Phase 4 : boucle agentique, outils fichiers et aperçu live

Backend :
- tools.py : read_file / write_file / list_dir confinés au workspace (anti-traversal)
- agent.py : boucle de tool-calling itérative au-dessus d'Ollama, génère des
  événements (token, tool_call, tool_result, final)
- routes/chat.py : pilote run_agent, relaie les événements en SSE, persiste la
  réponse finale + le récap des outils (meta)
- routes/files.py : arborescence et contenu du workspace (confiné)
- db.py : colonne meta sur messages (+ migration douce), list_messages_for_model

Frontend :
- ToolCard : carte d'appel d'outil dans le fil (statut en cours/terminé/échec)
- streamChat : événements tool_call / tool_result
- store : streamTools, fileTree, preview (ouverture auto d'un HTML écrit)
- LeftPanel : arborescence réelle du workspace, clic -> aperçu
- PreviewPanel : rendu HTML en iframe + onglet Code
- ChatPanel : rendu des outils dans les bulles agent (streaming + persisté)

Tests manuels : outils + confinement, boucle agent (mock Ollama), chat HTTP de
bout en bout (SSE, persistance meta, fichiers écrits, confinement route).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SVay7z3y7q2gEe54ByAE6N

frontend/src/api/client.ts

@@ -38,15 +38,42 @@ export interface Session {
   message_count?: number;
 }
 
+export interface ToolCall {
+  name: string;
+  args: Record<string, unknown>;
+  summary?: string;
+  status?: "ok" | "error" | "running";
+}
+
 export interface Message {
   id: string;
   session_id: string;
   role: "user" | "assistant";
   content: string;
   model?: string;
+  meta?: { tools?: ToolCall[] } | null;
   created_at: number;
 }
 
+export interface FileNode {
+  name: string;
+  path: string;
+  type: "dir" | "file";
+  size?: number;
+  children?: FileNode[];
+}
+
+export async function listFiles(): Promise<FileNode[]> {
+  const res = await fetch("/api/files");
+  return (await res.json()).tree;
+}
+
+export async function fileContent(path: string): Promise<string> {
+  const res = await fetch(`/api/files/content?path=${encodeURIComponent(path)}`);
+  if (!res.ok) return "";
+  return (await res.json()).content;
+}
+
 export async function listSessions(): Promise<Session[]> {
   const res = await fetch("/api/sessions");
   return (await res.json()).sessions;
@@ -77,6 +104,8 @@ export async function streamChat(
   body: { session_id: string; content: string; model?: string },
   handlers: {
     onToken: (t: string) => void;
+    onToolCall: (call: ToolCall) => void;
+    onToolResult: (call: ToolCall) => void;
     onDone: (full: string) => void;
     onError: (msg: string) => void;
   }
@@ -113,6 +142,9 @@ export async function streamChat(
       try {
         const payload = JSON.parse(data);
         if (event === "token") handlers.onToken(payload.content);
+        else if (event === "tool_call")
+          handlers.onToolCall({ ...payload, status: "running" });
+        else if (event === "tool_result") handlers.onToolResult(payload);
         else if (event === "done") handlers.onDone(payload.content);
         else if (event === "error") handlers.onError(payload.message);
       } catch {

