendered: await renderMarkdown(markdownContent)
 			});
 		},
-		// Example of a loader that returns an async schema function
-		schema: async () =>
-			z.object({
+		getSchemaContext: async () => {
+			return {
+				schema: z.object({
 				lastValue: z.number(),
 				lastUpdated: z.date(),
 				refreshContextData: z.record(z.unknown()).optional(),
 				slug: z.string().optional(),
 			}),
+			types: `export interface Collection {
+	lastValue: number;
+	lastUpdated: Date;
+	refreshContextData?: Record<string, unknown> | undefined;
+	slug?: string | undefined;
+}`
+			}
+		}
 	},
 });
 
diff --git a/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts b/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts
index b03c1442227e..55cc9d8d6185 100644
--- a/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts
+++ b/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts
@@ -31,15 +31,23 @@ export function loader(config:PostLoaderConfig): Loader {
 			}
 			meta.set('lastSynced', String(Date.now()));
 		},
-		schema: async () => {
+		getSchemaContext: async () => {
 			// Simulate a delay
 			await new Promise((resolve) => setTimeout(resolve, 1000));
-			return z.object({
+			return {
+				schema: z.object({
 				title: z.string(),
 				body: z.string(),
 				userId: z.number(),
 				id: z.number(),
-			});
+			}),
+			types: `export intreface Collection {
+	title: string;
+	body: string;
+	userId: number;
+	id: number;
+}`
+			}
 		}
 	};
 }

From b198c4c3a75896f5600dcf03ce6c1fe3ccf3dfdb Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 13 Nov 2025 14:33:00 +0100
Subject: [PATCH 12/29] test

---
 packages/astro/src/content/utils.ts           |  1 +
 packages/astro/test/astro-sync.test.js        | 43 ++++++++++++++++---
 .../astro.config.mjs                          |  3 ++
 .../package.json                              |  8 ++++
 .../src/content.config.ts                     | 14 ++++++
 pnpm-lock.yaml                                |  6 +++
 6 files changed, 68 insertions(+), 7 deletions(-)
 create mode 100644 packages/astro/test/fixtures/content-layer-loader-schema-function/astro.config.mjs
 create mode 100644 packages/astro/test/fixtures/content-layer-loader-schema-function/package.json
 create mode 100644 packages/astro/test/fixtures/content-layer-loader-schema-function/src/content.config.ts

diff --git a/packages/astro/src/content/utils.ts b/packages/astro/src/content/utils.ts
index 1413a163baf9..53a483b7b447 100644
--- a/packages/astro/src/content/utils.ts
+++ b/packages/astro/src/content/utils.ts
@@ -67,6 +67,7 @@ const collectionConfigParser = z.union([
 						if (typeof v === 'function') {
 							ctx.addIssue({
 								code: z.ZodIssueCode.custom,
+								// TODO: remove in Astro 7
 								// TODO: should the message say to open an issue on the loader's repo?
 								message:
 									'Since Astro 6, a loader schema cannot be a function. Check the docs: TODO:',
diff --git a/packages/astro/test/astro-sync.test.js b/packages/astro/test/astro-sync.test.js
index 43a00b355fa2..e06b29a6ad08 100644
--- a/packages/astro/test/astro-sync.test.js
+++ b/packages/astro/test/astro-sync.test.js
@@ -11,6 +11,8 @@ const createFixture = () => {
 	let astroFixture;
 	/** @type {Record<string, string>} */
 	const writtenFiles = {};
+	/** @type {Array<string>} */
+	const errorLogs = [];
 
 	/**
 	 * @param {string} path
@@ -50,13 +52,23 @@ const createFixture = () => {
 				},
 			};
 
-			await astroFixture.sync(
-				{ root: fileURLToPath(astroFixture.config.root) },
-				{
-					// @ts-ignore
-					fs: fsMock,
-				},
-			);
+			const originalError = console.error;
+			console.error = (message) => {
+				originalError(message);
+				errorLogs.push(message);
+			};
+
+			try {
+				await astroFixture.sync(
+					{ root: fileURLToPath(astroFixture.config.root) },
+					{
+						// @ts-ignore
+						fs: fsMock,
+					},
+				);
+			} finally {
+				console.error = originalError;
+			}
 		},
 		/** @param {string} path */
 		thenFileShouldExist(path) {
@@ -102,6 +114,16 @@ const createFixture = () => {
 				assert.fail(`${path} is not valid TypeScript. Error: ${error.message}`);
 			}
 		},
+		/**
+		 * @param {string} message
+		 */
+		thenErrorLogsInclude(message) {
+			if (errorLogs.length === 0) {
+				assert.fail('No error log');
+			}
+			const index = errorLogs.findIndex((log) => log.includes(message));
+			assert.equal(index !== -1, true, 'No error log found');
+		},
 	};
 };
 
