fix(memory): migration checks provider presence in the home being migrated

hermes_cli/memory_provider_migration.py

@@ -32,10 +32,17 @@ def configured_provider(home: Path) -> str:
     return str(memory.get("provider") or "").strip()
 
 
-def provider_present(name: str) -> bool:
-    """True when the provider resolves anywhere Hermes looks (bundled, user dir, entry point)."""
+def provider_present(name: str, home: Path) -> bool:
+    """True when the provider resolves anywhere Hermes looks for *home* (bundled, that home's user
+    plugins, entry point). The lookup reads the active home, so it is bound explicitly: the update
+    hook walks several profile homes from one process."""
     from plugins.memory import find_provider_dir
-    return find_provider_dir(name) is not None
+    from hermes_constants import reset_hermes_home_override, set_hermes_home_override
+    token = set_hermes_home_override(home)
+    try:
+        return find_provider_dir(name) is not None
+    finally:
+        reset_hermes_home_override(token)
 
 
 def catalog_source(name: str) -> Optional[str]:
@@ -53,7 +60,7 @@ def migrate_home(home: Path, *, install: Callable[[str], dict], say: Callable[[s
     update or the agent down with it.
     """
     name = configured_provider(home)
-    if not name or provider_present(name):
+    if not name or provider_present(name, home):
         return None
     if catalog_source(name) is None:
         say(f"  ⚠ Memory provider '{name}' is configured but not installed and not in the plugin catalog. "

tests/hermes_cli/test_memory_provider_migration.py

@@ -12,7 +12,7 @@ from hermes_cli import memory_provider_migration as mig
 def home(tmp_path, monkeypatch):
     monkeypatch.setenv("HERMES_HOME", str(tmp_path))
     (tmp_path / "config.yaml").write_text("memory:\n  provider: honcho\n  honcho:\n    workspace: keep-me\n")
-    monkeypatch.setattr(mig, "provider_present", lambda name: (tmp_path / "plugins" / name).is_dir())
+    monkeypatch.setattr(mig, "provider_present", lambda name, home: (home / "plugins" / name).is_dir())
     return tmp_path
 
 
@@ -35,6 +35,22 @@ def test_missing_provider_installs_its_catalog_plugin_and_keeps_config(home, mon
     assert calls == ["honcho"]
 
 
+def test_presence_is_checked_in_the_home_being_migrated(tmp_path, monkeypatch):
+    """The update hook walks several profile homes from one process; a provider installed in profile B
+    must count as present for B even when the process-level home (A) lacks it. Real lookup, no mock."""
+    a, b = tmp_path / "a", tmp_path / "b"
+    for h in (a, b):
+        h.mkdir(); (h / "config.yaml").write_text("memory:\n  provider: twin\n")
+    (b / "plugins" / "twin").mkdir(parents=True)
+    (b / "plugins" / "twin" / "__init__.py").write_text("class Twin(MemoryProvider): ...\n")
+    monkeypatch.setenv("HERMES_HOME", str(a))
+    monkeypatch.setattr(mig, "catalog_source", lambda name: name)
+    installs: list[Path] = []
+    assert mig.migrate_home(b, install=lambda n: installs.append(b) or {"ok": True}, say=lambda s: None) is None
+    assert installs == []
+    assert mig.migrate_home(a, install=lambda n: installs.append(a) or {"ok": True}, say=lambda s: None) == "twin"
+
+
 def test_provider_unknown_to_catalog_is_reported_not_installed(home, monkeypatch):
     monkeypatch.setattr(mig, "catalog_source", lambda name: None)
     said: list[str] = []