frontend/src/components/ToolCard.tsx

@@ -0,0 +1,84 @@
+import type { ToolCall } from "../api/client";
+
+/** Carte d'appel d'outil rendue dans le fil (fidèle à la maquette). */
+export function ToolCard({ call }: { call: ToolCall }) {
+  const running = call.status === "running";
+  const error = call.status === "error";
+
+  // Argument principal affiché entre parenthèses (path le plus souvent).
+  const argPreview =
+    typeof call.args?.path === "string"
+      ? `("${call.args.path}")`
+      : Object.keys(call.args ?? {}).length
+      ? "(…)"
+      : "()";
+
+  return (
+    <div className="mb-[9px] overflow-hidden rounded-[11px] border border-line bg-card-deep">
+      <div className="flex items-center gap-2.5 px-[13px] py-2.5">
+        <span
+          className="flex h-6 w-6 items-center justify-center rounded-[7px] text-accent"
+          style={{ background: "rgba(240,161,92,.13)" }}
+        >
+          <ToolGlyph name={call.name} />
+        </span>
+        <span className="font-mono text-[12.5px] font-semibold text-[#e7ddcd]">
+          {call.name}
+        </span>
+        <span className="font-mono text-xs text-muted-2">{argPreview}</span>
+        <div className="flex-1" />
+        {running ? (
+          <span className="flex items-center gap-1.5 font-mono text-[11px] text-muted">
+            <span className="h-2.5 w-2.5 animate-spin rounded-full border-2 border-muted-3 border-t-accent" />
+            en cours
+          </span>
+        ) : (
+          <span
+            className={`flex items-center gap-1.5 font-mono text-[11px] ${
+              error ? "text-warn" : "text-ok"
+            }`}
+          >
+            {error ? "✕ échec" : "✓ terminé"}
+          </span>
+        )}
+      </div>
+      {call.summary && !running && (
+        <div className="border-t border-line-soft px-[13px] py-2.5 font-mono text-[11.5px] text-muted-3">
+          → {call.summary}
+        </div>
+      )}
+    </div>
+  );
+}
+
+function ToolGlyph({ name }: { name: string }) {
+  const common = {
+    width: 13,
+    height: 13,
+    viewBox: "0 0 24 24",
+    fill: "none",
+    stroke: "currentColor",
+    strokeWidth: 1.9,
+    strokeLinecap: "round" as const,
+    strokeLinejoin: "round" as const,
+  };
+  if (name === "write_file")
+    return (
+      <svg {...common}>
+        <path d="M5 19h14M7 14l9-9 3 3-9 9-4 1z" />
+      </svg>
+    );
+  if (name === "list_dir")
+    return (
+      <svg {...common}>
+        <path d="M4 7h6l2 2h8v9H4z" />
+      </svg>
+    );
+  // read_file (défaut)
+  return (
+    <svg {...common}>
+      <path d="M7 4h7l4 4v12H7z" />
+      <path d="M14 4v4h4" />
+    </svg>
+  );
+}

frontend/src/panels/ChatPanel.tsx

@@ -1,7 +1,8 @@
 import { useEffect, useRef, useState } from "react";
 import { useStore } from "../store/useStore";
 import { ClipIcon, LokiMark, SendIcon } from "../components/Icon";
-import type { Message } from "../api/client";
+import { ToolCard } from "../components/ToolCard";
+import type { Message, ToolCall } from "../api/client";
 
 /** Panneau central : barre de contexte, fil de conversation, composer. */
 export function ChatPanel() {
@@ -10,6 +11,7 @@ export function ChatPanel() {
     messages,
     streaming,
     streamContent,
+    streamTools,
     sendMessage,
     currentSessionId,
   } = useStore();
@@ -20,7 +22,7 @@ export function ChatPanel() {
   // Auto-scroll vers le bas à chaque token / message.
   useEffect(() => {
     scrollRef.current?.scrollTo({ top: scrollRef.current.scrollHeight });
-  }, [messages, streamContent]);
+  }, [messages, streamContent, streamTools]);
 
