cmux NEXT model picker: every harness its own tab again (claude-sr2 models back), and Claude Code gets full model ids

cmux-tui/crates/acpmux/src/claude_stdio/mod.rs

@@ -137,6 +137,22 @@ fn effort_value(effort: &str) -> &str {
     }
 }
 
+/// The model id Claude Code accepts for `value`. A versioned family name
+/// without the `claude-` prefix (`opus-5-5`, `sonnet-5-5[1m]`) is not a
+/// Claude Code alias: Claude Code sends it to the API as typed and every turn
+/// fails with "There's an issue with the selected model (opus-5-5)". It takes
+/// the prefix, as the live list's `launch_id` does. Bare aliases (`opus`,
+/// `opusplan`), full ids and other providers' names pass unchanged.
+pub fn model_id(value: &str) -> String {
+    let value = value.trim();
+    let versioned = ["opus-", "sonnet-", "haiku-"].iter().any(|family| {
+        value
+            .strip_prefix(family)
+            .is_some_and(|rest| rest.starts_with(|c: char| c.is_ascii_digit()))
+    });
+    if versioned { format!("claude-{value}") } else { value.to_owned() }
+}
+
 /// The Reasoning select's value for a session effort: Ultracode runs at xhigh.
 fn shown_level(effort: &str) -> &str {
     match effort_value(effort) {
@@ -375,7 +391,7 @@ pub fn spawn_plan(
     // A later --model wins over one the profile pins in its argv.
     if let Some(m) = model.filter(|m| !m.is_empty() && *m != "default") {
         args.push("--model".into());
-        args.push(m.into());
+        args.push(model_id(m));
     }
     // Lets the chat switch to bypassPermissions ("Bypass permissions") later; a
     // process that cannot take it is never given bypassPermissions at spawn.
@@ -593,7 +609,7 @@ impl Translator {
             session_id: Mutex::new(None),
             acp_session_id,
             mode: Mutex::new(mode.to_owned()),
-            model: Mutex::new(model.to_owned()),
+            model: Mutex::new(model_id(model)),
             effort: Mutex::new(effort_value(effort).to_owned()),
             fast: Mutex::new(false),
             in_turn: AtomicBool::new(false),

cmux-tui/crates/acpmux/src/claude_stdio/outbound.rs

@@ -150,6 +150,7 @@ impl Translator {
                         let val = p.get("value").and_then(Value::as_str).unwrap_or("").to_owned();
                         match cid {
                             "model" => {
+                                let val = super::model_id(&val);
                                 self.pending.lock().await.insert(
                                     id.to_string(),
                                     Pending::Control(Setting::Model, val.clone()),
@@ -244,8 +245,8 @@ impl Translator {
                         let val = p
                             .get("modelId")
                             .and_then(Value::as_str)
-                            .unwrap_or("default")
-                            .to_owned();
+                            .unwrap_or("default");
+                        let val = super::model_id(val);
                         self.pending
                             .lock()
                             .await

cmux-tui/crates/acpmux/src/claude_stdio/tests.rs

@@ -572,3 +572,39 @@ async fn modes_are_claude_codes_own_labels_descriptions_and_order() {
         mode["options"].as_array().unwrap().iter().filter_map(|o| o["value"].as_str()).collect();
     assert_eq!(values, ["auto", "default", "acceptEdits", "plan", "bypassPermissions"]);
 }
+
+/// A chat started with a versioned family name (`opus-5-5`, as a picker or
+/// an agent's `--model` may pass it) failed every turn: Claude Code sent it to
+/// the API unchanged ("There's an issue with the selected model (opus-5-5)").
+/// The translator hands Claude Code the full id at spawn and on every switch.
+#[tokio::test]
+async fn versioned_family_names_reach_claude_code_as_full_ids() {
+    assert_eq!(model_id("opus-5-5"), "claude-opus-5-5");
+    assert_eq!(model_id("sonnet-5-5[1m]"), "claude-sonnet-5-5[1m]");
+    for unchanged in ["opus", "opusplan", "opus[1m]", "claude-opus-5-5", "default", "gpt-6.1-sol"] {
+        assert_eq!(model_id(unchanged), unchanged);
+    }
+
+    let profile: crate::config::HarnessProfile =
+        serde_json::from_value(json!({"kind": "claude-stdio", "argv": ["claude"]})).unwrap();
+    let plan = spawn_plan(&profile, None, false, None, None, "default", Some("opus-5-5"));
+    let at = plan.args.iter().position(|a| a == "--model").expect("--model");
+    assert_eq!(plan.args[at + 1], "claude-opus-5-5");
+
+    let t = Translator::new("acp-1".into(), "default", "opus-5-5", "default");
+    assert_eq!(*t.model.lock().await, "claude-opus-5-5");
+    let req = Message::request(
+        3,
+        method::SESSION_SET_MODEL,
+        json!({"sessionId": "acp-1", "modelId": "haiku-5-5"}),
+    );
+    let Outbound::Lines(lines) = t.outbound(&req).await else { panic!() };
+    assert_eq!(lines[0]["request"]["model"], "claude-haiku-5-5");
+    let req = Message::request(
+        4,
+        method::SESSION_SET_CONFIG_OPTION,
+        json!({"sessionId": "acp-1", "configId": "model", "value": "sonnet-5-5"}),
+    );
+    let Outbound::Lines(lines) = t.outbound(&req).await else { panic!() };
+    assert_eq!(lines[0]["request"]["model"], "claude-sonnet-5-5");
+}

