feat(prompt): per-invocation persona scope (#380) (#493)

Adds --persona NAME / --persona none and a [memory_files].persona_name config field, resolving ~/.openjarvis/personas/<name>/{SOUL,MEMORY,USER}.md. Default (empty) preserves today's global-persona behavior exactly. Includes a path-traversal guard on persona names. Resolution lives in SystemPromptBuilder._resolve_persona so all callers benefit. Squad-derived: Ada (Qwen3.6-27B) authored the spec independently from the issue+code; Lucy (Qwen3-Coder-Next, 80B-A3B / ~3B active) implemented it; cross-function param threading completed in the test phase. 21 existing tests pass; +8 new persona-scope tests.

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

src/openjarvis/cli/ask.py

@@ -151,9 +151,7 @@ def _run_research(
             trace.print(f"  [dim]↳ Found {n} {label}[/dim]")
         elif etype == "clarify_call":
             q = event.get("question", "") or ""
-            trace.print(
-                f"  [dim]↳ Clarifying:[/dim] [dim italic]{q}[/dim italic]"
-            )
+            trace.print(f"  [dim]↳ Clarifying:[/dim] [dim italic]{q}[/dim italic]")
         # final_answer and clarify_response are handled outside the loop.
 
     agent = ResearchAgent(
@@ -326,6 +324,7 @@ def _run_agent(
     temperature: float,
     max_tokens: int,
     capability_policy=None,
+    memory_files_config=None,
 ):
     """Instantiate and run an agent, returning the AgentResult."""
     # Import agents to trigger registration
@@ -374,7 +373,7 @@ def _run_agent(
 
         agent_kwargs["prompt_builder"] = SystemPromptBuilder(
             agent_template=config.agent.default_system_prompt or "",
-            memory_files_config=config.memory_files,
+            memory_files_config=memory_files_config or config.memory_files,
             system_prompt_config=config.system_prompt,
         )
 
@@ -592,6 +591,15 @@ def _print_profile(
         "(default: ~/.openjarvis/knowledge.db)."
     ),
 )
+@click.option(
+    "--persona",
+    "persona_name",
+    default=None,
+    help=(
+        "Named persona dir under ~/.openjarvis/personas/<name>/ "
+        "(overrides config). Pass 'none' to disable all persona files."
+    ),
+)
 @click.pass_context
 def ask(
     ctx: click.Context,
@@ -608,6 +616,7 @@ def ask(
     enable_profile: bool,
     research_mode: bool,
     knowledge_db: str | None,
+    persona_name: str | None,
 ) -> None:
     """Ask Jarvis a question."""
     quiet = (ctx.obj or {}).get("quiet", False) or output_json
@@ -620,6 +629,15 @@ def ask(
     # Load config
     config = load_config()
 
+    # Resolve effective MemoryFilesConfig with --persona override
+    import dataclasses as _dc
+
+    effective_mf = (
+        _dc.replace(config.memory_files, persona_name=persona_name)
+        if persona_name is not None
+        else config.memory_files
+    )
+
     # Honor `agent.default_agent` from config when --agent was not explicitly
     # passed. Pass `--agent ""` to opt out and use direct-to-engine mode.
     # Without this fallback, `[agent].default_system_prompt` and the
@@ -773,6 +791,7 @@ def ask(
                 temperature,
                 max_tokens,
                 capability_policy=sec.capability_policy,
+                memory_files_config=effective_mf,
             )
         except EngineConnectionError as exc:
             console.print(f"[red]Engine error:[/red] {exc}")

src/openjarvis/core/config.py

@@ -1428,6 +1428,7 @@ class MemoryFilesConfig:
     memory_path: str = "~/.openjarvis/MEMORY.md"
     user_path: str = "~/.openjarvis/USER.md"
     nudge_interval: int = 10
+    persona_name: str = ""  # named persona dir under ~/.openjarvis/personas/<name>/
 
 
 @dataclass(slots=True)

src/openjarvis/prompt/builder.py

@@ -35,7 +35,8 @@ class SystemPromptBuilder:
         skill_few_shot_examples: Optional[List[str]] = None,
     ) -> None:
         self._agent_template = agent_template
-        self._mf_config = memory_files_config or MemoryFilesConfig()
+        _mf = memory_files_config or MemoryFilesConfig()
+        self._mf_config = self._resolve_persona(_mf)
         self._sp_config = system_prompt_config or SystemPromptConfig()
         self._skill_index = skill_index or []
         self._session_context = session_context
@@ -250,3 +251,34 @@ class SystemPromptBuilder:
                 + text[-tail_size:]
             )
         return text[:max_chars] + "\n[...truncated...]"
+
+    @staticmethod
+    def _resolve_persona(mf: MemoryFilesConfig) -> MemoryFilesConfig:
+        """Resolve persona_name to effective file paths.
+        - "" (empty) -> use mf's existing paths (global default, unchanged)
+        - "none"      -> empty paths (opt-out, no persona injected)
+        - "<name>"    -> ~/.openjarvis/personas/<name>/{SOUL,MEMORY,USER}.md
+        """
+        if not mf.persona_name:
+            return mf
+        if mf.persona_name == "none":
+            return MemoryFilesConfig(
+                soul_path="",
+                memory_path="",
+                user_path="",
+                nudge_interval=mf.nudge_interval,
+            )
+        name = mf.persona_name
+        if ".." in name or "/" in name or "\\" in name or name.startswith("/"):
+            raise ValueError(
+                f"Invalid persona name {name!r}: must be a simple "
+                "identifier (no path separators or '..')."
+            )
+        base = Path.home() / ".openjarvis" / "personas" / name
+        return MemoryFilesConfig(
+            soul_path=str(base / "SOUL.md"),
+            memory_path=str(base / "MEMORY.md"),
+            user_path=str(base / "USER.md"),
+            nudge_interval=mf.nudge_interval,
+            persona_name=name,
+        )

tests/prompt/test_persona_scope.py

@@ -0,0 +1,33 @@
+"""Tests for #380 per-invocation persona scope (_resolve_persona)."""
+
+from pathlib import Path
+
+import pytest
+
+from openjarvis.core.config import MemoryFilesConfig
+from openjarvis.prompt.builder import SystemPromptBuilder
+
+
+def test_empty_persona_passes_through_global_defaults():
+    mf = MemoryFilesConfig()
+    out = SystemPromptBuilder._resolve_persona(mf)
+    assert out.soul_path == mf.soul_path  # unchanged = backward compatible
+
+
+def test_none_persona_disables_all_files():
+    out = SystemPromptBuilder._resolve_persona(MemoryFilesConfig(persona_name="none"))
+    assert out.soul_path == "" and out.memory_path == "" and out.user_path == ""
+
+
+def test_named_persona_resolves_to_personas_dir():
+    out = SystemPromptBuilder._resolve_persona(MemoryFilesConfig(persona_name="coder"))
+    base = str(Path.home() / ".openjarvis" / "personas" / "coder")
+    assert out.soul_path == f"{base}/SOUL.md"
+    assert out.memory_path == f"{base}/MEMORY.md"
+    assert out.user_path == f"{base}/USER.md"
+
+
+@pytest.mark.parametrize("bad", ["../etc", "a/b", "..\\win", "/abs", "x/../y"])
+def test_path_traversal_rejected(bad):
+    with pytest.raises(ValueError):
+        SystemPromptBuilder._resolve_persona(MemoryFilesConfig(persona_name=bad))