   const submit = () => {
     if (!draft.trim() || streaming) return;
@@ -43,7 +45,7 @@ export function ChatPanel() {
       <div className="flex h-[42px] flex-none items-center gap-2 border-b border-line-soft px-[18px]">
         <Chip>Invite système</Chip>
         <Chip>
-          <span className="h-1.5 w-1.5 rounded-full bg-ok" />0 outil actif
+          <span className="h-1.5 w-1.5 rounded-full bg-ok" />3 outils actifs
         </Chip>
         <Chip>
           Température <b className="font-semibold text-[#e7ddcd]">0.7</b>
@@ -82,6 +84,7 @@ export function ChatPanel() {
                   role: "assistant",
                   content: streamContent,
                   model: selectedModel,
+                  meta: { tools: streamTools },
                   created_at: Date.now() / 1000,
                 }}
                 pending
@@ -172,12 +175,17 @@ function Bubble({ msg, pending }: { msg: Message; pending?: boolean }) {
             {time}
           </span>
         </div>
-        <div className="text-sm leading-[1.65] text-ink-2 whitespace-pre-wrap">
-          {msg.content}
-          {pending && (
-            <span className="ml-0.5 inline-block h-3.5 w-[7px] animate-pulse bg-accent align-middle" />
-          )}
-        </div>
+        {(msg.meta?.tools ?? []).map((t: ToolCall, i: number) => (
+          <ToolCard key={i} call={t} />
+        ))}
+        {(msg.content || pending) && (
+          <div className="text-sm leading-[1.65] text-ink-2 whitespace-pre-wrap">
+            {msg.content}
+            {pending && (
+              <span className="ml-0.5 inline-block h-3.5 w-[7px] animate-pulse bg-accent align-middle" />
+            )}
+          </div>
+        )}
       </div>
     </div>
   );

frontend/src/panels/LeftPanel.tsx

@@ -1,6 +1,7 @@
 import { useEffect } from "react";
 import { useStore } from "../store/useStore";
 import { PlusIcon } from "../components/Icon";
+import type { FileNode } from "../api/client";
 
 /** Panneau gauche : historique des sessions + arborescence de fichiers. */
 export function LeftPanel() {
@@ -8,6 +9,8 @@ export function LeftPanel() {
     sessions,
     currentSessionId,
     refreshSessions,
+    refreshFiles,
+    fileTree,
     newSession,
     openSession,
     removeSession,
@@ -15,7 +18,8 @@ export function LeftPanel() {
 
   useEffect(() => {
     refreshSessions();
-  }, [refreshSessions]);
+    refreshFiles();
+  }, [refreshSessions, refreshFiles]);
 
   return (
     <div className="flex w-[268px] flex-none flex-col border-r border-line-soft bg-panel">
@@ -91,16 +95,60 @@ export function LeftPanel() {
       </div>
 
       <div className="scr flex-1 overflow-auto px-2.5 pb-3.5 font-mono text-xs">
-        <div className="px-2 py-4 text-center text-muted-3">
-          Aucun fichier pour l'instant.
-          <br />
-          L'agent créera des fichiers ici.
-        </div>
+        {fileTree.length === 0 ? (
+          <div className="px-2 py-4 text-center text-muted-3">
+            Aucun fichier pour l'instant.
+            <br />
+            L'agent créera des fichiers ici.
+          </div>
+        ) : (
+          <FileTree nodes={fileTree} depth={0} />
+        )}
       </div>
     </div>
   );
 }
 
+function FileTree({ nodes, depth }: { nodes: FileNode[]; depth: number }) {
+  const openPreview = useStore((s) => s.openPreview);
+  return (
+    <>
+      {nodes.map((n) => (
+        <div key={n.path}>
+          <div
+            onClick={() => n.type === "file" && openPreview(n.path)}
+            className={`flex items-center gap-2 rounded-[7px] px-2 py-[5px] ${
+              n.type === "file"
+                ? "cursor-pointer text-ink-2 hover:bg-[#221e18]"
+                : "text-muted"
+            }`}
+            style={{ paddingLeft: 8 + depth * 14 }}
+          >
+            {n.type === "dir" ? (
+              <svg
+                width="11"
+                height="11"
+                viewBox="0 0 24 24"
+                fill="none"
+                stroke="currentColor"
+                strokeWidth="2.4"
+                strokeLinecap="round"
+                strokeLinejoin="round"
+              >
+                <path d="m6 9 6 6 6-6" />
+              </svg>
+            ) : (
+              <span className="h-1.5 w-1.5 rounded-[1.5px] bg-accent" />
+            )}
+            <span className="truncate">{n.name}</span>
+          </div>
+          {n.children && <FileTree nodes={n.children} depth={depth + 1} />}
+        </div>
+      ))}
+    </>
+  );
+}
+
 function relTime(ts: number): string {
   const diff = Date.now() / 1000 - ts;
   if (diff < 60) return "à l'instant";