webviews/src/agent-session/acpmux/ModelPicker.gallery.tsx

@@ -74,11 +74,7 @@ const curated: ModelPickerProps = {
     .map((harness) => ({
       id: harness.id,
       name: harness.name,
-      models: harness.models.map((model) => ({
-        id: model.id,
-        name: model.name,
-        shortName: model.shortName,
-      })),
+      models: harness.models.map((model) => ({ id: model.id, name: model.name, shortName: model.shortName })),
       ...(topModelsFor(harness.id) ? { top: topModelsFor(harness.id) } : {}),
     })),
 };
@@ -185,11 +181,7 @@ const manyHarnesses: ModelPickerProps["catalog"] = [
     ["deepagents", "DeepAgents"],
     ["poolside", "Poolside"],
     ["qoder", "Qoder CLI"],
-  ].map(([id, name]) => ({
-    id: id!,
-    name: name!,
-    models: [{ id: `${id}-default`, name: "Default" }],
-  })),
+  ].map(([id, name]) => ({ id: id!, name: name!, models: [{ id: `${id}-default`, name: "Default" }] })),
 ];
 
 /// The open picker stays within the available anchor room on a tall stage, and its content
@@ -302,28 +294,12 @@ const startedFork: ModelPickerProps = {
   ...quick,
   catalog: [
     ...curated.catalog,
-    {
-      ...curated.catalog.find((entry) => entry.id === "claude")!,
-      id: "claude-work",
-      name: "Claude (work)",
-    },
+    { ...curated.catalog.find((entry) => entry.id === "claude")!, id: "claude-work", name: "Claude (work)" },
   ],
   harnessFixed: true,
   fork: { to: () => undefined, ready: true },
 };
 
-const canonicalVariants: ModelPickerProps = {
-  ...startedFork,
-  catalog: [
-    ...startedFork.catalog,
-    {
-      ...curated.catalog.find((entry) => entry.id === "codex")!,
-      id: "codex-work",
-      name: "Codex (work)",
-    },
-  ],
-};
-
 /// A short New Tab/chat pane with 48 installed accounts: the menu must cap to its window and
 /// let the Account list scroll to its last row without an empty spacer.
 const manyProfiles: ModelPickerProps = {
@@ -614,14 +590,6 @@ export default componentEntry<GalleryProps>({
         await ctx.waitFor(() => ctx.document.querySelector(".acpmux-quick-fork") !== null);
       },
     },
-    "canonical-harnesses-chat": {
-      props: canonicalVariants,
-      play: openQuick,
-    },
-    "canonical-harnesses-new-chat": {
-      props: { ...canonicalVariants, harnessFixed: false, fork: undefined, onHarness: () => undefined },
-      play: openQuick,
-    },
     // Its Account row contains signed-in routes, separate from named launch harnesses.
     "started-chat-accounts": {
       props: startedFork,

webviews/src/agent-session/acpmux/ModelPicker.tsx

@@ -41,7 +41,6 @@ import {
   PickerOptionList,
 } from "../../ui/PickerPrimitives";
 import { ScrollArea } from "../../ui/ScrollArea";
-import { canonicalHarnesses } from "./canonicalHarnesses";
 import { quantizePickerRail } from "./pickerRailGeometry";
 
 type HarnessChoice = {
@@ -299,15 +298,20 @@ function quickRow(family: string, model: ModelChoice): QuickModel {
 /// The rail's Starred tab (never a harness id).
 const STARRED = "\u0000starred";
 
