diff --git a/.changeset/minor-remove-defaults-schema.md b/.changeset/minor-remove-defaults-schema.md
new file mode 100644
index 0000000000..c644095711
--- /dev/null
+++ b/.changeset/minor-remove-defaults-schema.md
@@ -0,0 +1,5 @@
+---
+"gh-aw": minor
+---
+
+Remove "defaults" section from main JSON schema
diff --git a/docs/src/content/docs/reference/frontmatter-full.md b/docs/src/content/docs/reference/frontmatter-full.md
index 79e9b91b58..04f9837747 100644
--- a/docs/src/content/docs/reference/frontmatter-full.md
+++ b/docs/src/content/docs/reference/frontmatter-full.md
@@ -620,20 +620,6 @@ permissions:
 # (optional)
 run-name: "example-value"
 
-# Default settings that will apply to all jobs in the workflow
-# (optional)
-defaults:
-  # Default shell and working directory
-  # (optional)
-  run:
-    # Default shell for run steps
-    # (optional)
-    shell: "example-value"
-
-    # Default working directory for run steps
-    # (optional)
-    working-directory: "example-value"
-
 # Groups together all the jobs that run in the workflow
 # (optional)
 jobs:
diff --git a/pkg/constants/constants.go b/pkg/constants/constants.go
index 14a10a1446..c93ea90a83 100644
--- a/pkg/constants/constants.go
+++ b/pkg/constants/constants.go
@@ -317,7 +317,7 @@ var PriorityStepFields = []string{"name", "id", "if", "run", "uses", "script", "
 
 // PriorityJobFields defines the conventional field order for GitHub Actions workflow jobs
 // Fields appear in this order first, followed by remaining fields alphabetically
-var PriorityJobFields = []string{"name", "runs-on", "needs", "if", "permissions", "environment", "concurrency", "outputs", "env", "defaults", "steps"}
+var PriorityJobFields = []string{"name", "runs-on", "needs", "if", "permissions", "environment", "concurrency", "outputs", "env", "steps"}
 
 // PriorityWorkflowFields defines the conventional field order for top-level GitHub Actions workflow frontmatter
 // Fields appear in this order first, followed by remaining fields alphabetically
diff --git a/pkg/parser/schema_test.go b/pkg/parser/schema_test.go
index 1774f6180d..18b58db2d2 100644
--- a/pkg/parser/schema_test.go
+++ b/pkg/parser/schema_test.go
@@ -723,32 +723,6 @@ func TestValidateMainWorkflowFrontmatterWithSchema(t *testing.T) {
 			},
 			wantErr: false,
 		},
-		{
-			name: "valid GitHub Actions defaults property",
-			frontmatter: map[string]any{
-				"on": "push",
-				"defaults": map[string]any{
-					"run": map[string]any{
-						"shell":             "bash",
-						"working-directory": "/app",
-					},
-				},
-			},
-			wantErr: false,
-		},
-		{
-			name: "invalid defaults with additional properties",
-			frontmatter: map[string]any{
-				"defaults": map[string]any{
-					"run": map[string]any{
-						"shell":        "bash",
-						"invalid_prop": "value",
-					},
-				},
-			},
-			wantErr:     true,
-			errContains: "additional properties 'invalid_prop' not allowed",
-		},
 		{
 			name: "valid claude engine with network permissions",
 			frontmatter: map[string]any{
diff --git a/pkg/parser/schemas/main_workflow_schema.json b/pkg/parser/schemas/main_workflow_schema.json
index a1ba9f42d2..2b82980d6d 100644
--- a/pkg/parser/schemas/main_workflow_schema.json
+++ b/pkg/parser/schemas/main_workflow_schema.json
@@ -1070,28 +1070,6 @@
       "type": "string",
       "description": "Custom name for workflow runs that appears in the GitHub Actions interface (supports GitHub expressions like ${{ github.event.issue.title }})"
     },
-    "defaults": {
-      "type": "object",
-      "description": "Default settings that will apply to all jobs in the workflow",
-      "additionalProperties": false,
-      "properties": {
-        "run": {
-          "type": "object",
-          "description": "Default shell and working directory",
-          "additionalProperties": false,
-          "properties": {
-            "shell": {
-              "type": "string",
-              "description": "Default shell for run steps"
-            },
-            "working-directory": {
-              "type": "string",
-              "description": "Default working directory for run steps"
-            }
-          }
-        }
-      }
-    },
     "jobs": {
       "type": "object",
       "description": "Groups together all the jobs that run in the workflow",
@@ -1194,9 +1172,6 @@
               "type": "string"
             }
           },
-          "defaults": {
-            "$ref": "#/properties/defaults"
-          },
           "concurrency": {
             "$ref": "#/properties/concurrency"
           }