frontend/src/panels/PreviewPanel.tsx

@@ -1,17 +1,25 @@
-/** Panneau droit : onglets Aperçu / Code / Logs + zone d'aperçu. */
+import { useState } from "react";
+import { useStore } from "../store/useStore";
+
+type TabId = "preview" | "code";
+
+/** Panneau droit : onglets Aperçu / Code + rendu du fichier sélectionné. */
 export function PreviewPanel() {
+  const { previewPath, previewContent } = useStore();
+  const [tab, setTab] = useState<TabId>("preview");
+
+  const isHtml = previewPath ? /\.html?$/.test(previewPath) : false;
+
   return (
     <div className="flex w-[452px] flex-none flex-col border-l border-line-soft bg-panel">
       {/* Onglets */}
       <div className="flex h-[42px] flex-none items-center gap-1 border-b border-line-soft px-3.5 pr-2">
         <div className="flex gap-0.5">
-          <Tab active>Aperçu</Tab>
-          <Tab>Code</Tab>
-          <Tab>
-            Logs
-            <span className="ml-1.5 rounded-[5px] bg-line-strong px-1.5 py-px font-mono text-[10px] text-muted">
-              0
-            </span>
+          <Tab active={tab === "preview"} onClick={() => setTab("preview")}>
+            Aperçu
+          </Tab>
+          <Tab active={tab === "code"} onClick={() => setTab("code")}>
+            Code
           </Tab>
         </div>
       </div>
@@ -19,36 +27,61 @@ export function PreviewPanel() {
       {/* URL bar */}
       <div className="flex flex-none items-center gap-2 px-3.5 py-[9px]">
         <div className="flex h-[30px] flex-1 items-center gap-2 rounded-lg border border-line bg-sunken px-[11px]">
-          <span className="font-mono text-[11.5px] text-muted-3">
-            workspace/
+          <span className="truncate font-mono text-[11.5px] text-muted-3">
+            {previewPath ? `workspace/${previewPath}` : "workspace/"}
           </span>
         </div>
       </div>
 
       {/* Viewport */}
       <div className="scr mx-3.5 mb-3.5 flex-1 overflow-auto rounded-xl border border-line bg-[#faf6ef]">
-        <div className="flex h-full flex-col items-center justify-center gap-2 p-8 text-center">
-          <div className="font-mono text-[11px] text-[#a98b63]">
-            [ aucun aperçu ]
-          </div>
-          <div className="max-w-[240px] text-xs text-[#8a7a66]">
-            L'aperçu HTML s'affichera ici dès que l'agent générera une page.
-          </div>
-        </div>
+        {!previewPath ? (
+          <Empty>
+            L'aperçu s'affichera ici dès que l'agent générera un fichier (clique
+            aussi un fichier à gauche).
+          </Empty>
+        ) : tab === "code" ? (
+          <pre className="m-0 whitespace-pre-wrap p-4 font-mono text-[11.5px] leading-relaxed text-[#2a2018]">
+            {previewContent}
+          </pre>
+        ) : isHtml ? (
+          <iframe
+            title="aperçu"
+            srcDoc={previewContent}
+            className="h-full w-full border-0 bg-white"
+            sandbox="allow-same-origin"
+          />
+        ) : (
+          <pre className="m-0 whitespace-pre-wrap p-4 font-mono text-[11.5px] leading-relaxed text-[#2a2018]">
+            {previewContent}
+          </pre>
+        )}
       </div>
     </div>
   );
 }
 
+function Empty({ children }: { children: React.ReactNode }) {
+  return (
+    <div className="flex h-full flex-col items-center justify-center gap-2 p-8 text-center">
+      <div className="font-mono text-[11px] text-[#a98b63]">[ aucun aperçu ]</div>
+      <div className="max-w-[240px] text-xs text-[#8a7a66]">{children}</div>
+    </div>
+  );
+}
+
 function Tab({
   children,
   active,
+  onClick,
 }: {
   children: React.ReactNode;
   active?: boolean;
+  onClick?: () => void;
 }) {
   return (
-    <div
+    <button
+      onClick={onClick}
       className={`flex h-7 items-center rounded-lg px-[13px] text-[12.5px] ${
         active
           ? "bg-[#252019] font-semibold text-ink"
@@ -56,6 +89,6 @@ function Tab({
       }`}
     >
       {children}
-    </div>
+    </button>
   );
 }

