fix(honcho): write config to instance-local path for profile isolation (NousResearch#4037)

Multiple agents/profiles running 'hermes honcho setup' all wrote to
the shared global ~/.honcho/config.json, overwriting each other's
configuration.

Root cause: _write_config() defaulted to resolve_config_path() which
returns the global path when no instance-local file exists yet (i.e.
on first setup).

Fix: _write_config() now defaults to _local_config_path() which always
returns $HERMES_HOME/honcho.json. Each profile gets its own config file.
Reading still falls back to global for cross-app interop and seeding.

Also updates cmd_setup and cmd_status messaging to show the actual
write path.

Includes 10 new tests verifying profile isolation, global fallback
reads, and multi-profile independence.

Author: melon-xf

honcho_integration/cli.py

@@ -10,16 +10,27 @@
 import sys
 from pathlib import Path
 
+from hermes_constants import get_hermes_home
 from honcho_integration.client import resolve_config_path, GLOBAL_CONFIG_PATH
 
 HOST = "hermes"
 
 
 def _config_path() -> Path:
-    """Return the active Honcho config path (instance-local or global)."""
+    """Return the active Honcho config path for reading (instance-local or global)."""
     return resolve_config_path()
 
 
+def _local_config_path() -> Path:
+    """Return the instance-local Honcho config path for writing.
+
+    Always returns $HERMES_HOME/honcho.json so each profile/instance gets
+    its own config file.  The global ~/.honcho/config.json is only used as
+    a read fallback (via resolve_config_path) for cross-app interop.
+    """
+    return get_hermes_home() / "honcho.json"
+
+
 def _read_config() -> dict:
     path = _config_path()
     if path.exists():
@@ -31,7 +42,7 @@ def _read_config() -> dict:
 
 
 def _write_config(cfg: dict, path: Path | None = None) -> None:
-    path = path or _config_path()
+    path = path or _local_config_path()
     path.parent.mkdir(parents=True, exist_ok=True)
     path.write_text(
         json.dumps(cfg, indent=2, ensure_ascii=False) + "\n",
@@ -95,13 +106,13 @@ def cmd_setup(args) -> None:
     """Interactive Honcho setup wizard."""
     cfg = _read_config()
 
-    active_path = _config_path()
+    write_path = _local_config_path()
+    read_path = _config_path()
     print("\nHoncho memory setup\n" + "─" * 40)
     print("  Honcho gives Hermes persistent cross-session memory.")
-    if active_path != GLOBAL_CONFIG_PATH:
-        print(f"  Instance config: {active_path}")
-    else:
-        print("  Config is shared with other hosts at ~/.honcho/config.json")
+    print(f"  Config: {write_path}")
+    if read_path != write_path and read_path.exists():
+        print(f"  (seeding from existing config at {read_path})")
     print()
 
     if not _ensure_sdk_installed():
@@ -189,7 +200,7 @@ def cmd_setup(args) -> None:
     hermes_host.setdefault("saveMessages", True)
 
     _write_config(cfg)
-    print(f"\n  Config written to {active_path}")
+    print(f"\n  Config written to {write_path}")
 
     # Test connection
     print("  Testing connection... ", end="", flush=True)
@@ -237,6 +248,7 @@ def cmd_status(args) -> None:
     cfg = _read_config()
 
     active_path = _config_path()
+    write_path = _local_config_path()
 
     if not cfg:
         print(f"  No Honcho config found at {active_path}")
@@ -259,6 +271,8 @@ def cmd_status(args) -> None:
     print(f"  Workspace:      {hcfg.workspace_id}")
     print(f"  Host:           {hcfg.host}")
     print(f"  Config path:    {active_path}")
+    if write_path != active_path:
+        print(f"  Write path:     {write_path}  (instance-local)")
     print(f"  AI peer:        {hcfg.ai_peer}")
     print(f"  User peer:      {hcfg.peer_name or 'not set'}")
     print(f"  Session key:    {hcfg.resolve_session_name()}")

