diff --git a/.claude/rules/ci.md b/.claude/rules/ci.md
index 5f470af9..195b3d31 100644
--- a/.claude/rules/ci.md
+++ b/.claude/rules/ci.md
@@ -8,6 +8,6 @@ paths:
 - `main` + feature branches, CI runs on non-main branches only
 - **lint.yml**: `pnpm check` — **test.yml**: `pnpm test:unit` — **build.yml**: `pnpm build` + upload `.next/`
 - **update-msw.yml**: Auto-update MSW worker (Renovate bot only)
-- Shared setup: ubuntu-24.04, 10min timeout, `pnpm/action-setup@v5`, Node.js from `.tool-versions`, copies `.env.development` to `.env.local`
+- Shared setup: ubuntu-24.04, 10min timeout, `pnpm/action-setup@v6`, Node.js from `mise.toml`, copies `.env.development` to `.env.local`
 - `upload-artifact` requires `include-hidden-files: true` for `.next/`
 - Action versions pinned by commit SHA
diff --git a/.github/actions/setup/action.yml b/.github/actions/setup/action.yml
index 6079ec94..23731c3a 100644
--- a/.github/actions/setup/action.yml
+++ b/.github/actions/setup/action.yml
@@ -10,13 +10,19 @@ inputs:
 runs:
   using: "composite"
   steps:
+    - name: Read Node version from mise.toml
+      id: versions
+      shell: bash
+      run: |
+        echo "node=$(grep -E '^node\s*=' mise.toml | sed 's/.*=\s*"\(.*\)"/\1/')" >> "$GITHUB_OUTPUT"
+
     - name: Install pnpm
       uses: pnpm/action-setup@08c4be7e2e672a47d11bd04269e27e5f3e8529cb # v6
 
     - name: Setup Node.js
       uses: actions/setup-node@53b83947a5a98c8d113130e565377fae1a50d02f # v6
       with:
-        node-version-file: ".tool-versions"
+        node-version: ${{ steps.versions.outputs.node }}
         cache: "pnpm"
 
     - name: Install dependencies
diff --git a/.tool-versions b/.tool-versions
deleted file mode 100644
index 3dc2f9ea..00000000
--- a/.tool-versions
+++ /dev/null
@@ -1,4 +0,0 @@
-actionlint latest
-nodejs     24.14.1
-pnpm       10.33.0
-zizmor     latest
diff --git a/mise.toml b/mise.toml
new file mode 100644
index 00000000..93e2137f
--- /dev/null
+++ b/mise.toml
@@ -0,0 +1,5 @@
+[tools]
+actionlint = "1.7.12"
+node = "24.14.1"
+pnpm = "10.33.0"
+zizmor = "1.24.1"