diff --git a/public/app/modelCapabilities.js b/public/app/modelCapabilities.js
index 3dc8745..fc09ba3 100644
--- a/public/app/modelCapabilities.js
+++ b/public/app/modelCapabilities.js
@@ -1,6 +1,12 @@
 // Conservative allowlist for models supporting the boolean think API.
 // Unknown models remain usable for normal chat.
-export function supportsReasoning(model) {
-    const id = String(typeof model === "string" ? model : model?.model || model?.name || "").toLowerCase().split("/").at(-1);
-    return /^(qwen3|deepseek-r1|deepseek-v3\.1)(:|$)/.test(id);
+const reasoningFamilies = new Set(["qwen3", "deepseek-r1", "deepseek-v3.1"]);
+
+export function getModelFamily(model) {
+    const id = typeof model === "string" ? model : model?.model || model?.name || model?.id || "";
+    return String(id).trim().toLowerCase().split("/").at(-1).split(":")[0];
+}
+
+export function supportsReasoning(model) {
+    return reasoningFamilies.has(getModelFamily(model));
 }
diff --git a/public/app/reasoning.js b/public/app/reasoning.js
index 745c07d..c7f4473 100644
--- a/public/app/reasoning.js
+++ b/public/app/reasoning.js
@@ -1,4 +1,4 @@
-import {supportsReasoning} from "./modelCapabilities.js";
+import {supportsReasoning} from "./modelCapabilities.js?v=20260921-reasoning-capability";
 
 export function createReasoningToggle(button) {
     let reasoningEnabled = false;
diff --git a/public/chat.html b/public/chat.html
index 2b94c1a..60f0abf 100644
--- a/public/chat.html
+++ b/public/chat.html
@@ -358,7 +358,7 @@
 
 <script src="https://cdn.jsdelivr.net/npm/marked/marked.min.js" defer></script>
 <script src="https://cdn.jsdelivr.net/npm/dompurify@3.0.6/dist/purify.min.js" defer></script>
-<script type="module" src="/script.js?v=20260909-account-controls"></script>
+<script type="module" src="/script.js?v=20260921-reasoning-capability"></script>
 <script type="module" src="/app/workspaceNavigation.js?v=20260909-account-controls"></script>
 </body>
 </html>
diff --git a/public/script.js b/public/script.js
index 9b8a403..a54e064 100644
--- a/public/script.js
+++ b/public/script.js
@@ -1,6 +1,6 @@
 import {del, get, post, put, stream} from "./app/api.js?v=20260909-account-controls";
 import {appendSources, createWebSearchToggle} from "./app/webSearch.js";
-import {createReasoningToggle, finishReasoning, updateReasoning} from "./app/reasoning.js";
+import {createReasoningToggle, finishReasoning, updateReasoning} from "./app/reasoning.js?v=20260921-reasoning-capability";
 import {closeChatDrawer, openChatDrawer} from "./app/chatDrawer.js?v=20260909-account-controls";
 import {onboardingPrompts, requestedChatId} from "./app/constants.js?v=20260909-account-controls";
 import {getModelProfile} from "./app/modelProfiles.js?v=20260909-account-controls";
diff --git a/test/reasoning.test.js b/test/reasoning.test.js
index 1dd51ff..442eb96 100644
--- a/test/reasoning.test.js
+++ b/test/reasoning.test.js
@@ -5,6 +5,7 @@ import {createApp} from "../src/app.js";
 import {createModelService} from "../src/services/modelService.js";
 import {stream} from "../public/app/api.js";
 import {createReasoningToggle, finishReasoning, updateReasoning} from "../public/app/reasoning.js";
+import {getModelFamily, supportsReasoning} from "../public/app/modelCapabilities.js";
 
 test("thinking streams separately and survives reload, retry, branch and import", async (t) => {
     const requests = [];
@@ -169,17 +170,20 @@ test("reasoning toggle defaults off, resets, and rejects unsupported models", ()
     const button = {setAttribute() {}, addEventListener(_event, callback) { this.click = callback; }};
     const toggle = createReasoningToggle(button);
     toggle.setModel("qwen3:14b");
+    assert.equal(button.disabled, false);
     assert.equal(toggle.enabled, false);
     assert.equal(button.title, "Enable reasoning");
     button.click();
     assert.equal(toggle.enabled, true);
     assert.equal(button.title, "Reasoning enabled");
+    assert.equal(button.disabled, false);
     toggle.setBusy(true);
     button.click();
     assert.equal(toggle.enabled, true);
     toggle.reset();
     assert.equal(toggle.enabled, false);
     toggle.setBusy(false);
+    assert.equal(button.disabled, false);
     button.click();
     toggle.setModel("mistral:latest");
     assert.equal(toggle.enabled, false);
@@ -188,3 +192,40 @@ test("reasoning toggle defaults off, resets, and rejects unsupported models", ()
     button.click();
     assert.equal(toggle.enabled, false);
 });
+
+test("tagged Qwen3 models enable the control without activating reasoning", () => {
+    for (const model of [
+        "qwen3:14b", "qwen3:8b", "qwen3:30b", "qwen3:latest",
+        " QWEN3:14b ", "library/qwen3:14b",
+        {model: "qwen3:14b"}, {name: "qwen3:8b"}, {id: "qwen3:latest"}
+    ]) {
+        assert.equal(getModelFamily(model), "qwen3");
+        assert.equal(supportsReasoning(model), true);
+        const attributes = {};
+        const button = {
+            disabled: true,
+            setAttribute(key, value) { attributes[key] = value; },
+            addEventListener(_event, callback) { this.click = callback; }
+        };
+        const toggle = createReasoningToggle(button);
+        toggle.setModel(""); // Model list has not loaded yet.
+        assert.equal(button.disabled, true);
+        toggle.setModel(model);
+        assert.equal(button.disabled, false);
+        assert.equal(toggle.enabled, false);
+        assert.equal(attributes["aria-pressed"], "false");
+        assert.equal(button.title, "Enable reasoning");
+        button.click();
+        assert.equal(toggle.enabled, true);
+        assert.equal(attributes["aria-pressed"], "true");
+        toggle.setModel(model); // A UI refresh must preserve the choice.
+        assert.equal(toggle.enabled, true);
+        toggle.reset();
+        assert.equal(toggle.enabled, false);
+        assert.equal(button.disabled, false);
+        assert.equal(button.title, "Enable reasoning");
+    }
+    for (const model of ["mistral:latest", "qwen2.5:14b", "qwen3-coder:30b", "qwen30:14b", "", null]) {
+        assert.equal(supportsReasoning(model), false);
+    }
+});