@@ -170,6 +192,13 @@ describe('astro sync', () => {
 				'Types file does not include empty collection type',
 			);
 		});
+
+		it('fails when using a loader schema function', async () => {
+			await fixture.load('./fixtures/content-layer-loader-schema-function/');
+			fixture.clean();
+			await fixture.whenSyncing();
+			fixture.thenErrorLogsInclude('Since Astro 6, a loader schema cannot be a function.');
+		});
 	});
 
 	describe('astro:env', () => {
diff --git a/packages/astro/test/fixtures/content-layer-loader-schema-function/astro.config.mjs b/packages/astro/test/fixtures/content-layer-loader-schema-function/astro.config.mjs
new file mode 100644
index 000000000000..86dbfb924824
--- /dev/null
+++ b/packages/astro/test/fixtures/content-layer-loader-schema-function/astro.config.mjs
@@ -0,0 +1,3 @@
+import { defineConfig } from 'astro/config';
+
+export default defineConfig({});
diff --git a/packages/astro/test/fixtures/content-layer-loader-schema-function/package.json b/packages/astro/test/fixtures/content-layer-loader-schema-function/package.json
new file mode 100644
index 000000000000..4467e4797a5b
--- /dev/null
+++ b/packages/astro/test/fixtures/content-layer-loader-schema-function/package.json
@@ -0,0 +1,8 @@
+{
+  "name": "@test/content-layer-loader-schema-function",
+  "version": "0.0.0",
+  "private": true,
+  "dependencies": {
+    "astro": "workspace:*"
+  }
+}
diff --git a/packages/astro/test/fixtures/content-layer-loader-schema-function/src/content.config.ts b/packages/astro/test/fixtures/content-layer-loader-schema-function/src/content.config.ts
new file mode 100644
index 000000000000..f94f7cd93f53
--- /dev/null
+++ b/packages/astro/test/fixtures/content-layer-loader-schema-function/src/content.config.ts
@@ -0,0 +1,14 @@
+import { defineCollection, z } from 'astro:content';
+import { glob } from 'astro/loaders';
+
+const blog = defineCollection({
+	loader: {
+		name: 'test',
+		load: async () => {},
+		schema: () => z.object()
+	}
+});
+
+export const collections = {
+	blog,
+};
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 1d1155bbc7d6..1063f83e133f 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -2727,6 +2727,12 @@ importers:
         specifier: workspace:*
         version: link:../../..
 
+  packages/astro/test/fixtures/content-layer-loader-schema-function:
+    dependencies:
+      astro:
+        specifier: workspace:*
+        version: link:../../..
+
   packages/astro/test/fixtures/content-layer-markdoc:
     dependencies:
       '@astrojs/markdoc':

From 6f3daaf8932656e1346075b8d8d4255fb6b86def Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 13 Nov 2025 15:25:45 +0100
Subject: [PATCH 13/29] chore: todo

---
 packages/astro/src/content/utils.ts | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/packages/astro/src/content/utils.ts b/packages/astro/src/content/utils.ts
index 53a483b7b447..e189a4d38656 100644
--- a/packages/astro/src/content/utils.ts
+++ b/packages/astro/src/content/utils.ts
@@ -68,9 +68,8 @@ const collectionConfigParser = z.union([
 							ctx.addIssue({
 								code: z.ZodIssueCode.custom,
 								// TODO: remove in Astro 7
-								// TODO: should the message say to open an issue on the loader's repo?
 								message:
-									'Since Astro 6, a loader schema cannot be a function. Check the docs: TODO:',
+									'Since Astro 6, a loader schema cannot be a function. Report it to the loader author or check the docs: TODO:',
 							});
 							return z.NEVER;
 						}

From 77b47e0d85b1c54b4fb09734a2e1f4c547351d6a Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Thu, 13 Nov 2025 15:29:16 +0100
Subject: [PATCH 14/29] chore: changesets

---
 .changeset/deep-states-talk.md | 5 +++++
 .changeset/fresh-rocks-sing.md | 5 +++++
 .changeset/rare-apes-shout.md  | 5 +++++
 3 files changed, 15 insertions(+)
 create mode 100644 .changeset/deep-states-talk.md
 create mode 100644 .changeset/fresh-rocks-sing.md
 create mode 100644 .changeset/rare-apes-shout.md

diff --git a/.changeset/deep-states-talk.md b/.changeset/deep-states-talk.md
new file mode 100644
index 000000000000..e93537e1b484
--- /dev/null
+++ b/.changeset/deep-states-talk.md
@@ -0,0 +1,5 @@
+---
+'astro': major
+---
+
+Adds a new `defineContentLoader()` type helper (Loader API) - ([v6 upgrade guidance](https://deploy-preview-12322--astro-docs-2.netlify.app/en/guides/upgrade-to/v6/TODO:))
diff --git a/.changeset/fresh-rocks-sing.md b/.changeset/fresh-rocks-sing.md
new file mode 100644
index 000000000000..337b34b35b29
--- /dev/null
+++ b/.changeset/fresh-rocks-sing.md
@@ -0,0 +1,5 @@
+---
+'astro': major
+---
+
+Removes the ability for content loaders schemas to be functions (Loader API) - ([v6 upgrade guidance](https://deploy-preview-12322--astro-docs-2.netlify.app/en/guides/upgrade-to/v6/TODO:))
diff --git a/.changeset/rare-apes-shout.md b/.changeset/rare-apes-shout.md
new file mode 100644
index 000000000000..02540d414273
--- /dev/null
+++ b/.changeset/rare-apes-shout.md
@@ -0,0 +1,5 @@
+---
+'astro': major
+---
+
+Adds a new optional `getSchemaContext()` property (Loader API) - ([v6 upgrade guidance](https://deploy-preview-12322--astro-docs-2.netlify.app/en/guides/upgrade-to/v6/TODO:))

From b375c59107f644800a7e9516a1974e6af0908252 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 19 Nov 2025 08:44:56 +0100
Subject: [PATCH 15/29] Discard changes to
 packages/astro/src/content/loaders/glob.ts

