diff --git a/.forgejo/workflows/act.yml b/.forgejo/workflows/act.yml
index 8ae625ff..206eaae9 100644
--- a/.forgejo/workflows/act.yml
+++ b/.forgejo/workflows/act.yml
@@ -53,8 +53,8 @@ jobs:
 
       - name: unit test
         run: |
-          go test -short -v ./act/container
-          go test -v ./act/artifactcache/... ./act/workflowpattern/... ./act/filecollector/... ./act/common/... ./act/jobparser ./act/model ./act/exprparser ./act/schema
+          go test -short ./act/container
+          go test ./act/artifactcache/... ./act/workflowpattern/... ./act/filecollector/... ./act/common/... ./act/jobparser ./act/model ./act/exprparser ./act/schema
 
   integration:
     runs-on: lxc-bookworm
@@ -74,5 +74,5 @@ jobs:
 
       - name: integration test
         run: |
-          go test -v ./act/container
-          go test -v ./act/runner/...
+          go test ./act/container
+          go test ./act/runner/...
diff --git a/act/schema/action_schema.json b/act/schema/action_schema.json
index 9b1ac8dd..2b2a22f0 100644
--- a/act/schema/action_schema.json
+++ b/act/schema/action_schema.json
@@ -15,12 +15,18 @@
       }
     },
     "inputs": {
+      "one-of": ["null", "inputs-mapping"]
+    },
+    "inputs-mapping": {
       "mapping": {
         "loose-key-type": "non-empty-string",
         "loose-value-type": "input"
       }
     },
     "input": {
+      "one-of": ["null", "input-mapping"]
+    },
+    "input-mapping": {
       "mapping": {
         "properties": {
           "default": "input-default-context"
@@ -190,6 +196,7 @@
         "steps",
         "job",
         "runner",
+        "vars",
         "env",
         "hashFiles(1,255)"
       ],
@@ -205,6 +212,7 @@
         "steps",
         "job",
         "runner",
+        "vars",
         "env",
         "hashFiles(1,255)"
       ],
@@ -239,6 +247,7 @@
         "steps",
         "job",
         "runner",
+        "vars",
         "env",
         "always(0,0)",
         "failure(0,0)",
@@ -258,6 +267,7 @@
         "steps",
         "job",
         "runner",
+        "vars",
         "env",
         "hashFiles(1,255)"
       ],
diff --git a/act/schema/schema.go b/act/schema/schema.go
index 71f474db..d452f012 100644
--- a/act/schema/schema.go
+++ b/act/schema/schema.go
@@ -125,9 +125,10 @@ func (s *Node) checkSingleExpression(exprNode actionlint.ExprNode) error {
 		case actionlint.TokenKindInt:
 		case actionlint.TokenKindFloat:
 		case actionlint.TokenKindString:
+		case actionlint.TokenKindIdent:
 			return nil
 		default:
-			return fmt.Errorf("expressions are not allowed here")
+			return fmt.Errorf("expressions are not allowed in %v", exprNode.Token().Kind)
 		}
 	}
 
diff --git a/act/schema/schema_test.go b/act/schema/schema_test.go
index 6c3b1a8b..5941fc40 100644
--- a/act/schema/schema_test.go
+++ b/act/schema/schema_test.go
@@ -123,12 +123,17 @@ jobs:
 }
 
 func TestActionSchema(t *testing.T) {
-	var node yaml.Node
-	err := yaml.Unmarshal([]byte(`
+	for _, testCase := range []struct {
+		name   string
+		action string
+	}{
+		{
+			name: "Expressions",
+			action: `
 name: 'action name'
 author: 'action authors'
 description: |
-  action description
+  action ${{ env.SOMETHING }} description
 inputs:
   url:
     description: 'url description'
@@ -143,13 +148,41 @@ runs:
         echo "${{ github.action_path }}"
       env:
           MYVAR: ${{ vars.VARIABLE }}
-`), &node)
-	if !assert.NoError(t, err) {
-		return
+`,
+		},
+		{
+			name: "NoInputs",
+			action: `
+runs:
+  using: "composite"
+  steps:
+    - run: echo OK
+`,
+		},
+		{
+			name: "NoMappingInputs",
+			action: `
+inputs:
+  parameter1:
+  parameter2:
+runs:
+  using: "composite"
+  steps:
+    - run: echo OK
+`,
+		},
+	} {
+		t.Run(testCase.name, func(t *testing.T) {
+			var node yaml.Node
+			err := yaml.Unmarshal([]byte(testCase.action), &node)
+			if !assert.NoError(t, err) {
+				return
+			}
+			err = (&Node{
+				Definition: "action-root",
+				Schema:     GetActionSchema(),
+			}).UnmarshalYAML(&node)
+			assert.NoError(t, err)
+		})
 	}
-	err = (&Node{
-		Definition: "action-root",
-		Schema:     GetActionSchema(),
-	}).UnmarshalYAML(&node)
-	assert.NoError(t, err)
 }