diff --git a/src/vs/workbench/contrib/chat/browser/actions/chatPluginActions.ts b/src/vs/workbench/contrib/chat/browser/actions/chatPluginActions.ts
index 734bc935c0e41..88ff9acfacba4 100644
--- a/src/vs/workbench/contrib/chat/browser/actions/chatPluginActions.ts
+++ b/src/vs/workbench/contrib/chat/browser/actions/chatPluginActions.ts
@@ -60,11 +60,11 @@ class InstallFromSourceAction extends Action2 {
 		});
 	}
 
-	async run(accessor: ServicesAccessor): Promise<void> {
+	async run(accessor: ServicesAccessor, args?: { source?: string; sha?: string }): Promise<void> {
 		const quickInputService = accessor.get(IQuickInputService);
 		const pluginInstallService = accessor.get(IPluginInstallService);
 
-		const source = await quickInputService.input({
+		const source = args?.source ?? await quickInputService.input({
 			placeHolder: localize('pluginSourcePlaceholder', "owner/repo or git clone URL"),
 			prompt: localize('pluginSourcePrompt', "Enter a GitHub repository or git URL to install a plugin from"),
 		});
@@ -73,7 +73,7 @@ class InstallFromSourceAction extends Action2 {
 			return;
 		}
 
-		await pluginInstallService.installPluginFromSource(source.trim());
+		await pluginInstallService.installPluginFromSource(source.trim(), args?.sha);
 	}
 }
 
diff --git a/src/vs/workbench/contrib/chat/browser/pluginInstallService.ts b/src/vs/workbench/contrib/chat/browser/pluginInstallService.ts
index 723f6087915cc..d8e84ecf1b92a 100644
--- a/src/vs/workbench/contrib/chat/browser/pluginInstallService.ts
+++ b/src/vs/workbench/contrib/chat/browser/pluginInstallService.ts
@@ -55,7 +55,7 @@ export class PluginInstallService implements IPluginInstallService {
 		return this._installGitPlugin(plugin);
 	}
 
-	async installPluginFromSource(source: string): Promise<void> {
+	async installPluginFromSource(source: string, sha?: string): Promise<void> {
 		const reference = parseMarketplaceReference(source);
 		if (!reference) {
 			this._notificationService.notify({
@@ -75,8 +75,8 @@ export class PluginInstallService implements IPluginInstallService {
 
 		// Build a source descriptor for the git clone.
 		const sourceDescriptor = reference.kind === MarketplaceReferenceKind.GitHubShorthand
-			? { kind: PluginSourceKind.GitHub as const, repo: reference.githubRepo! }
-			: { kind: PluginSourceKind.GitUrl as const, url: reference.cloneUrl };
+			? { kind: PluginSourceKind.GitHub as const, repo: reference.githubRepo!, sha }
+			: { kind: PluginSourceKind.GitUrl as const, url: reference.cloneUrl, sha };
 
 		// Build a temporary plugin object for the trust gate and clone step.
 		const tempPlugin: IMarketplacePlugin = {
diff --git a/src/vs/workbench/contrib/chat/common/plugins/pluginInstallService.ts b/src/vs/workbench/contrib/chat/common/plugins/pluginInstallService.ts
index 22bddcd54a56d..750b903c06dd4 100644
--- a/src/vs/workbench/contrib/chat/common/plugins/pluginInstallService.ts
+++ b/src/vs/workbench/contrib/chat/common/plugins/pluginInstallService.ts
@@ -47,8 +47,11 @@ export interface IPluginInstallService {
 	 * GitHub shorthand (`owner/repo`) or a full git clone URL. Clones the
 	 * repository, reads marketplace metadata to discover plugins, and
 	 * registers the selected plugin.
+	 *
+	 * @param source A GitHub shorthand (`owner/repo`) or full git clone URL.
+	 * @param sha Optional commit SHA to pin the installation to a specific revision.
 	 */
-	installPluginFromSource(source: string): Promise<void>;
+	installPluginFromSource(source: string, sha?: string): Promise<void>;
 
 	/**
 	 * Pulls the latest changes for an already-cloned marketplace repository.