diff --git a/frontend/src/features/first-run/FirstRunWizard.test.tsx b/frontend/src/features/first-run/FirstRunWizard.test.tsx
index 7011ff5..4711f07 100644
--- a/frontend/src/features/first-run/FirstRunWizard.test.tsx
+++ b/frontend/src/features/first-run/FirstRunWizard.test.tsx
@@ -83,6 +83,30 @@ describe("FirstRunWizard (with MockProfileGateway)", () => {
     expect(cmd.value).toBe("codex-2");
   });
 
+  it("keeps args spaces while typing and parses them on blur", async () => {
+    const { profile } = renderWizard();
+    await waitForLoaded();
+    await waitFor(() =>
+      expect(
+        (screen.getByLabelText("use Claude Code") as HTMLInputElement).checked,
+      ).toBe(true),
+    );
+
+    const args = screen.getByLabelText("Claude Code args") as HTMLInputElement;
+    fireEvent.change(args, {
+      target: { value: "--model   claude-sonnet-4-5  --verbose " },
+    });
+    expect(args.value).toBe("--model   claude-sonnet-4-5  --verbose ");
+
+    fireEvent.blur(args);
+    fireEvent.click(screen.getByRole("button", { name: "Save and continue" }));
+
+    await waitFor(async () => {
+      const [saved] = await profile.listProfiles();
+      expect(saved.args).toEqual(["--model", "claude-sonnet-4-5", "--verbose"]);
+    });
+  });
+
   it("detection shows ✓ for claude and ✗ for the rest", async () => {
     renderWizard();
     await waitForLoaded();
diff --git a/frontend/src/features/first-run/FirstRunWizard.tsx b/frontend/src/features/first-run/FirstRunWizard.tsx
index edfcb7b..14bfd0e 100644
--- a/frontend/src/features/first-run/FirstRunWizard.tsx
+++ b/frontend/src/features/first-run/FirstRunWizard.tsx
@@ -20,6 +20,7 @@ import type {
   HttpChatConfig,
   LocalModelServerConfig,
 } from "@/domain";
+import { useEffect, useState } from "react";
 import { Button, IconButton, Input, Panel, Toolbar, cn } from "@/shared";
 import {
   ModelServersPanel,
@@ -183,6 +184,16 @@ function ProfileRow({
   const { profile, selected, available } = entry;
   const errors = validateProfile(profile);
   const isOpenCode = profile.structuredAdapter === "openCode";
+  const canonicalArgsText = profile.args.join(" ");
+  const [argsText, setArgsText] = useState(canonicalArgsText);
+
+  useEffect(() => {
+    setArgsText(canonicalArgsText);
+  }, [canonicalArgsText, profile.id]);
+
+  function commitArgs() {
+    onChange({ ...profile, args: parseArgs(argsText) });
+  }
 
   return (
     <li className="flex flex-col gap-2 rounded-md border border-border bg-raised p-3">
@@ -260,8 +271,9 @@ function ProfileRow({
         <Caption>Arguments</Caption>
         <Input
           aria-label={`${profile.name} args`}
-          value={profile.args.join(" ")}
-          onChange={(e) => onChange({ ...profile, args: parseArgs(e.target.value) })}
+          value={argsText}
+          onChange={(e) => setArgsText(e.target.value)}
+          onBlur={commitArgs}
         />
       </label>
 
diff --git a/frontend/src/features/model-servers/ModelServersPanel.tsx b/frontend/src/features/model-servers/ModelServersPanel.tsx
index ce7eb6d..e5236c1 100644
--- a/frontend/src/features/model-servers/ModelServersPanel.tsx
+++ b/frontend/src/features/model-servers/ModelServersPanel.tsx
@@ -97,9 +97,10 @@ export function ModelServersPanel({ vm }: ModelServersPanelProps) {
     setDraft({ ...server });
   }
 
-  async function submit() {
-    if (!draft) return;
-    const saved = await vm.save(draft);
+  async function submit(nextDraft?: LocalModelServerConfig) {
+    const submitted = nextDraft ?? draft;
+    if (!submitted) return;
+    const saved = await vm.save(submitted);
     if (saved) setDraft(null);
   }
 