tests/honcho_integration/test_config_isolation.py

@@ -0,0 +1,190 @@
+"""Tests for Honcho config profile isolation.
+
+Verifies that each Hermes profile writes to its own instance-local
+honcho.json ($HERMES_HOME/honcho.json) rather than the shared global
+~/.honcho/config.json.
+"""
+
+import json
+import os
+from pathlib import Path
+from unittest.mock import patch
+
+import pytest
+
+from honcho_integration.cli import (
+    _config_path,
+    _local_config_path,
+    _read_config,
+    _write_config,
+)
+
+
+@pytest.fixture
+def isolated_home(tmp_path, monkeypatch):
+    """Create an isolated HERMES_HOME + real home for testing."""
+    hermes_home = tmp_path / "profile_a"
+    hermes_home.mkdir()
+    global_dir = tmp_path / "home" / ".honcho"
+    global_dir.mkdir(parents=True)
+    global_config = global_dir / "config.json"
+
+    monkeypatch.setenv("HERMES_HOME", str(hermes_home))
+    monkeypatch.setattr(Path, "home", staticmethod(lambda: tmp_path / "home"))
+    # GLOBAL_CONFIG_PATH is a module-level constant cached at import time,
+    # so we must patch it in both the defining module and the importing module.
+    import honcho_integration.client as _client_mod
+    import honcho_integration.cli as _cli_mod
+    monkeypatch.setattr(_client_mod, "GLOBAL_CONFIG_PATH", global_config)
+    monkeypatch.setattr(_cli_mod, "GLOBAL_CONFIG_PATH", global_config)
+
+    return {
+        "hermes_home": hermes_home,
+        "global_config": global_config,
+        "local_config": hermes_home / "honcho.json",
+    }
+
+
+class TestLocalConfigPath:
+    """_local_config_path always returns $HERMES_HOME/honcho.json."""
+
+    def test_returns_hermes_home_path(self, isolated_home):
+        assert _local_config_path() == isolated_home["local_config"]
+
+    def test_differs_from_global(self, isolated_home):
+        from honcho_integration.client import GLOBAL_CONFIG_PATH
+        assert _local_config_path() != GLOBAL_CONFIG_PATH
+
+
+class TestWriteConfigIsolation:
+    """_write_config defaults to the instance-local path."""
+
+    def test_write_creates_local_file(self, isolated_home):
+        cfg = {"apiKey": "test-key", "hosts": {"hermes": {"enabled": True}}}
+        _write_config(cfg)
+
+        assert isolated_home["local_config"].exists()
+        written = json.loads(isolated_home["local_config"].read_text())
+        assert written["apiKey"] == "test-key"
+
+    def test_write_does_not_touch_global(self, isolated_home):
+        # Pre-populate global config
+        isolated_home["global_config"].write_text(
+            json.dumps({"apiKey": "global-key"})
+        )
+
+        cfg = {"apiKey": "profile-key"}
+        _write_config(cfg)
+
+        # Global should be untouched
+        global_data = json.loads(isolated_home["global_config"].read_text())
+        assert global_data["apiKey"] == "global-key"
+
+        # Local should have the new value
+        local_data = json.loads(isolated_home["local_config"].read_text())
+        assert local_data["apiKey"] == "profile-key"
+
+    def test_explicit_path_override_still_works(self, isolated_home):
+        custom = isolated_home["hermes_home"] / "custom.json"
+        _write_config({"custom": True}, path=custom)
+        assert custom.exists()
+        assert not isolated_home["local_config"].exists()
+
+
+class TestReadConfigFallback:
+    """_read_config falls back to global when no local file exists."""
+
+    def test_reads_local_when_exists(self, isolated_home):
+        isolated_home["local_config"].write_text(
+            json.dumps({"source": "local"})
+        )
+        cfg = _read_config()
+        assert cfg["source"] == "local"
+
+    def test_falls_back_to_global(self, isolated_home):
+        isolated_home["global_config"].write_text(
+            json.dumps({"source": "global"})
+        )
+        # No local file exists
+        assert not isolated_home["local_config"].exists()
+        cfg = _read_config()
+        assert cfg["source"] == "global"
+
+    def test_local_takes_priority_over_global(self, isolated_home):
+        isolated_home["local_config"].write_text(
+            json.dumps({"source": "local"})
+        )
+        isolated_home["global_config"].write_text(
+            json.dumps({"source": "global"})
+        )
+        cfg = _read_config()
+        assert cfg["source"] == "local"
+
+
+class TestMultiProfileIsolation:
+    """Two profiles writing config don't interfere with each other."""
+
+    def test_two_profiles_get_separate_configs(self, tmp_path, monkeypatch):
+        home = tmp_path / "home"
+        home.mkdir()
+        monkeypatch.setattr(Path, "home", staticmethod(lambda: home))
+
+        profile_a = tmp_path / "profile_a"
+        profile_b = tmp_path / "profile_b"
+        profile_a.mkdir()
+        profile_b.mkdir()
+
+        # Profile A writes its config
+        monkeypatch.setenv("HERMES_HOME", str(profile_a))
+        _write_config({"apiKey": "key-a", "hosts": {"hermes": {"peerName": "alice"}}})
+
+        # Profile B writes its config
+        monkeypatch.setenv("HERMES_HOME", str(profile_b))
+        _write_config({"apiKey": "key-b", "hosts": {"hermes": {"peerName": "bob"}}})
+
+        # Verify isolation
+        a_data = json.loads((profile_a / "honcho.json").read_text())
+        b_data = json.loads((profile_b / "honcho.json").read_text())
+
+        assert a_data["hosts"]["hermes"]["peerName"] == "alice"
+        assert b_data["hosts"]["hermes"]["peerName"] == "bob"
+
+    def test_first_setup_seeds_from_global(self, tmp_path, monkeypatch):
+        """First setup reads global config, writes to local."""
+        home = tmp_path / "home"
+        global_dir = home / ".honcho"
+        global_dir.mkdir(parents=True)
+        monkeypatch.setattr(Path, "home", staticmethod(lambda: home))
+        import honcho_integration.client as _client_mod
+        import honcho_integration.cli as _cli_mod
+        global_cfg_path = global_dir / "config.json"
+        monkeypatch.setattr(_client_mod, "GLOBAL_CONFIG_PATH", global_cfg_path)
+        monkeypatch.setattr(_cli_mod, "GLOBAL_CONFIG_PATH", global_cfg_path)
+
+        # Existing global config
+        global_config = global_dir / "config.json"
+        global_config.write_text(json.dumps({
+            "apiKey": "shared-key",
+            "hosts": {"hermes": {"workspace": "shared-ws"}},
+        }))
+
+        profile = tmp_path / "new_profile"
+        profile.mkdir()
+        monkeypatch.setenv("HERMES_HOME", str(profile))
+
+        # Read seeds from global
+        cfg = _read_config()
+        assert cfg["apiKey"] == "shared-key"
+
+        # Modify and write goes to local
+        cfg["hosts"]["hermes"]["peerName"] = "new-user"
+        _write_config(cfg)
+
+        local_config = profile / "honcho.json"
+        assert local_config.exists()
+        local_data = json.loads(local_config.read_text())
+        assert local_data["hosts"]["hermes"]["peerName"] == "new-user"
+
+        # Global unchanged
+        global_data = json.loads(global_config.read_text())
+        assert "peerName" not in global_data["hosts"]["hermes"]