---
 packages/astro/src/content/loaders/glob.ts | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/packages/astro/src/content/loaders/glob.ts b/packages/astro/src/content/loaders/glob.ts
index a94715104c50..99d0dbaca84f 100644
--- a/packages/astro/src/content/loaders/glob.ts
+++ b/packages/astro/src/content/loaders/glob.ts
@@ -8,7 +8,7 @@ import { glob as tinyglobby } from 'tinyglobby';
 import type { ContentEntryRenderFunction, ContentEntryType } from '../../types/public/content.js';
 import type { RenderedContent } from '../data-store.js';
 import { getContentEntryIdAndSlug, posixRelative } from '../utils.js';
-import { defineContentLoader } from './config.js';
+import type { Loader } from './types.js';
 
 interface GenerateIdOptions {
 	/** The path to the entry file, relative to the base directory. */
@@ -57,7 +57,7 @@ function checkPrefix(pattern: string | Array<string>, prefix: string) {
  * @param pattern A glob pattern to match files, relative to the content directory.
  */
 
-export function glob(globOptions: GlobOptions) {
+export function glob(globOptions: GlobOptions): Loader {
 	if (checkPrefix(globOptions.pattern, '../')) {
 		throw new Error(
 			'Glob patterns cannot start with `../`. Set the `base` option to a parent directory instead.',
@@ -73,7 +73,7 @@ export function glob(globOptions: GlobOptions) {
 
 	const fileToIdMap = new Map<string, string>();
 
-	return defineContentLoader({
+	return {
 		name: 'glob-loader',
 		load: async ({ config, logger, watcher, parseData, store, generateDigest, entryTypes }) => {
 			const renderFunctionByContentType = new WeakMap<
@@ -315,5 +315,5 @@ export function glob(globOptions: GlobOptions) {
 				}
 			});
 		},
-	});
+	};
 }

From c7fd7a6aedbb9547518bec8523c170381c803e26 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 19 Nov 2025 08:45:05 +0100
Subject: [PATCH 16/29] Discard changes to
 packages/astro/src/content/loaders/file.ts

---
 packages/astro/src/content/loaders/file.ts | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/packages/astro/src/content/loaders/file.ts b/packages/astro/src/content/loaders/file.ts
index 09b69f148884..c1b4b2a075a6 100644
--- a/packages/astro/src/content/loaders/file.ts
+++ b/packages/astro/src/content/loaders/file.ts
@@ -5,8 +5,7 @@ import toml from 'smol-toml';
 import { FileGlobNotSupported, FileParserNotFound } from '../../core/errors/errors-data.js';
 import { AstroError } from '../../core/errors/index.js';
 import { posixRelative } from '../utils.js';
-import { defineContentLoader } from './config.js';
-import type { LoaderContext } from './types.js';
+import type { Loader, LoaderContext } from './types.js';
 
 interface FileOptions {
 	/**
@@ -23,7 +22,7 @@ interface FileOptions {
  * @param fileName The path to the JSON file to load, relative to the content directory.
  * @param options Additional options for the file loader
  */
-export function file(fileName: string, options?: FileOptions) {
+export function file(fileName: string, options?: FileOptions): Loader {
 	if (fileName.includes('*')) {
 		throw new AstroError(FileGlobNotSupported);
 	}
@@ -103,7 +102,7 @@ export function file(fileName: string, options?: FileOptions) {
 		}
 	}
 
-	return defineContentLoader({
+	return {
 		name: 'file-loader',
 		load: async (context) => {
 			const { config, logger, watcher } = context;
@@ -126,5 +125,5 @@ export function file(fileName: string, options?: FileOptions) {
 				}
 			});
 		},
-	});
+	};
 }

From 09c6543a4ccf8ae2eb0a3940bf51c0d8c6672134 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 19 Nov 2025 08:48:29 +0100
Subject: [PATCH 17/29] Apply suggestion from @ascorbic

Co-authored-by: Matt Kane <m@mk.gg>
---
 .../test/fixtures/content-layer/src/loaders/post-loader.ts      | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts b/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts
index 55cc9d8d6185..ec8b3fd88b8e 100644
--- a/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts
+++ b/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts
@@ -41,7 +41,7 @@ export function loader(config:PostLoaderConfig): Loader {
 				userId: z.number(),
 				id: z.number(),
 			}),
-			types: `export intreface Collection {
+			types: /* ts */`export interface Collection {
 	title: string;
 	body: string;
 	userId: number;

From a5a64cc1bb5aac548661b6bd30bcc97bf2f892b3 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 19 Nov 2025 09:05:20 +0100
Subject: [PATCH 18/29] feedback