@@ -225,7 +226,7 @@ export function ModelServersPanel({ vm }: ModelServersPanelProps) {
               vm.clearError();
               setDraft(null);
             }}
-            onSubmit={() => void submit()}
+            onSubmit={(nextDraft) => void submit(nextDraft)}
           />
         )}
       </div>
@@ -343,12 +344,27 @@ function ServerEditor({
   ) => Promise<ModelServerCommandPreview | null>;
   onChange: (next: LocalModelServerConfig) => void;
   onCancel: () => void;
-  onSubmit: () => void;
+  onSubmit: (nextDraft?: LocalModelServerConfig) => void;
 }) {
   const errors: ModelServerErrors = validateModelServer(draft);
   const valid = Object.keys(errors).length === 0;
   const patch = (next: Partial<LocalModelServerConfig>) =>
     onChange({ ...draft, ...next });
+  const canonicalArgsText = draft.args.join(" ");
+  const [argsText, setArgsText] = useState(canonicalArgsText);
+
+  useEffect(() => {
+    setArgsText(canonicalArgsText);
+  }, [canonicalArgsText, draft.id]);
+
+  function draftWithCommittedArgs(): LocalModelServerConfig {
+    return { ...draft, args: parseArgs(argsText) };
+  }
+
+  function commitArgs() {
+    const next = draftWithCommittedArgs();
+    onChange(next);
+  }
 
   // Sticky source tab: keep the chosen kind even when the field is momentarily
   // blank (an empty field clears `modelSource`, which must not snap the tab).
@@ -411,7 +427,7 @@ function ServerEditor({
     // `draftKey` captures the argv-affecting fields; `preview` is stable.
   }, [draftKey, preview]); // eslint-disable-line react-hooks/exhaustive-deps
 
-  const reservedHits = reservedFlagsIn(draft.args);
+  const reservedHits = reservedFlagsIn(parseArgs(argsText));
 
   return (
     <fieldset
@@ -642,9 +658,10 @@ function ServerEditor({
             <Caption>Arguments supplémentaires</Caption>
             <Input
               aria-label="extra arguments"
-              value={draft.args.join(" ")}
+              value={argsText}
               placeholder="--flash-attn --parallel 2"
-              onChange={(e) => patch({ args: parseArgs(e.target.value) })}
+              onChange={(e) => setArgsText(e.target.value)}
+              onBlur={commitArgs}
             />
             {reservedHits.length > 0 && (
               <small className="text-xs text-warning" role="status">
@@ -682,7 +699,7 @@ function ServerEditor({
           variant="primary"
           size="sm"
           aria-label="save model server"
-          onClick={onSubmit}
+          onClick={() => onSubmit(draftWithCommittedArgs())}
           disabled={busy || !valid}
         >
           Save server
diff --git a/frontend/src/features/model-servers/modelServers.test.tsx b/frontend/src/features/model-servers/modelServers.test.tsx
index 9a3f8c0..872f941 100644
--- a/frontend/src/features/model-servers/modelServers.test.tsx
+++ b/frontend/src/features/model-servers/modelServers.test.tsx
@@ -276,6 +276,33 @@ describe("ModelServersPanel wizard (F35 V2)", () => {
     expect(screen.getByText(/déjà pilotée par un champ/i)).toBeTruthy();
   });
 
+  it("keeps extra-args spaces while typing and only parses them on save", async () => {
+    const { modelServer } = renderPanel();
+    fireEvent.click(screen.getByLabelText("add model server"));
+
+    fireEvent.change(screen.getByLabelText("server name"), {
+      target: { value: "Spaced Args" },
+    });
+    fireEvent.change(screen.getByLabelText("hugging face model"), {
+      target: { value: "unsloth/Qwen3.5-9B-GGUF:Q4_K_M" },
+    });
+    const args = screen.getByLabelText("extra arguments") as HTMLInputElement;
+    fireEvent.change(args, {
+      target: { value: "--flash-attn   --parallel  2 " },
+    });
+
+    expect(args.value).toBe("--flash-attn   --parallel  2 ");
+
+    const save = screen.getByLabelText("save model server") as HTMLButtonElement;
+    await waitFor(() => expect(save.disabled).toBe(false));
+    fireEvent.click(save);
+
+    await waitFor(async () => {
+      const [saved] = await modelServer.listModelServers();
+      expect(saved.args).toEqual(["--flash-attn", "--parallel", "2"]);
+    });
+  });
+
   it("blocks auto-start until a model source is set", () => {
     renderPanel();
     fireEvent.click(screen.getByLabelText("add model server"));