Remove not needed context for subagent..

Author: beacoder

python_agent_harness/prompts.py

@@ -151,9 +151,11 @@ def load_context_files(context_dir: "Path | str | None") -> str | None:
 def load_task_completion_rules() -> str | None:
     """Load ``prompts/task-completion-rules.txt``, or None if unavailable.
 
-    These rules are injected automatically into every agent system
-    prompt (main agent, sub-agents, and session commands), so the model
-    never stops before the task is fully completed and verified.
+    These rules are injected automatically into the main agent and
+    session-command system prompts, so the model never stops before the
+    task is fully completed and verified.  Sub-agents are intentionally
+    excluded: they get ONLY their own prompt (subagent.txt) with no
+    extra context injected.
     """
     p = Path(__file__).parent / "prompts" / "task-completion-rules.txt"
     try:
@@ -177,8 +179,11 @@ def assemble_agent_prompt(
     context piece, immediately before the agent prompt, so they read as
     global ground rules rather than part of the task instructions.
 
-    ``include_context=False`` drops the project context files (used for
-    sub-agents, which get the rules but not the parent's context).
+    ``include_context=False`` drops the project context files (rules are
+    still included).  This function is NOT used for sub-agents: their
+    system prompt is their own prompt file (subagent.txt) only, with no
+    context files and no task-completion rules (see
+    ``cli.make_session`` and ``subagent._subagent_system_prompt``).
     ``context_path`` overrides the default context directory discovery.
     Returns None if every part is empty/missing.
     """

tests/test_context_rules.py

@@ -1,6 +1,7 @@
 """task-completion-rules.txt must be auto-injected into the system prompt:
 it is the LAST context piece, immediately before the actual agent prompt —
-for the main agent, sub-agents, session commands, and the TUI slash path.
+for the main agent, session commands, and the TUI slash path.  Sub-agents
+are excluded by design: their system prompt is subagent.txt ONLY.
 """
 
 import tempfile
@@ -41,6 +42,8 @@ def test_assemble_order_context_rules_agent(self):
             self.assertLess(i_rules, i_agent)
 
     def test_assemble_rules_before_agent_without_context(self):
+        """include_context=False keeps the rules (this path is NOT used
+        for sub-agents — they get subagent.txt only)."""
         prompt = assemble_agent_prompt("/tmp", "AGENT PROMPT", include_context=False)
         self.assertLess(
             prompt.index("Task Completion Rules"), prompt.index("AGENT PROMPT")

tests/test_subagent.py

@@ -74,6 +74,23 @@ def test_falls_back_to_default_subagent_prompt_when_missing(self):
         self.assertEqual(session.client.systems, [default_sub])
         self.assertNotIn("MAIN AGENT PROMPT", session.client.systems[0])
 
+    def test_subagent_prompt_never_includes_rules_or_context(self):
+        """The sub-agent's system prompt is subagent.txt ONLY — no
+        task-completion rules and no project context, even when the
+        parent's system prompt carries both."""
+        parent = (
+            "Request context:\n\nIn file `/tmp/contexts/general-rules.md`:"
+            "\n```\nGENERAL CONTEXT\n```\n\n"
+            "Task Completion Rules\n\nMAIN AGENT PROMPT"
+        )
+        session = make_session(parent, None, self._tmp.name)
+        run_subagent(session, "task", "do something")
+        system = session.client.systems[0]
+        self.assertNotIn("Task Completion Rules", system)
+        self.assertNotIn("Request context:", system)
+        self.assertNotIn("GENERAL CONTEXT", system)
+        self.assertNotIn("MAIN AGENT PROMPT", system)
+
     def test_plan_mode_reminder_prepended_but_prompt_still_subagent(self):
         session = make_session("MAIN", "SUB", self._tmp.name)
         session.plan_mode.set_mode(session.plan_mode.mode.PLAN, {