---
 packages/astro/src/content/types-generator.ts | 12 ++++++++----
 packages/astro/src/content/utils.ts           | 18 +++++++++---------
 2 files changed, 17 insertions(+), 13 deletions(-)

diff --git a/packages/astro/src/content/types-generator.ts b/packages/astro/src/content/types-generator.ts
index 2204beca3a16..f8d9028a44bb 100644
--- a/packages/astro/src/content/types-generator.ts
+++ b/packages/astro/src/content/types-generator.ts
@@ -513,10 +513,14 @@ async function writeContentFiles({
 
 			contentCollectionManifest.collections.push({
 				hasSchema: Boolean(
-					collectionConfig &&
-						(collectionConfig.schema ||
-							(typeof collectionConfig.loader !== 'function' &&
-								(collectionConfig.loader.schema || schemaContextResultCache.has(collectionKey)))),
+					// Is there a user provided schema or
+					collectionConfig?.schema ||
+						// Is it a loader object and
+						(typeof collectionConfig?.loader !== 'function' &&
+							// Is it a loader static schema or
+							(collectionConfig?.loader.schema ||
+								// is it a loader dynamic schema
+								schemaContextResultCache.has(collectionKey))),
 				),
 				name: key,
 			});
diff --git a/packages/astro/src/content/utils.ts b/packages/astro/src/content/utils.ts
index e189a4d38656..a5c1e6c44a89 100644
--- a/packages/astro/src/content/utils.ts
+++ b/packages/astro/src/content/utils.ts
@@ -63,17 +63,17 @@ const collectionConfigParser = z.union([
 				load: z.function().args(z.custom<LoaderContext>()).returns(z.promise(z.void())),
 				schema: z
 					.any()
-					.superRefine((v, ctx) => {
+					.transform((v) => {
 						if (typeof v === 'function') {
-							ctx.addIssue({
-								code: z.ZodIssueCode.custom,
-								// TODO: remove in Astro 7
-								message:
-									'Since Astro 6, a loader schema cannot be a function. Report it to the loader author or check the docs: TODO:',
-							});
-							return z.NEVER;
+							console.warn(
+								`Since Astro 6, a loader schema cannot be a function. It is ignored and will break in a future major. Report it to the loader author or check the docs: TODO:`,
+							);
+							return undefined;
 						}
-						if (!('_def' in v)) {
+						return v;
+					})
+					.superRefine((v, ctx) => {
+						if (v !== undefined && !('_def' in v)) {
 							ctx.addIssue({
 								code: z.ZodIssueCode.custom,
 								message: 'Invalid Zod schema',

From 5bb7411848b1f099c2197595a166ad98def76f4f Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Fri, 21 Nov 2025 09:10:25 +0100
Subject: [PATCH 19/29] Apply suggestion from @florian-lefebvre

---
 packages/astro/src/content/types-generator.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/astro/src/content/types-generator.ts b/packages/astro/src/content/types-generator.ts
index f8d9028a44bb..f9bb3e92adad 100644
--- a/packages/astro/src/content/types-generator.ts
+++ b/packages/astro/src/content/types-generator.ts
@@ -397,7 +397,7 @@ async function typeForCollection<T extends keyof ContentConfig['collections']>(
 	if (!result) {
 		return { type: 'any' };
 	}
-	const filename = `loaders/${collectionKey.slice(1, -1)}.ts`;
+	const filename = `loaders/${collectionKey.slice(1, -1)}.js`;
 	return {
 		type: `import("./${filename}").Collection`,
 		injectedType: {

From 8810bd33db3fefd85a3881af684c297ddd6064fb Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Fri, 21 Nov 2025 14:08:48 +0100
Subject: [PATCH 20/29] fix

---
 packages/astro/src/content/types-generator.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/packages/astro/src/content/types-generator.ts b/packages/astro/src/content/types-generator.ts
index 7fdd9561bf4f..f2c684fabb49 100644
--- a/packages/astro/src/content/types-generator.ts
+++ b/packages/astro/src/content/types-generator.ts
@@ -397,11 +397,11 @@ async function typeForCollection<T extends keyof ContentConfig['collections']>(
 	if (!result) {
 		return { type: 'any' };
 	}
-	const filename = `loaders/${collectionKey.slice(1, -1)}.js`;
+	const base = `loaders/${collectionKey.slice(1, -1)}`;
 	return {
-		type: `import("./${filename}").Collection`,
+		type: `import("./${base}.js").Collection`,
 		injectedType: {
-			filename,
+			filename: `${base}.ts`,
 			content: result.types,
 		},
 	};

From c409b14e638a460848e9807f3bbcc309d28ef999 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 3 Dec 2025 11:17:28 +0100
Subject: [PATCH 21/29] fix: test

---
 packages/astro/test/astro-sync.test.js | 20 ++++++++++----------
 1 file changed, 10 insertions(+), 10 deletions(-)

diff --git a/packages/astro/test/astro-sync.test.js b/packages/astro/test/astro-sync.test.js
index e06b29a6ad08..45c59f2f7840 100644
--- a/packages/astro/test/astro-sync.test.js
+++ b/packages/astro/test/astro-sync.test.js
@@ -12,7 +12,7 @@ const createFixture = () => {
 	/** @type {Record<string, string>} */
 	const writtenFiles = {};
 	/** @type {Array<string>} */
-	const errorLogs = [];
+	const warnLogs = [];
 
 	/**
 	 * @param {string} path
@@ -52,10 +52,10 @@ const createFixture = () => {
 				},
 			};
 
