fix(ai): mode agent utilise les outils natifs au lieu du bloc obsigate-action (BUG-053)

backend/bookslm_routes.py

@@ -193,10 +193,12 @@ def _recent_files_for_prompt(current_user, limit: int = 10) -> list[dict[str, An
         return []
 
 
-def _resolve_system_prompt(req, current_user) -> str:
+def _resolve_system_prompt(req, current_user, agent: bool = False) -> str:
     """Resolve the vault access and build the assistant system prompt.
 
     Shared by the classic chat endpoint and the tool-calling agent endpoint.
+    ``agent=True`` selects the native-tool action protocol (no text
+    ``obsigate-action`` blocks) for the General/empty-directory prompts.
     """
     mode = _normalize_mode(req.mode)
     vault_path: Path | None = None
@@ -222,6 +224,7 @@ def _resolve_system_prompt(req, current_user) -> str:
             list(index.keys()),
             app_context=_submitted_app_context(req),
             recent_files=_recent_files_for_prompt(current_user),
+            agent=agent,
         )
     elif effective_mode == "documents":
         prompt = build_system_prompt(context, scope="documents", vault_name=req.vault)
@@ -233,6 +236,7 @@ def _resolve_system_prompt(req, current_user) -> str:
             list(index.keys()),
             app_context=_submitted_app_context(req),
             recent_files=_recent_files_for_prompt(current_user),
+            agent=agent,
         )
         prompt += (
             f"\n## Dossier vide\nLe dossier « {req.directory or '/'} » "
@@ -243,6 +247,14 @@ def _resolve_system_prompt(req, current_user) -> str:
     else:
         prompt = build_system_prompt(context, scope="directory", vault_name=req.vault)
 
+    if agent and effective_mode != "general" and context["file_count"] > 0:
+        prompt += (
+            "\n## Mode agent\n"
+            "Utilise les outils natifs (function calling) pour agir sur les fichiers "
+            "(`create_file`, `create_directory`, `append_to_file`, `edit_file`, …). "
+            "N'écris jamais de bloc ```obsigate-action```."
+        )
+
     skill_id = getattr(req, "skill", None)
     if skill_id:
         skill_prompt = get_skill_prompt(skill_id, current_user)
@@ -499,7 +511,7 @@ async def api_bookslm_agent(
     ``confirm`` / ``confirm_messages``.
     """
     _validate_vision_support(req)
-    system_prompt = _resolve_system_prompt(req, current_user)
+    system_prompt = _resolve_system_prompt(req, current_user, agent=True)
     vault_path = _resolve_optional_vault_path(req, current_user)
 
     messages: list[dict] = [{"role": "system", "content": system_prompt}]
@@ -519,7 +531,9 @@ async def api_bookslm_agent(
             provider=req.provider,
             model=req.model,
             temperature=0.3,
-            max_tokens=4096,
+            # Tool-call arguments can carry a whole file body (e.g. a generated
+            # table): leave more room than the plain-chat default.
+            max_tokens=8192,
         )
 
     async def generate_sse():