frontend/src/store/useStore.ts

@@ -5,12 +5,16 @@ import {
   getModels,
   getSession,
   getStatus,
+  fileContent,
+  listFiles,
   listSessions,
   streamChat,
+  type FileNode,
   type Message,
   type OllamaModel,
   type OllamaStatus,
   type Session,
+  type ToolCall,
 } from "../api/client";
 
 interface LokiState {
@@ -24,10 +28,17 @@ interface LokiState {
   messages: Message[];
   streaming: boolean;
   streamContent: string; // réponse de l'agent en cours de frappe
+  streamTools: ToolCall[]; // appels d'outils de la réponse en cours
 
+  fileTree: FileNode[];
+  previewPath: string | null;
+  previewContent: string;
+
+  openPreview: (path: string) => Promise<void>;
   setSelectedModel: (name: string) => void;
   refreshStatus: () => Promise<void>;
   refreshModels: () => Promise<void>;
+  refreshFiles: () => Promise<void>;
 
   refreshSessions: () => Promise<void>;
   newSession: () => Promise<void>;
@@ -47,9 +58,26 @@ export const useStore = create<LokiState>((set, get) => ({
   messages: [],
   streaming: false,
   streamContent: "",
+  streamTools: [],
+  fileTree: [],
+  previewPath: null,
+  previewContent: "",
+
+  openPreview: async (path) => {
+    const content = await fileContent(path);
+    set({ previewPath: path, previewContent: content });
+  },
 
   setSelectedModel: (name) => set({ selectedModel: name }),
 
+  refreshFiles: async () => {
+    try {
+      set({ fileTree: await listFiles() });
+    } catch {
+      /* workspace indisponible */
+    }
+  },
+
   refreshStatus: async () => {
     try {
       const status = await getStatus();
@@ -122,17 +150,42 @@ export const useStore = create<LokiState>((set, get) => ({
       messages: [...get().messages, userMsg],
       streaming: true,
       streamContent: "",
+      streamTools: [],
     });
 
     await streamChat(
       { session_id: sid, content, model: get().selectedModel || undefined },
       {
         onToken: (t) => set({ streamContent: get().streamContent + t }),
+        onToolCall: (call) =>
+          set({ streamTools: [...get().streamTools, call] }),
+        onToolResult: (call) => {
+          // Met à jour le dernier outil correspondant (statut + résumé).
+          const tools = [...get().streamTools];
+          for (let i = tools.length - 1; i >= 0; i--) {
+            if (tools[i].name === call.name && tools[i].status === "running") {
+              tools[i] = { ...tools[i], ...call };
+              break;
+            }
+          }
+          set({ streamTools: tools });
+        },
         onDone: async () => {
-          set({ streaming: false, streamContent: "" });
-          // Recharge depuis la base pour récupérer les ids/horodatages réels.
+          // Repère un fichier HTML écrit pour l'afficher automatiquement.
+          const writtenHtml = [...get().streamTools]
+            .reverse()
+            .find(
+              (t) =>
+                t.name === "write_file" &&
+                typeof t.args?.path === "string" &&
+                /\.html?$/.test(t.args.path as string)
+            );
+          set({ streaming: false, streamContent: "", streamTools: [] });
+          // Recharge depuis la base + l'arborescence (fichiers créés par l'agent).
           if (get().currentSessionId === sid) await get().openSession(sid!);
           await get().refreshSessions();
+          await get().refreshFiles();
+          if (writtenHtml) await get().openPreview(writtenHtml.args.path as string);
         },
         onError: (msg) => {
           const errMsg: Message = {
@@ -145,6 +198,7 @@ export const useStore = create<LokiState>((set, get) => ({
           set({
             streaming: false,
             streamContent: "",
+            streamTools: [],
             messages: [...get().messages, errMsg],
           });
         },