-			const originalError = console.error;
-			console.error = (message) => {
-				originalError(message);
-				errorLogs.push(message);
+			const originalWarn = console.warn;
+			console.warn = (message) => {
+				originalWarn(message);
+				warnLogs.push(message);
 			};
 
 			try {
@@ -67,7 +67,7 @@ const createFixture = () => {
 					},
 				);
 			} finally {
-				console.error = originalError;
+				console.error = originalWarn;
 			}
 		},
 		/** @param {string} path */
@@ -117,11 +117,11 @@ const createFixture = () => {
 		/**
 		 * @param {string} message
 		 */
-		thenErrorLogsInclude(message) {
-			if (errorLogs.length === 0) {
+		thenWarnLogsInclude(message) {
+			if (warnLogs.length === 0) {
 				assert.fail('No error log');
 			}
-			const index = errorLogs.findIndex((log) => log.includes(message));
+			const index = warnLogs.findIndex((log) => log.includes(message));
 			assert.equal(index !== -1, true, 'No error log found');
 		},
 	};
@@ -197,7 +197,7 @@ describe('astro sync', () => {
 			await fixture.load('./fixtures/content-layer-loader-schema-function/');
 			fixture.clean();
 			await fixture.whenSyncing();
-			fixture.thenErrorLogsInclude('Since Astro 6, a loader schema cannot be a function.');
+			fixture.thenWarnLogsInclude('Since Astro 6, a loader schema cannot be a function.');
 		});
 	});
 

From d2c3fd8c81699b0270b913c69fde05fa4b8dd3f3 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 3 Dec 2025 11:22:52 +0100
Subject: [PATCH 22/29] feedback

---
 .changeset/deep-states-talk.md               |  2 +-
 .changeset/fresh-rocks-sing.md               |  2 +-
 .changeset/rare-apes-shout.md                |  5 ----
 packages/astro/src/content/loaders/config.ts |  6 ----
 packages/astro/src/content/loaders/index.ts  |  1 -
 packages/astro/src/content/loaders/types.ts  | 29 +++++++++-----------
 6 files changed, 15 insertions(+), 30 deletions(-)
 delete mode 100644 .changeset/rare-apes-shout.md
 delete mode 100644 packages/astro/src/content/loaders/config.ts

diff --git a/.changeset/deep-states-talk.md b/.changeset/deep-states-talk.md
index e93537e1b484..ee4760061141 100644
--- a/.changeset/deep-states-talk.md
+++ b/.changeset/deep-states-talk.md
@@ -2,4 +2,4 @@
 'astro': major
 ---
 
-Adds a new `defineContentLoader()` type helper (Loader API) - ([v6 upgrade guidance](https://deploy-preview-12322--astro-docs-2.netlify.app/en/guides/upgrade-to/v6/TODO:))
+Updates how schema types are inferred for content loaders with schemas (Loader API) - ([v6 upgrade guidance](https://deploy-preview-12322--astro-docs-2.netlify.app/en/guides/upgrade-to/v6/TODO:))
diff --git a/.changeset/fresh-rocks-sing.md b/.changeset/fresh-rocks-sing.md
index 337b34b35b29..347a174c152a 100644
--- a/.changeset/fresh-rocks-sing.md
+++ b/.changeset/fresh-rocks-sing.md
@@ -2,4 +2,4 @@
 'astro': major
 ---
 
-Removes the ability for content loaders schemas to be functions (Loader API) - ([v6 upgrade guidance](https://deploy-preview-12322--astro-docs-2.netlify.app/en/guides/upgrade-to/v6/TODO:))
+Removes the ability for content loaders schemas to be functions and adds a new equivalent `getSchemaContext()` property (Loader API) - ([v6 upgrade guidance](https://deploy-preview-12322--astro-docs-2.netlify.app/en/guides/upgrade-to/v6/TODO:))
diff --git a/.changeset/rare-apes-shout.md b/.changeset/rare-apes-shout.md
deleted file mode 100644
index 02540d414273..000000000000
--- a/.changeset/rare-apes-shout.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-'astro': major
----
-
-Adds a new optional `getSchemaContext()` property (Loader API) - ([v6 upgrade guidance](https://deploy-preview-12322--astro-docs-2.netlify.app/en/guides/upgrade-to/v6/TODO:))
diff --git a/packages/astro/src/content/loaders/config.ts b/packages/astro/src/content/loaders/config.ts
deleted file mode 100644
index 0616d7beb9ca..000000000000
--- a/packages/astro/src/content/loaders/config.ts
+++ /dev/null
@@ -1,6 +0,0 @@
-import type { ZodSchema } from 'zod';
-import type { Loader } from './types.js';
-
-export function defineContentLoader<T extends ZodSchema | never = never>(loader: Loader<T>) {
-	return loader;
-}
diff --git a/packages/astro/src/content/loaders/index.ts b/packages/astro/src/content/loaders/index.ts
index 51a2de9fb748..30b4bfbe5334 100644
--- a/packages/astro/src/content/loaders/index.ts
+++ b/packages/astro/src/content/loaders/index.ts
@@ -1,4 +1,3 @@
-export { defineContentLoader } from './config.js';
 export { file } from './file.js';
 export { glob } from './glob.js';
 export * from './types.js';
diff --git a/packages/astro/src/content/loaders/types.ts b/packages/astro/src/content/loaders/types.ts
index 8ad19043607d..7fbb30f80988 100644
--- a/packages/astro/src/content/loaders/types.ts
+++ b/packages/astro/src/content/loaders/types.ts
@@ -49,27 +49,24 @@ export interface LoaderContext {
 	entryTypes: Map<string, ContentEntryType>;
 }
 
