Allow overriding config location with MEMGPT_CONFIG_PATH (#383)

docs/config.md

@@ -1,5 +1,5 @@
 ### Configuring the agent
-You can set agent defaults by running `memgpt configure`.
+You can set agent defaults by running `memgpt configure`, which will store config information at `~/.memgpt/config` by default.
 
 The `memgpt run` command supports the following optional flags (if set, will override config defaults):
 
@@ -13,6 +13,12 @@ The `memgpt run` command supports the following optional flags (if set, will ove
 * `--no-verify`: (bool) Bypass message verification (default=False)
 * `--yes`/`-y`: (bool) Skip confirmation prompt and use defaults (default=False)
 
+#### Updating the config location
+You can override the location of the config path by setting the enviornment variable `MEMGPT_CONFIG_PATH`:
+```
+export MEMGPT_CONFIG_PATH=/my/custom/path/config # make sure this is a file, not a directory
+```
+
 
 ### Adding Custom Personas/Humans
 You can add new human or persona definitions either by providing a file (using the `-f` flag) or text (using the `--text` flag).

memgpt/config.py

@@ -228,6 +228,8 @@ class MemGPTConfig:
             config_path = os.getenv("MEMGPT_CONFIG_PATH")
         else:
             config_path = MemGPTConfig.config_path
+
+        assert not os.path.isdir(config_path), f"Config path {config_path} cannot be set to a directory."
         return os.path.exists(config_path)
 
     @staticmethod