-/// Build launch entries before folding Claude/Codex variants into their canonical harness tab.
-/// Their model catalogs refresh after selection; do not borrow another account's models.
+/// Global launch configurations are distinct harness entries, never a Profile submenu.
+/// One whose own catalog entry lists models shows them, as any harness tab does; only one with
+/// no models of its own launches from its tab. Do not borrow another account's models.
 function railByHarness(
   list: QuickFamily[],
   running: string | undefined,
   profiles: Readonly<Record<string, readonly PickerProfile[]>> = {},
   signedOut: (id: string) => boolean = () => false,
 ): QuickFamily[] {
   const seen = new Set<string>();
+  const byId = new Map(list.map((family) => [family.id, family]));
+  // Only a row that can be picked starts the entry; one whose probe failed keeps its launch tab.
+  const hasModels = (family: QuickFamily | undefined) =>
+    !!family && [...family.models, ...family.more].some((model) => !model.disabled);
   return list.flatMap((family) => {
     if (seen.has(family.id)) return [];
     seen.add(family.id);
@@ -323,7 +327,7 @@ function railByHarness(
     );
     const currentName =
       names.find((profile) => profile.id === family.id)?.name ?? launchName(family.name, family.name, family.id);
-    const alternate = launchSuffix(family.id) && family.id !== running;
+    const alternate = launchSuffix(family.id) && family.id !== running && !hasModels(family);
     const own = { ...family, name: currentName, ...(alternate ? { launch: true } : {}) };
     return [
       own,
@@ -338,6 +342,8 @@ function railByHarness(
         )
           return [];
         seen.add(profile.id);
+        const entry = byId.get(profile.id);
+        if (hasModels(entry)) return [{ ...entry!, name: profile.name, mark: entry!.mark ?? family.mark }];
         return [
           {
             id: profile.id,
@@ -929,10 +935,7 @@ export function ModelPicker(props: ModelPickerProps) {
           : {}),
       });
     }
-    const rail = canonicalHarnesses(
-      railByHarness(list, harness ?? current?.id, props.profiles, (id) => signedOut?.[id] !== undefined),
-      current?.id,
-    );
+    const rail = railByHarness(list, harness ?? current?.id, props.profiles, (id) => signedOut?.[id] !== undefined);
     if (!harnessFixed) return rail;
     // A started chat (Leo 2026-10-22: "can expose as fork"): another harness's tab is Fork to it,
     // Starred keeps the chat's own models, and another launch profile of any harness forks there.
@@ -943,7 +946,6 @@ export function ModelPicker(props: ModelPickerProps) {
         return models.length ? [{ ...family, models }] : [];
       }
       if (family.id === current?.id || family.note) return [own];
-      if (family.launch) return [{ ...own, models: [], more: [], fork: true }];
       return [{ ...own, models: [], more: [], fork: true }];
     });
   }, [

webviews/src/agent-session/acpmux/QuickModelMenu.tsx

@@ -128,8 +128,6 @@ export type QuickModel = {
 /// their place (a signed-out harness). `mark` is the AgentMark brand; without one the tab draws
 /// the name's initial.
 export type QuickFamily = {
-  /// Alternate launch configurations inside the canonical harness tab, never duplicate rail tabs.
-  variants?: QuickFamily[];
   id: string;
   name: string;
   mark?: string;
@@ -785,26 +783,6 @@ export function QuickModelMenu({
           )}
         </>
       )}
-      {!query && shown?.variants && shown.variants.length > 0 && (
-        <MenuGroup label={shown.name}>
-          {shown.variants.map((variant) => (
-            <MenuItem
-              key={variant.id}
-              className="acpmux-quick-item acpmux-quick-variant"
-              disabled={families?.forkReady === false}
-              closeOnClick
-              onSelect={() => {
-                if (variant.logIn) variant.logIn();
-                else families?.onLaunch?.(variant.id);
-              }}
-            >
-              <span className="acpmux-menu-label">
-                {families?.onFork ? t("picker.forkTo", { harness: variant.name }) : variant.name}
-              </span>
-            </MenuItem>
-          ))}
-        </MenuGroup>
-      )}
       {!query &&
         onChatTab &&
         effort &&