-export type Loader<T extends ZodSchema = never> = {
+export type Loader = {
 	/** Unique name of the loader, e.g. the npm package name */
 	name: string;
 	/** Do the actual loading of the data */
 	load: (context: LoaderContext) => Promise<void>;
-} & ([T] extends [never]
-	?
-			| {
-					/** Optionally, define the schema of the data. Will be overridden by user-defined schema */
-					schema?: T;
-			  }
-			| {
-					getSchemaContext?: () => Promise<{
-						schema: ZodSchema;
-						types: string;
-					}>;
-			  }
-	: {
+} & (
+	| {
 			/** Optionally, define the schema of the data. Will be overridden by user-defined schema */
-			schema: T;
-		});
+			schema?: ZodSchema;
+	  }
+	| {
+			/** Optionally, provide a function to dynamically provide a schema. Will be overridden by user-defined schema */
+			getSchemaContext?: () => Promise<{
+				schema: ZodSchema;
+				types: string;
+			}>;
+	  }
+);
 
 export interface LoadEntryContext<TEntryFilter = never> {
 	filter: TEntryFilter extends never ? { id: string } : TEntryFilter;

From d9b14c4a99128f5847b9110ee8ffa2001c6814d4 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 3 Dec 2025 11:32:41 +0100
Subject: [PATCH 23/29] Apply suggestion from @florian-lefebvre

---
 .../astro/test/fixtures/content-layer/src/content.config.ts     | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/astro/test/fixtures/content-layer/src/content.config.ts b/packages/astro/test/fixtures/content-layer/src/content.config.ts
index 981b732aca45..fa3c73ec7558 100644
--- a/packages/astro/test/fixtures/content-layer/src/content.config.ts
+++ b/packages/astro/test/fixtures/content-layer/src/content.config.ts
@@ -234,7 +234,7 @@ const increment = defineCollection({
 				refreshContextData: z.record(z.unknown()).optional(),
 				slug: z.string().optional(),
 			}),
-			types: `export interface Collection {
+			types: /* ts */`export interface Collection {
 	lastValue: number;
 	lastUpdated: Date;
 	refreshContextData?: Record<string, unknown> | undefined;

From 9057916ec74681cdd1bc514e4509e4437c9e859f Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 3 Dec 2025 11:47:45 +0100
Subject: [PATCH 24/29] feat: rename getSchemaContext to createSchema

---
 .changeset/fresh-rocks-sing.md                 |  2 +-
 packages/astro/src/content/content-layer.ts    |  4 ++--
 packages/astro/src/content/loaders/types.ts    |  2 +-
 packages/astro/src/content/types-generator.ts  | 18 +++++++++---------
 packages/astro/src/content/utils.ts            |  2 +-
 .../content-layer/src/content.config.ts        |  2 +-
 .../content-layer/src/loaders/post-loader.ts   |  2 +-
 7 files changed, 16 insertions(+), 16 deletions(-)

diff --git a/.changeset/fresh-rocks-sing.md b/.changeset/fresh-rocks-sing.md
index 347a174c152a..6920ff2a729c 100644
--- a/.changeset/fresh-rocks-sing.md
+++ b/.changeset/fresh-rocks-sing.md
@@ -2,4 +2,4 @@
 'astro': major
 ---
 
-Removes the ability for content loaders schemas to be functions and adds a new equivalent `getSchemaContext()` property (Loader API) - ([v6 upgrade guidance](https://deploy-preview-12322--astro-docs-2.netlify.app/en/guides/upgrade-to/v6/TODO:))
+Removes the ability for content loaders schemas to be functions and adds a new equivalent `createSchema()` property (Loader API) - ([v6 upgrade guidance](https://deploy-preview-12322--astro-docs-2.netlify.app/en/guides/upgrade-to/v6/TODO:))
diff --git a/packages/astro/src/content/content-layer.ts b/packages/astro/src/content/content-layer.ts
index f55fbbe46f92..583f104e8e4c 100644
--- a/packages/astro/src/content/content-layer.ts
+++ b/packages/astro/src/content/content-layer.ts
@@ -253,8 +253,8 @@ class ContentLayer {
 
 				if (!schema && typeof collection.loader === 'object') {
 					schema = collection.loader.schema;
-					if (!schema && collection.loader.getSchemaContext) {
-						({ schema } = await collection.loader.getSchemaContext());
+					if (!schema && collection.loader.createSchema) {
+						({ schema } = await collection.loader.createSchema());
 					}
 				}
 
diff --git a/packages/astro/src/content/loaders/types.ts b/packages/astro/src/content/loaders/types.ts
index 7fbb30f80988..8b7449751f66 100644
--- a/packages/astro/src/content/loaders/types.ts
+++ b/packages/astro/src/content/loaders/types.ts
@@ -61,7 +61,7 @@ export type Loader = {
 	  }
 	| {
 			/** Optionally, provide a function to dynamically provide a schema. Will be overridden by user-defined schema */
-			getSchemaContext?: () => Promise<{
+			createSchema?: () => Promise<{
 				schema: ZodSchema;
 				types: string;
 			}>;
diff --git a/packages/astro/src/content/types-generator.ts b/packages/astro/src/content/types-generator.ts
index f2c684fabb49..2b9207804d71 100644
--- a/packages/astro/src/content/types-generator.ts
+++ b/packages/astro/src/content/types-generator.ts
@@ -343,13 +343,13 @@ function normalizeConfigPath(from: string, to: string) {
 	return `"${isRelativePath(configPath) ? '' : './'}${normalizedPath}"` as const;
 }
 
