diff --git a/.github/workflows/workflow.yml b/.github/workflows/workflow.yml
index 5a5b488..204ab71 100644
--- a/.github/workflows/workflow.yml
+++ b/.github/workflows/workflow.yml
@@ -1,5 +1,14 @@
 name: "Workflow"
-on: ["push"]
+on:
+  push:
+  workflow_dispatch:
+    inputs:
+      BASE_MANUAL:
+        description: "The base SHA"
+        required: true
+      HEAD_MANUAL:
+        description: "The head SHA"
+        required: false
 jobs:
   build:
     runs-on: "ubuntu-latest"
@@ -8,5 +17,10 @@ jobs:
       - name: "TODO to Issue"
         uses: "alstr/todo-to-issue-action@master"
         id: "todo"
+        env:
+          BASE_MANUAL:
+            ${{ inputs.BASE_MANUAL }}
+          HEAD_MANUAL:
+            ${{ inputs.HEAD_MANUAL }}
         with:
           PROJECTS_SECRET: ${{ secrets.PROJECTS_SECRET }}
diff --git a/main.py b/main.py
index 29baf69..0b472b8 100644
--- a/main.py
+++ b/main.py
@@ -50,7 +50,7 @@ class GitHubClient(object):
         self.repo = os.getenv('INPUT_REPO')
         self.before = os.getenv('INPUT_BEFORE')
         self.sha = os.getenv('INPUT_SHA')
-        self.commits = json.loads(os.getenv('INPUT_COMMITS'))
+        self.commits = json.loads(os.getenv('INPUT_COMMITS')) or []
         self.diff_url = os.getenv('INPUT_DIFF_URL')
         self.token = os.getenv('INPUT_TOKEN')
         self.issues_url = f'{self.repos_url}{self.repo}/issues'
@@ -646,6 +646,14 @@ class TodoParser(object):
 if __name__ == "__main__":
     # Create a basic client for communicating with GitHub, automatically initialised with environment variables.
     client = GitHubClient()
+    base_manual = os.getenv('BASE_MANUAL')
+    head_manual = os.getenv('HEAD_MANUAL')
+    if base_manual and head_manual:
+        print(f'Manually comparing {base_manual}...{head_manual}')
+        client.diff_url = f'{client.repos_url}{client.repo}/compare/{base_manual}...{head_manual}'
+    elif base_manual:
+        print(f'Manual checking {base_manual}')
+        client.diff_url = f'{client.repos_url}{client.repo}/commits/{base_manual}'
     if client.diff_url or len(client.commits) != 0:
         # Get the diff from the last pushed commit.
         last_diff = StringIO(client.get_last_diff())