diff --git a/CHANGELOG.md b/CHANGELOG.md
index 1b750ee4..85244db6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,10 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Breaking Changes
+
+- Local configuration directory renamed from `~/.galileo` to `~/.splunk`. The override environment variable is now `SPLUNK_AO_HOME_DIR` (previously `GALILEO_HOME_DIR`).
+
 ## [0.2.1] - 2026-08-07
 
 ### Fixed
diff --git a/splunk-ao-migration-tool/README.md b/splunk-ao-migration-tool/README.md
index 250c0f95..88d800b7 100644
--- a/splunk-ao-migration-tool/README.md
+++ b/splunk-ao-migration-tool/README.md
@@ -280,6 +280,7 @@ All `GALILEO_*` environment variables are renamed to `SPLUNK_AO_*`. This is a **
 | `GALILEO_DEFAULT_SCORER_MODEL` | `SPLUNK_AO_DEFAULT_SCORER_MODEL` |
 | `GALILEO_DEFAULT_SCORER_JUDGES` | `SPLUNK_AO_DEFAULT_SCORER_JUDGES` |
 | `GALILEO_CODE_VALIDATION_*` (4 vars) | `SPLUNK_AO_CODE_VALIDATION_*` |
+| `GALILEO_HOME_DIR` | `SPLUNK_AO_HOME_DIR` |
 
 ¹ `GALILEO_API_URL` was not a user-facing env var in `galileo-python` — it was an implicit Pydantic settings field on `galileo-core`'s `GalileoConfig`. `SPLUNK_AO_API_URL` is its effective rename and is explicitly bridged in `SplunkAOConfig._bridge_env_vars()`.
 
@@ -340,16 +341,19 @@ The `GalileoScorers` enum has been removed entirely. Migrate to `SplunkAOEvaluat
 + scorer = SplunkAOEvaluators.completeness
 ```
 
-### 5.3 On-Disk Config File
+### 5.3 On-Disk Config File and Directory
 
 On logout or reset, `splunk-ao-python` writes a non-secret debug snapshot to
-`~/.galileo/splunk-ao-config.json`. The directory `~/.galileo/` is inherited
-from `galileo-core` and unchanged.
+`~/.splunk/splunk-ao-config.json`. Both the directory (`~/.splunk/`, was
+`~/.galileo/`) and the filename (`splunk-ao-config.json`, was
+`galileo-python-config.json`) have changed.
 
 This file is never read back and has no effect on authentication or config
 resolution. If you have an existing `~/.galileo/galileo-python-config.json`
 from `galileo-python`, it can be deleted at leisure or simply ignored.
 
+The directory can be overridden via `SPLUNK_AO_HOME_DIR` (previously `GALILEO_HOME_DIR`).
+
 ---
 
 ## 6. HTTP Tracing Headers
diff --git a/src/splunk_ao/config.py b/src/splunk_ao/config.py
index bf002819..c145e250 100644
--- a/src/splunk_ao/config.py
+++ b/src/splunk_ao/config.py
@@ -2,10 +2,11 @@
 # We need to ignore syntax errors until https://github.com/python/mypy/issues/17535 is resolved.
 import os
 from collections.abc import Iterator
-from typing import Any, ClassVar, Optional
+from pathlib import Path
+from typing import Any, ClassVar, Optional, Union
 
 from httpx import Response
-from pydantic import SecretStr, ValidationInfo, field_validator, model_validator
+from pydantic import Field, SecretStr, ValidationInfo, field_validator, model_validator
 from pydantic_core import Url
 
 from galileo_core.constants.request_method import RequestMethod
@@ -64,18 +65,35 @@ def stream_request(self, method: RequestMethod, path: str, *args: Any, **kwargs:
     ("SPLUNK_AO_USERNAME", "GALILEO_USERNAME"),
     ("SPLUNK_AO_PASSWORD", "GALILEO_PASSWORD"),
     ("SPLUNK_AO_MODE", "GALILEO_MODE"),
+    ("SPLUNK_AO_HOME_DIR", "GALILEO_HOME_DIR"),
 ]
 
 
 class SplunkAOConfig(GalileoConfig):
     """Configure authentication and endpoints for standalone and O11y deployments."""
 
+    home_dir: Path = Field(
+        default=Path.home() / ".splunk",
+        validate_default=True,
+        description="Home directory for Splunk AO.",
+        exclude=True,
+    )
     # Config file for this project.
     config_filename: str = "splunk-ao-config.json"
     console_url: Url = DEFAULT_CONSOLE_URL
 
     _instance: ClassVar[Optional["SplunkAOConfig"]] = None
 
+    @field_validator("home_dir", mode="before")
+    @classmethod
+    def set_home_dir(cls, value: Union[str, Path]) -> Path:
+        value = Path(value)
+        if not value.exists():
+            value.mkdir(parents=True, exist_ok=True)
+        if not value.is_dir():
+            raise ValueError(f"`SPLUNK_AO_HOME_DIR` {value} is not a directory.")
+        return value
+
     def reset(self) -> None:
         # Remove any GALILEO_* keys the bridge injected into os.environ so that
         # the next get() call re-bridges from scratch with whatever SPLUNK_AO_*