-const schemaContextResultCache = new Map<string, { schema: ZodSchema; types: string }>();
+const createSchemaResultCache = new Map<string, { schema: ZodSchema; types: string }>();
 
-async function getSchemaContextResult<T extends keyof ContentConfig['collections']>(
+async function getCreateSchemaResult<T extends keyof ContentConfig['collections']>(
 	collection: ContentConfig['collections'][T],
 	collectionKey: T,
 ) {
-	const cached = schemaContextResultCache.get(collectionKey);
+	const cached = createSchemaResultCache.get(collectionKey);
 	if (cached) {
 		return cached;
 	}
@@ -358,10 +358,10 @@ async function getSchemaContextResult<T extends keyof ContentConfig['collections
 		collection?.type === CONTENT_LAYER_TYPE &&
 		typeof collection.loader === 'object' &&
 		!collection.loader.schema &&
-		collection.loader.getSchemaContext
+		collection.loader.createSchema
 	) {
-		const result = await collection.loader.getSchemaContext();
-		schemaContextResultCache.set(collectionKey, result);
+		const result = await collection.loader.createSchema();
+		createSchemaResultCache.set(collectionKey, result);
 		return result;
 	}
 }
@@ -376,7 +376,7 @@ async function getContentLayerSchema<T extends keyof ContentConfig['collections'
 	if (collection.loader.schema) {
 		return collection.loader.schema;
 	}
-	const result = await getSchemaContextResult(collection, collectionKey);
+	const result = await getCreateSchemaResult(collection, collectionKey);
 	return result?.schema;
 }
 
@@ -393,7 +393,7 @@ async function typeForCollection<T extends keyof ContentConfig['collections']>(
 	if (collection.loader.schema) {
 		return { type: `InferLoaderSchema<${collectionKey}>` };
 	}
-	const result = await getSchemaContextResult(collection, collectionKey);
+	const result = await getCreateSchemaResult(collection, collectionKey);
 	if (!result) {
 		return { type: 'any' };
 	}
@@ -520,7 +520,7 @@ async function writeContentFiles({
 							// Is it a loader static schema or
 							(collectionConfig?.loader.schema ||
 								// is it a loader dynamic schema
-								schemaContextResultCache.has(collectionKey))),
+								createSchemaResultCache.has(collectionKey))),
 				),
 				name: key,
 			});
diff --git a/packages/astro/src/content/utils.ts b/packages/astro/src/content/utils.ts
index 1bc9800c6956..a05fd4b7042c 100644
--- a/packages/astro/src/content/utils.ts
+++ b/packages/astro/src/content/utils.ts
@@ -82,7 +82,7 @@ const collectionConfigParser = z.union([
 						}
 					})
 					.optional(),
-				getSchemaContext: z
+				createSchema: z
 					.function()
 					.returns(
 						z.promise(
diff --git a/packages/astro/test/fixtures/content-layer/src/content.config.ts b/packages/astro/test/fixtures/content-layer/src/content.config.ts
index fa3c73ec7558..ed51a7f07e54 100644
--- a/packages/astro/test/fixtures/content-layer/src/content.config.ts
+++ b/packages/astro/test/fixtures/content-layer/src/content.config.ts
@@ -226,7 +226,7 @@ const increment = defineCollection({
 				rendered: await renderMarkdown(markdownContent)
 			});
 		},
-		getSchemaContext: async () => {
+		createSchema: async () => {
 			return {
 				schema: z.object({
 				lastValue: z.number(),
diff --git a/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts b/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts
index ec8b3fd88b8e..f0b7a0a95a40 100644
--- a/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts
+++ b/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts
@@ -31,7 +31,7 @@ export function loader(config:PostLoaderConfig): Loader {
 			}
 			meta.set('lastSynced', String(Date.now()));
 		},
-		getSchemaContext: async () => {
+		createSchema: async () => {
 			// Simulate a delay
 			await new Promise((resolve) => setTimeout(resolve, 1000));
 			return {

From ad72298654555a84f569fcd2ba436e4c46b64761 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 3 Dec 2025 14:33:39 +0100
Subject: [PATCH 25/29] Apply suggestions from code review

---
 packages/astro/src/content/types-generator.ts                   | 2 +-
 .../astro/test/fixtures/content-layer/src/content.config.ts     | 2 +-
 .../test/fixtures/content-layer/src/loaders/post-loader.ts      | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/packages/astro/src/content/types-generator.ts b/packages/astro/src/content/types-generator.ts
index 2b9207804d71..bfe934f20cda 100644
--- a/packages/astro/src/content/types-generator.ts
+++ b/packages/astro/src/content/types-generator.ts
@@ -399,7 +399,7 @@ async function typeForCollection<T extends keyof ContentConfig['collections']>(
 	}
 	const base = `loaders/${collectionKey.slice(1, -1)}`;
 	return {
-		type: `import("./${base}.js").Collection`,
+		type: `import("./${base}.js").Entry`,
 		injectedType: {
 			filename: `${base}.ts`,
 			content: result.types,
diff --git a/packages/astro/test/fixtures/content-layer/src/content.config.ts b/packages/astro/test/fixtures/content-layer/src/content.config.ts
index ed51a7f07e54..121f9b274870 100644
--- a/packages/astro/test/fixtures/content-layer/src/content.config.ts
+++ b/packages/astro/test/fixtures/content-layer/src/content.config.ts
@@ -234,7 +234,7 @@ const increment = defineCollection({
 				refreshContextData: z.record(z.unknown()).optional(),
 				slug: z.string().optional(),
 			}),
-			types: /* ts */`export interface Collection {
+			types: /* ts */`export interface Entry {
 	lastValue: number;
 	lastUpdated: Date;
 	refreshContextData?: Record<string, unknown> | undefined;
diff --git a/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts b/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts
index f0b7a0a95a40..d68a2a3f9c83 100644
--- a/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts
+++ b/packages/astro/test/fixtures/content-layer/src/loaders/post-loader.ts
@@ -41,7 +41,7 @@ export function loader(config:PostLoaderConfig): Loader {
 				userId: z.number(),
 				id: z.number(),
 			}),
-			types: /* ts */`export interface Collection {
+			types: /* ts */`export interface Entry {
 	title: string;
 	body: string;
 	userId: number;

