diff --git a/lexicons/embed/commit.json b/lexicons/embed/commit.json
index 98dcf2ca2..c6892a2f9 100644
--- a/lexicons/embed/commit.json
+++ b/lexicons/embed/commit.json
@@ -10,7 +10,7 @@
       ],
       "properties": {
         "repo": { "type": "string", "format": "did" },
-        "commit": { "type": "union", "refs": ["sh.tangled.git.oid"] }
+        "commit": { "type": "ref", "ref": "sh.tangled.git.oid" }
       }
     },
     "view": {
diff --git a/lexicons/org/tangled/embed/commit.json b/lexicons/org/tangled/embed/commit.json
index b9184ca4d..157edb8bc 100644
--- a/lexicons/org/tangled/embed/commit.json
+++ b/lexicons/org/tangled/embed/commit.json
@@ -10,7 +10,7 @@
       ],
       "properties": {
         "repo": { "type": "string", "format": "did" },
-        "commit": { "type": "ref", "ref": "org.tangled.git.object" }
+        "commit": { "type": "ref", "ref": "org.tangled.git.oid" }
       }
     }
   }
diff --git a/lexicons/org/tangled/embed/unspecced/file.json b/lexicons/org/tangled/embed/unspecced/file.json
index 413d6e8a8..897385e8e 100644
--- a/lexicons/org/tangled/embed/unspecced/file.json
+++ b/lexicons/org/tangled/embed/unspecced/file.json
@@ -11,7 +11,7 @@
       ],
       "properties": {
         "repo": { "type": "string", "format": "did" },
-        "commit": { "type": "ref", "ref": "org.tangled.git.object" },
+        "commit": { "type": "ref", "ref": "org.tangled.git.oid" },
         "path": { "type": "string" }
       }
     }
diff --git a/lexicons/org/tangled/git/object.json b/lexicons/org/tangled/git/object.json
deleted file mode 100644
index 775b0bf4f..000000000
--- a/lexicons/org/tangled/git/object.json
+++ /dev/null
@@ -1,25 +0,0 @@
-{
-  "lexicon": 1,
-  "id": "org.tangled.git.object",
-  "description": "Git object reference similar to concrete `blob` type. This is not same as 'git reference'.",
-  "defs": {
-    "main": {
-      "type": "object",
-      "required": ["oid", "kind", "size"],
-      "properties": {
-        "oid": {
-          "type": "string",
-          "minLength": 64,
-          "maxLength": 64
-        },
-        "kind": {
-          "type": "string",
-          "enum": ["blob", "commit", "tag", "tree"]
-        },
-        "size": {
-          "type": "integer"
-        }
-      }
-    }
-  }
-}
diff --git a/lexicons/org/tangled/git/oid.json b/lexicons/org/tangled/git/oid.json
new file mode 100644
index 000000000..d131b6561
--- /dev/null
+++ b/lexicons/org/tangled/git/oid.json
@@ -0,0 +1,18 @@
+{
+  "lexicon": 1,
+  "id": "org.tangled.git.oid",
+  "description": "Git object-id similar to concrete `cid-link` type.",
+  "defs": {
+    "main": {
+      "type": "object",
+      "required": ["oid"],
+      "properties": {
+        "oid": {
+          "type": "string",
+          "minLength": 40,
+          "maxLength": 64
+        }
+      }
+    }
+  }
+}
diff --git a/lexicons/org/tangled/review/patch.json b/lexicons/org/tangled/review/patch.json
index 38dfc431b..f8839b5e4 100644
--- a/lexicons/org/tangled/review/patch.json
+++ b/lexicons/org/tangled/review/patch.json
@@ -20,8 +20,8 @@
             "format": "record-key",
             "description": "ticket-id"
           },
-          "base": { "type": "ref", "ref": "org.tangled.git.object" },
-          "head": { "type": "ref", "ref": "org.tangled.git.object" },
+          "base": { "type": "ref", "ref": "org.tangled.git.oid" },
+          "head": { "type": "ref", "ref": "org.tangled.git.oid" },
           "createdAt": { "type": "string", "format": "datetime" }
         }
       }
diff --git a/lexicons/org/tangled/review/unspecced/round.json b/lexicons/org/tangled/review/unspecced/round.json
index 26b0d0caf..6b2fe4a36 100644
--- a/lexicons/org/tangled/review/unspecced/round.json
+++ b/lexicons/org/tangled/review/unspecced/round.json
@@ -22,7 +22,7 @@
           },
           "commit": {
             "type": "ref",
-            "ref": "org.tangled.git.object",
+            "ref": "org.tangled.git.oid",
             "description": "ID of commit that is getting reviewed."
           },
           "state": {