fix: remove hardcoded assistant acks after system message injection

s08/s09/s10/s11/s_full inject background-results and inbox as user
  messages before LLM calls. The paired hardcoded assistant "Noted..."
  responses were unnecessary — consecutive user messages work fine and
  the fake acks added noise with no functional value.

  Affected: agents/s08, s09, s10, s11, s_full + docs (zh/en/ja s08, s09)

agents/s08_background_tasks.py

@@ -194,7 +194,6 @@ def agent_loop(messages: list):
                 f"[bg:{n['task_id']}] {n['status']}: {n['result']}" for n in notifs
             )
             messages.append({"role": "user", "content": f"<background-results>\n{notif_text}\n</background-results>"})
-            messages.append({"role": "assistant", "content": "Noted background results."})
         response = client.messages.create(
             model=MODEL, system=SYSTEM, messages=messages,
             tools=TOOLS, max_tokens=8000,

agents/s09_agent_teams.py

@@ -350,10 +350,6 @@ def agent_loop(messages: list):
                 "role": "user",
                 "content": f"<inbox>{json.dumps(inbox, indent=2)}</inbox>",
             })
-            messages.append({
-                "role": "assistant",
-                "content": "Noted inbox messages.",
-            })
         response = client.messages.create(
             model=MODEL,
             system=SYSTEM,

agents/s10_team_protocols.py

@@ -431,10 +431,6 @@ def agent_loop(messages: list):
                 "role": "user",
                 "content": f"<inbox>{json.dumps(inbox, indent=2)}</inbox>",
             })
-            messages.append({
-                "role": "assistant",
-                "content": "Noted inbox messages.",
-            })
         response = client.messages.create(
             model=MODEL,
             system=SYSTEM,

agents/s11_autonomous_agents.py

@@ -515,10 +515,6 @@ def agent_loop(messages: list):
                 "role": "user",
                 "content": f"<inbox>{json.dumps(inbox, indent=2)}</inbox>",
             })
-            messages.append({
-                "role": "assistant",
-                "content": "Noted inbox messages.",
-            })
         response = client.messages.create(
             model=MODEL,
             system=SYSTEM,

agents/s_full.py

@@ -664,12 +664,10 @@ def agent_loop(messages: list):
         if notifs:
             txt = "\n".join(f"[bg:{n['task_id']}] {n['status']}: {n['result']}" for n in notifs)
             messages.append({"role": "user", "content": f"<background-results>\n{txt}\n</background-results>"})
-            messages.append({"role": "assistant", "content": "Noted background results."})
         # s10: check lead inbox
         inbox = BUS.read_inbox("lead")
         if inbox:
             messages.append({"role": "user", "content": f"<inbox>{json.dumps(inbox, indent=2)}</inbox>"})
-            messages.append({"role": "assistant", "content": "Noted inbox messages."})
         # LLM call
         response = client.messages.create(
             model=MODEL, system=SYSTEM, messages=messages,

docs/en/s08-background-tasks.md

@@ -81,8 +81,6 @@ def agent_loop(messages: list):
             messages.append({"role": "user",
                 "content": f"<background-results>\n{notif_text}\n"
                            f"</background-results>"})
-            messages.append({"role": "assistant",
-                "content": "Noted background results."})
         response = client.messages.create(...)
 ```
 

docs/en/s09-agent-teams.md

@@ -93,8 +93,6 @@ def _teammate_loop(self, name, role, prompt):
         if inbox != "[]":
             messages.append({"role": "user",
                 "content": f"<inbox>{inbox}</inbox>"})
-            messages.append({"role": "assistant",
-                "content": "Noted inbox messages."})
         response = client.messages.create(...)
         if response.stop_reason != "tool_use":
             break

docs/ja/s08-background-tasks.md

@@ -81,8 +81,6 @@ def agent_loop(messages: list):
             messages.append({"role": "user",
                 "content": f"<background-results>\n{notif_text}\n"
                            f"</background-results>"})
-            messages.append({"role": "assistant",
-                "content": "Noted background results."})
         response = client.messages.create(...)
 ```
 

docs/ja/s09-agent-teams.md

@@ -93,8 +93,6 @@ def _teammate_loop(self, name, role, prompt):
         if inbox != "[]":
             messages.append({"role": "user",
                 "content": f"<inbox>{inbox}</inbox>"})
-            messages.append({"role": "assistant",
-                "content": "Noted inbox messages."})
         response = client.messages.create(...)
         if response.stop_reason != "tool_use":
             break

docs/zh/s08-background-tasks.md

@@ -81,8 +81,6 @@ def agent_loop(messages: list):
             messages.append({"role": "user",
                 "content": f"<background-results>\n{notif_text}\n"
                            f"</background-results>"})
-            messages.append({"role": "assistant",
-                "content": "Noted background results."})
         response = client.messages.create(...)
 ```
 

docs/zh/s09-agent-teams.md

@@ -93,8 +93,6 @@ def _teammate_loop(self, name, role, prompt):
         if inbox != "[]":
             messages.append({"role": "user",
                 "content": f"<inbox>{inbox}</inbox>"})
-            messages.append({"role": "assistant",
-                "content": "Noted inbox messages."})
         response = client.messages.create(...)
         if response.stop_reason != "tool_use":
             break