fix: use persistent platform-appropriate dirs instead of /tmp for vector store defaults (#4279)

Replace hardcoded /tmp/{provider} default paths with XDG-compliant persistent
directories (~/.local/share/mem0/{provider}), fixing failures on Windows,
macOS LaunchAgents, Linux systemd, and Docker. Adds MEM0_DATA_DIR env var
override, legacy /tmp data migration warning, and updates Qdrant/ChromaDB/FAISS
configs and docs to use the new defaults.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

mem0/configs/vector_stores/chroma.py

@@ -2,6 +2,8 @@ from typing import Any, ClassVar, Dict, Optional
 
 from pydantic import BaseModel, ConfigDict, Field, model_validator
 
+from mem0.vector_stores.configs import get_default_vector_store_path
+
 
 class ChromaDbConfig(BaseModel):
     try:
@@ -23,24 +25,25 @@ class ChromaDbConfig(BaseModel):
     def check_connection_config(cls, values):
         host, port, path = values.get("host"), values.get("port"), values.get("path")
         api_key, tenant = values.get("api_key"), values.get("tenant")
-        
+        default_path = get_default_vector_store_path("chroma")
+
         # Check if cloud configuration is provided
         cloud_config = bool(api_key and tenant)
-        
+
         # If cloud configuration is provided, remove any default path that might have been added
-        if cloud_config and path == "/tmp/chroma":
+        if cloud_config and path == default_path:
             values.pop("path", None)
             return values
-        
+
         # Check if local/server configuration is provided
         local_config = bool(path) or bool(host and port)
-        
+
         if not cloud_config and not local_config:
             raise ValueError("Either ChromaDB Cloud configuration (api_key, tenant) or local configuration (path or host/port) must be provided.")
-        
+
         if cloud_config and local_config:
             raise ValueError("Cannot specify both cloud configuration and local configuration. Choose one.")
-            
+
         return values
 
     @model_validator(mode="before")

mem0/configs/vector_stores/qdrant.py

@@ -2,6 +2,8 @@ from typing import Any, ClassVar, Dict, Optional
 
 from pydantic import BaseModel, ConfigDict, Field, model_validator
 
+from mem0.vector_stores.configs import get_default_vector_store_path
+
 
 class QdrantConfig(BaseModel):
     from qdrant_client import QdrantClient
@@ -13,7 +15,7 @@ class QdrantConfig(BaseModel):
     client: Optional[QdrantClient] = Field(None, description="Existing Qdrant client instance")
     host: Optional[str] = Field(None, description="Host address for Qdrant server")
     port: Optional[int] = Field(None, description="Port for Qdrant server")
-    path: Optional[str] = Field("/tmp/qdrant", description="Path for local Qdrant database")
+    path: Optional[str] = Field(default_factory=lambda: get_default_vector_store_path("qdrant"), description="Path for local Qdrant database")
     url: Optional[str] = Field(None, description="Full URL for Qdrant server")
     api_key: Optional[str] = Field(None, description="API key for Qdrant server")
     on_disk: Optional[bool] = Field(False,description="Enables persistent storage. Vectors are kept on disk (True) or in memory (False). Does not delete the local database path.")

mem0/vector_stores/configs.py

@@ -1,10 +1,33 @@
+import logging
 import os
-
 from pathlib import Path
 from typing import Dict, Optional
 
 from pydantic import BaseModel, Field, model_validator
 
+logger = logging.getLogger(__name__)
+
+
+def get_default_vector_store_path(provider: str) -> str:
+    """Return a platform-appropriate default path for a vector store provider.
+
+    Preference order: MEM0_DATA_DIR → XDG_DATA_HOME (Linux) → APPDATA (Windows) → ~/.local/share
+    """
+    mem0_data_dir = os.environ.get("MEM0_DATA_DIR")
+    if mem0_data_dir:
+        base = Path(mem0_data_dir)
+    else:
+        xdg = os.environ.get("XDG_DATA_HOME")
+        app_data = os.environ.get("APPDATA")
+        if xdg:
+            base = Path(xdg)
+        elif app_data:
+            base = Path(app_data)
+        else:
+            base = Path.home() / ".local" / "share"
+        base = base / "mem0"
+    return str(base / provider)
+
 
 class VectorStoreConfig(BaseModel):
     provider: str = Field(
@@ -64,18 +87,16 @@ class VectorStoreConfig(BaseModel):
 
         # also check if path in allowed kays for pydantic model, and whether config extra fields are allowed
         if "path" not in config and "path" in config_class.__annotations__:
-            # Use a platform-appropriate user data directory instead of /tmp, which is
-            # ephemeral on many systems and may be unwritable in service/restricted environments.
-            # Preference order: XDG_DATA_HOME (Linux) → APPDATA (Windows) → ~/.local/share
-            xdg = os.environ.get("XDG_DATA_HOME")
-            app_data = os.environ.get("APPDATA")
-            if xdg:
-                base = Path(xdg)
-            elif app_data:
-                base = Path(app_data)
-            else:
-                base = Path.home() / ".local" / "share"
-            config["path"] = str(base / "mem0" / provider)
+            config["path"] = get_default_vector_store_path(provider)
+
+            legacy_path = Path(f"/tmp/{provider}")
+            if legacy_path.exists() and any(legacy_path.iterdir()):
+                logger.warning(
+                    f"Found existing data at legacy path '{legacy_path}'. "
+                    f"mem0 now defaults to '{config['path']}'. "
+                    f"To keep using the old location, set path='/tmp/{provider}' in your config, "
+                    f"or move the data to the new path."
+                )
 
         self.config = config_class(**config)
         return self

mem0/vector_stores/faiss.py

@@ -8,6 +8,8 @@ from typing import Dict, List, Optional
 import numpy as np
 from pydantic import BaseModel
 
+from mem0.vector_stores.configs import get_default_vector_store_path
+
 import warnings
 
 try:
@@ -58,7 +60,7 @@ class FAISS(VectorStoreBase):
                 Defaults to False.
         """
         self.collection_name = collection_name
-        self.path = path or f"/tmp/faiss/{collection_name}"
+        self.path = path or f"{get_default_vector_store_path('faiss')}/{collection_name}"
         self.distance_strategy = distance_strategy
         self.normalize_L2 = normalize_L2
         self.embedding_model_dims = embedding_model_dims