diff --git a/container_guts/client/__init__.py b/container_guts/client/__init__.py
index dbd5e86..3611b24 100644
--- a/container_guts/client/__init__.py
+++ b/container_guts/client/__init__.py
@@ -63,12 +63,6 @@ def get_parser():
         description="take a diff of your container against a guts database.",
         formatter_class=argparse.RawTextHelpFormatter,
     )
-    diff.add_argument(
-        "--db",
-        "--database",
-        help="Database root (of json files) to use, either filesystem or git URL to clone",
-        dest="database",
-    )
     similar = subparsers.add_parser(
         "similar",
         description="calculate similarity of your container against a guts database.",
diff --git a/docs/getting_started/user-guide.rst b/docs/getting_started/user-guide.rst
index 190d02f..97d15ab 100644
--- a/docs/getting_started/user-guide.rst
+++ b/docs/getting_started/user-guide.rst
@@ -48,12 +48,24 @@ Or to get fs and paths:
 
 This generic "manifest" command is the main entrypoint to extract guts.
 
+-------
+Similar
+-------
+
+This command calculates a similarity comparison between your container and the database
+of base images we maintain with shpc. We do this based on filesystem paths. We first remove
+all paths that are unique to your image, and then with what is left, we calculate the intersection
+over the total filesystem paths left in your image, which is saying "The percentage of non-unique
+paths that are shared between your image and the contender base."
+
+.. code-block:: console
+
+    $ guts similar vanessa/salad
+
 ----
 Diff
 ----
 
-**under development**
-
 A diff will take your container and compares it against a set of base images,
 and only reveals the diff output (the executables in PATH that are special
 to your container). If you don't provide a database (repository or path
@@ -63,7 +75,6 @@ on the filesystem) we use the default at ``singularityhub/shpc-guts``.
 
     $ guts diff vanessa/salad
 
-Note that this command is not officially added yet!
 
 GitHub Action
 -------------