From a05df0a81a99d4c87023e98b294c48fdd9878833 Mon Sep 17 00:00:00 2001
From: Pascal <admin@serveurperso.com>
Date: Wed, 15 Jul 2026 13:39:21 +0200
Subject: [PATCH] ui: fix thinking menu never appearing in single-model mode
 (#25637)

In MODEL mode, modelPropsCache is never populated: fetchModelProps
call sites are gated on router-only state (isRouterMode checks,
routerModels always empty), so supportsThinking always reads an
empty chat template once a model is auto-selected.

Read serverStore.props.chat_template directly in non-router mode,
since the global /props already describes the single loaded model.
---
 tools/ui/src/lib/stores/models.svelte.ts | 40 ++++++++++++++----------
 1 file changed, 23 insertions(+), 17 deletions(-)

diff --git a/tools/ui/src/lib/stores/models.svelte.ts b/tools/ui/src/lib/stores/models.svelte.ts
index 4c7c7cdfe..0b4d7b55d 100644
--- a/tools/ui/src/lib/stores/models.svelte.ts
+++ b/tools/ui/src/lib/stores/models.svelte.ts
@@ -245,21 +245,20 @@ class ModelsStore {
 	 * Whether the selected model's chat template supports thinking/reasoning.
 	 * Uses heuristic detection on the model's chat_template from /props.
 	 *
-	 * - MODEL mode: uses serverStore.props.chat_template (single loaded model)
-	 * - ROUTER mode: fetches /props?model=<id> for the selected model (cached)
-	 *
-	 * Triggers an async fetch of model props if not yet cached in ROUTER mode.
+	 * - MODEL mode: the global /props already describes the single loaded model,
+	 *   so its chat_template is used directly and no per-model cache is involved
+	 * - ROUTER mode: fetches /props?model=<id> for the selected model (cached),
+	 *   triggering an async fetch if not yet cached
 	 */
 	get supportsThinking(): boolean {
-		const modelId = this.selectedModelName;
-		if (!modelId) {
-			if (!isRouterMode()) {
-				return detectThinkingSupport(serverStore.props?.chat_template ?? '');
-			}
-			return false;
+		if (!isRouterMode()) {
+			return detectThinkingSupport(serverStore.props?.chat_template ?? '');
 		}
 
-		if (isRouterMode() && !this.modelPropsCache.get(modelId)) {
+		const modelId = this.selectedModelName;
+		if (!modelId) return false;
+
+		if (!this.modelPropsCache.get(modelId)) {
 			this.fetchModelProps(modelId);
 		}
 		const props = this.getModelProps(modelId);
@@ -268,12 +267,17 @@ class ModelsStore {
 
 	/**
 	 * Check if a specific model supports thinking.
-	 * Fetches model props if not cached (in router mode).
+	 * In MODEL mode the global /props describes the single loaded model.
+	 * In ROUTER mode, fetches model props if not cached.
 	 */
 	checkModelSupportsThinking(modelId: string): boolean {
+		if (!isRouterMode()) {
+			return detectThinkingSupport(serverStore.props?.chat_template ?? '');
+		}
+
 		if (!modelId) return false;
 
-		if (isRouterMode() && !this.modelPropsCache.get(modelId)) {
+		if (!this.modelPropsCache.get(modelId)) {
 			this.fetchModelProps(modelId);
 		}
 
@@ -285,14 +289,16 @@ class ModelsStore {
 	 * Detailed thinking support detection result with reason for debugging/UI.
 	 */
 	get thinkingSupportDetails(): { supported: boolean; reason: string } {
+		if (!isRouterMode()) {
+			return detectThinkingSupportWithReason(serverStore.props?.chat_template ?? '');
+		}
+
 		const modelId = this.selectedModelName;
 		if (!modelId) {
-			if (!isRouterMode()) {
-				return detectThinkingSupportWithReason(serverStore.props?.chat_template ?? '');
-			}
 			return { supported: false, reason: 'No model selected' };
 		}
-		if (isRouterMode() && !this.modelPropsCache.get(modelId)) {
+
+		if (!this.modelPropsCache.get(modelId)) {
 			this.fetchModelProps(modelId);
 		}
 		const props = this.getModelProps(modelId);