From 1e906b2e28a189bc502085e072e017700e197c73 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 3 Dec 2025 17:14:01 +0100
Subject: [PATCH 26/29] Update packages/astro/src/content/utils.ts

Co-authored-by: Sarah Rainsberger <5098874+sarah11918@users.noreply.github.com>
---
 packages/astro/src/content/utils.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/astro/src/content/utils.ts b/packages/astro/src/content/utils.ts
index a05fd4b7042c..1244f8772d4c 100644
--- a/packages/astro/src/content/utils.ts
+++ b/packages/astro/src/content/utils.ts
@@ -66,7 +66,7 @@ const collectionConfigParser = z.union([
 					.transform((v) => {
 						if (typeof v === 'function') {
 							console.warn(
-								`Since Astro 6, a loader schema cannot be a function. It is ignored and will break in a future major. Report it to the loader author or check the docs: TODO:`,
+								`Your loader's schema is defined using a function. This is no longer supported and the schema will be ignored. Please update your loader to use the `createSchema()` utility instead, or report this to the loader author. In a future major version, this will cause the loader to break entirely.`,
 							);
 							return undefined;
 						}

From 591eeb84ea02999e928452a478012c317b38f049 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 3 Dec 2025 17:14:22 +0100
Subject: [PATCH 27/29] Update .changeset/fresh-rocks-sing.md

Co-authored-by: Sarah Rainsberger <5098874+sarah11918@users.noreply.github.com>
---
 .changeset/fresh-rocks-sing.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/.changeset/fresh-rocks-sing.md b/.changeset/fresh-rocks-sing.md
index 6920ff2a729c..072b42123a22 100644
--- a/.changeset/fresh-rocks-sing.md
+++ b/.changeset/fresh-rocks-sing.md
@@ -2,4 +2,4 @@
 'astro': major
 ---
 
-Removes the ability for content loaders schemas to be functions and adds a new equivalent `createSchema()` property (Loader API) - ([v6 upgrade guidance](https://deploy-preview-12322--astro-docs-2.netlify.app/en/guides/upgrade-to/v6/TODO:))
+Removes the option to define dynamic schemas in content loaders as functions and adds a new equivalent `createSchema()` property (Loader API) - ([v6 upgrade guidance](https://deploy-preview-12322--astro-docs-2.netlify.app/en/guides/upgrade-to/v6/TODO:))

From 0c1b5589cbbc94c16408e30e81f1b0859ce5559b Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 3 Dec 2025 17:15:15 +0100
Subject: [PATCH 28/29] Apply suggestion from @florian-lefebvre

---
 packages/astro/test/astro-sync.test.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/astro/test/astro-sync.test.js b/packages/astro/test/astro-sync.test.js
index 45c59f2f7840..56e4a766c2b8 100644
--- a/packages/astro/test/astro-sync.test.js
+++ b/packages/astro/test/astro-sync.test.js
@@ -197,7 +197,7 @@ describe('astro sync', () => {
 			await fixture.load('./fixtures/content-layer-loader-schema-function/');
 			fixture.clean();
 			await fixture.whenSyncing();
-			fixture.thenWarnLogsInclude('Since Astro 6, a loader schema cannot be a function.');
+			fixture.thenWarnLogsInclude("Your loader's schema is defined using a function.");
 		});
 	});
 

From 551dea964bf9c54989ebb19a23a8782e8fa04591 Mon Sep 17 00:00:00 2001
From: Florian Lefebvre <contact@florian-lefebvre.dev>
Date: Wed, 3 Dec 2025 17:33:52 +0100
Subject: [PATCH 29/29] Apply suggestion from @florian-lefebvre

---
 packages/astro/src/content/utils.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/astro/src/content/utils.ts b/packages/astro/src/content/utils.ts
index 1244f8772d4c..023b0b495e43 100644
--- a/packages/astro/src/content/utils.ts
+++ b/packages/astro/src/content/utils.ts
@@ -66,7 +66,7 @@ const collectionConfigParser = z.union([
 					.transform((v) => {
 						if (typeof v === 'function') {
 							console.warn(
-								`Your loader's schema is defined using a function. This is no longer supported and the schema will be ignored. Please update your loader to use the `createSchema()` utility instead, or report this to the loader author. In a future major version, this will cause the loader to break entirely.`,
+								`Your loader's schema is defined using a function. This is no longer supported and the schema will be ignored. Please update your loader to use the \`createSchema()\` utility instead, or report this to the loader author. In a future major version, this will cause the loader to break entirely.`,
 							);
 							return undefined;
 						}