code · pull · Feb 19, 2026 · Feb 19, 2026
diff --git a/.changeset/clear-route-cache-content.md b/.changeset/clear-route-cache-content.md
@@ -0,0 +1,5 @@
+---
+"astro": patch
+---
+
+Clear the route cache on content changes so slug pages reflect updated data during dev.
diff --git a/packages/astro/src/content/vite-plugin-content-virtual-mod.ts b/packages/astro/src/content/vite-plugin-content-virtual-mod.ts
@@ -39,6 +39,9 @@ function invalidateDataStore(viteServer: ViteDevServer) {
 		// Pass `true` to mark this as HMR invalidation so Vite drops cached SSR results.
 		environment.moduleGraph.invalidateModule(module, undefined, timestamp, true);
 	}
+	// Signal the SSR runner to clear its route cache so that getStaticPaths()
+	// is re-evaluated with the updated content collection data.
+	environment.hot.send('astro:content-changed', {});
 	viteServer.environments.client.hot.send({
 		type: 'full-reload',
 		path: '*',

diff --git a/packages/astro/src/core/app/entrypoints/virtual/dev.ts b/packages/astro/src/core/app/entrypoints/virtual/dev.ts
@@ -26,6 +26,13 @@ export const createApp: CreateApp = ({ streaming } = {}) => {
 				logger.error('router', `Failed to update routes via HMR:\n ${e}`);
 			}
 		});
+
+		// Listen for content collection changes via HMR.
+		// Clear the route cache so getStaticPaths() is re-evaluated with fresh data.
+		import.meta.hot.on('astro:content-changed', () => {
+			if (!currentDevApp) return;
+			currentDevApp.pipeline.routeCache.clearAll();
+		});
 	}
 
 	return currentDevApp;

diff --git a/packages/astro/src/vite-plugin-app/app.ts b/packages/astro/src/vite-plugin-app/app.ts
@@ -61,6 +61,14 @@ export class AstroServerApp extends BaseApp<RunnablePipeline> {
 		ensure404Route(this.manifestData);
 	}
 
+	/**
+	 * Clears the route cache so that getStaticPaths() is re-evaluated.
+	 * Called via HMR when content collection data changes.
+	 */
+	clearRouteCache(): void {
+		this.pipeline.clearRouteCache();
+	}
+
 	async devMatch(pathname: string): Promise<DevMatch | undefined> {
 		const matchedRoute = await matchRoute(
 			pathname,

diff --git a/packages/astro/src/vite-plugin-app/createAstroServerApp.ts b/packages/astro/src/vite-plugin-app/createAstroServerApp.ts
@@ -71,6 +71,13 @@ export default async function createAstroServerApp(
 				actualLogger.error('router', `Failed to update routes via HMR:\n ${e}`);
 			}
 		});
+
+		// Listen for content collection changes via HMR.
+		// Clear the route cache so getStaticPaths() is re-evaluated with fresh data.
+		import.meta.hot.on('astro:content-changed', () => {
+			app.clearRouteCache();
+			actualLogger.debug('router', 'Route cache cleared due to content change');
+		});
 	}
 
 	return {

diff --git a/packages/astro/test/fixtures/hmr-markdown/src/pages/blog/[slug].astro b/packages/astro/test/fixtures/hmr-markdown/src/pages/blog/[slug].astro
@@ -0,0 +1,24 @@
+---
+import { getCollection, render } from 'astro:content';
+
+export async function getStaticPaths() {
+	const posts = await getCollection('blog');
+	return posts.map((post) => ({ params: { slug: post.id }, props: { post } }));
+}
+
+const { post } = Astro.props;
+
+const { Content } = await render(post);
+---
+
+<html>
+	<head>
+		<title>{post.data.title}</title>
+	</head>
+	<body>
+		<h1>{post.data.title}</h1>
+		<div id="post-body">
+			<Content />
+		</div>
+	</body>
+</html>
diff --git a/packages/astro/test/hmr-markdown.test.js b/packages/astro/test/hmr-markdown.test.js
@@ -32,13 +32,23 @@ describe('HMR: Markdown updates', () => {
 			let html = await response.text();
 			assert.ok(html.includes('Original content'));
 
+			response = await fixture.fetch('/blog/post');
+			assert.equal(response.status, 200);
+			html = await response.text();
+			assert.ok(html.includes('Original content'));
+
 			await fixture.editFile(markdownPath, UPDATED_CONTENT);
 			await fixture.onNextDataStoreChange();
 
 			response = await fixture.fetch('/');
 			assert.equal(response.status, 200);
 			html = await response.text();
 			assert.ok(html.includes('Updated content'));
+
+			response = await fixture.fetch('/blog/post');
+			assert.equal(response.status, 200);
+			html = await response.text();
+			assert.ok(html.includes('Updated content'));
 		},
 	);
 });