diff --git a/doc/compiled.json b/doc/compiled.json
index b0e457e8..f1d1d0f3 100644
--- a/doc/compiled.json
+++ b/doc/compiled.json
@@ -2444,6 +2444,14 @@
                 "type": "string",
                 "example": "legacy"
               },
+              "translation_keys_sort_collation": {
+                "type": "string",
+                "example": "unicode_ci",
+                "enum": [
+                  "general_ci",
+                  "unicode_ci"
+                ]
+              },
               "job_locking_enabled": {
                 "type": "boolean",
                 "example": false
@@ -2483,6 +2491,7 @@
               "autocomplete_job_enabled": false,
               "default_encoding": "UTF-8",
               "cldr_version": "legacy",
+              "translation_keys_sort_collation": "unicode_ci",
               "job_locking_enabled": false,
               "placeholder_styles": [
                 "rails_i18n",
@@ -18168,7 +18177,11 @@
                   "translation_keys_sort_collation": {
                     "description": "(Optional) Collation used when sorting translation keys alphabetically. Defaults to `unicode_ci` when omitted.",
                     "type": "string",
-                    "example": "unicode_ci"
+                    "example": "unicode_ci",
+                    "enum": [
+                      "general_ci",
+                      "unicode_ci"
+                    ]
                   },
                   "default_encoding": {
                     "description": "(Optional) Sets the default encoding for Uploads. If you leave it empty, we will try to guess it automatically for you when you Upload a file. You can still override this value by setting the [`file_encoding`](/en/api/strings/uploads/upload-a-new-file) parameter for Uploads.",
@@ -18540,7 +18553,11 @@
                   "translation_keys_sort_collation": {
                     "description": "(Optional) Collation used when sorting translation keys alphabetically.",
                     "type": "string",
-                    "example": "unicode_ci"
+                    "example": "unicode_ci",
+                    "enum": [
+                      "general_ci",
+                      "unicode_ci"
+                    ]
                   },
                   "cldr_version": {
                     "description": "(Optional) CLDR plural-rule version used by the project. Pass `legacy` for pre-CLDR pluralization behaviour, or a CLDR version string such as `cldr48`. Also used as the default version for the ICU skeleton endpoint (`POST /icu/skeleton`) when its own `cldr_version` parameter is omitted.",
diff --git a/paths/projects/create.yaml b/paths/projects/create.yaml
index f0bcb125..2eca3a3d 100644
--- a/paths/projects/create.yaml
+++ b/paths/projects/create.yaml
@@ -203,6 +203,9 @@ requestBody:
             description: "(Optional) Collation used when sorting translation keys alphabetically. Defaults to `unicode_ci` when omitted."
             type: string
             example: unicode_ci
+            enum:
+              - "general_ci"
+              - "unicode_ci"
           default_encoding:
             description: "(Optional) Sets the default encoding for Uploads. If you leave it empty, we will try to guess it automatically for you when you Upload a file. You can still override this value by setting the [`file_encoding`](/en/api/strings/uploads/upload-a-new-file) parameter for Uploads."
             type: string
diff --git a/paths/projects/update.yaml b/paths/projects/update.yaml
index 09d0c125..c69aa570 100644
--- a/paths/projects/update.yaml
+++ b/paths/projects/update.yaml
@@ -216,6 +216,9 @@ requestBody:
             description: "(Optional) Collation used when sorting translation keys alphabetically."
             type: string
             example: unicode_ci
+            enum:
+              - "general_ci"
+              - "unicode_ci"
           cldr_version:
             description: >-
               (Optional) CLDR plural-rule version used by the project. Pass
diff --git a/schemas/project_details.yaml b/schemas/project_details.yaml
index 59bf8738..dcfa8088 100644
--- a/schemas/project_details.yaml
+++ b/schemas/project_details.yaml
@@ -63,6 +63,12 @@ project_details:
       cldr_version:
         type: string
         example: "legacy"
+      translation_keys_sort_collation:
+        type: string
+        example: "unicode_ci"
+        enum:
+          - "general_ci"
+          - "unicode_ci"
       job_locking_enabled:
         type: boolean
         example: false
@@ -97,6 +103,7 @@ project_details:
       autocomplete_job_enabled: false
       default_encoding: "UTF-8"
       cldr_version: "legacy"
+      translation_keys_sort_collation: "unicode_ci"
       job_locking_enabled: false
       placeholder_styles:
         - "rails_i18n"