diff --git a/.github/workflows/auto-generate.yml b/.github/workflows/auto-generate.yml
new file mode 100644
index 0000000..9ef5f0e
--- /dev/null
+++ b/.github/workflows/auto-generate.yml
@@ -0,0 +1,68 @@
+# Copyright 2026 UCP Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+name: Auto-generate Models
+
+on:
+  repository_dispatch:
+    types: [spec-release]
+  workflow_dispatch:
+    inputs:
+      version:
+        description: 'Version to release (e.g. v1.2.3)'
+        required: true
+
+jobs:
+  generate:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout SDK
+        uses: actions/checkout@v4
+
+      - name: Checkout Specification
+        uses: actions/checkout@v4
+        with:
+          repository: Universal-Commerce-Protocol/ucp
+          ref: ${{ github.event.client_payload.version || github.event.inputs.version }}
+          path: ucp-repo
+          token: ${{ secrets.CROSS_REPO_READ_PAT }}
+
+      - name: Set up Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.11'
+
+      - name: Install uv
+        run: curl -LsSf https://astral.sh/uv/install.sh | sh
+
+      - name: Generate Models
+        run: |
+          export SCHEMA_DIR="ucp-repo/source/schemas"
+          ./generate_models.sh
+
+      - name: Update version in pyproject.toml
+        run: |
+          TAG_VERSION="${{ github.event.client_payload.version || github.event.inputs.version }}"
+          PY_VERSION=${TAG_VERSION#v}
+          sed -i "s/^version = ".*"/version = "$PY_VERSION"/" pyproject.toml
+
+      - name: Create Pull Request
+        uses: peter-evans/create-pull-request@v6
+        with:
+          token: ${{ secrets.CROSS_REPO_READ_PAT }}
+          commit-message: "chore: update models to ${{ github.event.client_payload.version || github.event.inputs.version }}"
+          title: "Update models to ${{ github.event.client_payload.version || github.event.inputs.version }}"
+          body: "This PR updates the SDK models based on the latest specification release ${{ github.event.client_payload.version || github.event.inputs.version }}."
+          branch: "auto-update-models-${{ github.event.client_payload.version || github.event.inputs.version }}"
+          base: main
\ No newline at end of file
diff --git a/generate_models.sh b/generate_models.sh
index 26afb35..60aa330 100755
--- a/generate_models.sh
+++ b/generate_models.sh
@@ -1,4 +1,5 @@
 #!/bin/bash
+# Copyright 2026 UCP Authors
 # Generate Pydantic models from UCP JSON Schemas
 
 # Ensure we are in the script's directory
@@ -8,7 +9,7 @@ cd "$(dirname "$0")" || exit
 OUTPUT_DIR="src/ucp_sdk/models"
 
 # Schema directory (relative to this script)
-SCHEMA_DIR="../../spec/"
+SCHEMA_DIR="${SCHEMA_DIR:-../../spec/}"
 
 echo "Generating Pydantic models from $SCHEMA_DIR..."