diff --git a/.github/workflows/eval.yml b/.github/workflows/eval.yml
new file mode 100644
index 0000000..3915feb
--- /dev/null
+++ b/.github/workflows/eval.yml
@@ -0,0 +1,34 @@
+name: eval
+
+on:
+  pull_request:
+
+jobs:
+  eval:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0 # v7.0.0
+      - uses: actions/setup-node@48b55a011bda9f5d6aeb4c2d9c7362e8dae4041e # v6.4.0
+        with:
+          node-version: 22
+
+      - name: Install vally
+        run: npm install -g @microsoft/vally-cli@0.6.0
+
+      - name: Install copilot CLI
+        run: npm install -g @github/copilot@1.0.65
+
+      - name: Lint eval specs
+        run: vally lint --eval-spec evals
+
+      - name: Run evals
+        env:
+          COPILOT_GITHUB_TOKEN: ${{ secrets.COPILOT_GITHUB_TOKEN }}
+        run: vally eval --suite pr --output-dir vally-results --junit
+
+      - name: Upload eval results
+        if: always()
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a # v7.0.1
+        with:
+          name: vally-results
+          path: vally-results
diff --git a/.vally.yaml b/.vally.yaml
new file mode 100644
index 0000000..afc1f9d
--- /dev/null
+++ b/.vally.yaml
@@ -0,0 +1,9 @@
+paths:
+  evals: evals
+
+suites:
+  pr:
+    description: Run all plugin skill evals for pull requests
+    evals:
+      - evals/linting/eval.yaml
+      - evals/security/eval.yaml
diff --git a/evals/linting/eval.yaml b/evals/linting/eval.yaml
new file mode 100644
index 0000000..08b91bf
--- /dev/null
+++ b/evals/linting/eval.yaml
@@ -0,0 +1,63 @@
+name: linting skills evals
+version: 1
+description: Evaluates the linting plugin skills against representative file fixes
+
+defaults:
+  runs: 1
+  timeout: 5m
+
+stimuli:
+  - name: check-spelling-fixes-typos-and-updates-dictionary
+    prompt: |
+      Check spelling in docs/spelling.md and fix any issues you find.
+    environment:
+      skills:
+        - ../../plugins/linting/skills/check-spelling
+      files:
+        - src: ./fixtures/check-spelling/input.md
+          dest: docs/spelling.md
+    constraints:
+      expect_skills:
+        - check-spelling
+    graders:
+      - type: file-exists
+        config:
+          path: .cspell.json
+      - type: file-matches
+        config:
+          path: .cspell.json
+          pattern: 'copilotcliword'
+      - type: file-not-matches
+        config:
+          path: docs/spelling.md
+          pattern: '(?i)\\bteh\\b'
+      - type: file-matches
+        config:
+          path: docs/spelling.md
+          pattern: 'contains the typo that should be corrected[.]'
+
+  - name: lint-markdown-fixes-bullet-style
+    prompt: |
+      Lint docs/bullets.md and fix any markdown issues you find.
+    environment:
+      skills:
+        - ../../plugins/linting/skills/lint-markdown
+      files:
+        - src: ./fixtures/lint-markdown/input.md
+          dest: docs/bullets.md
+    constraints:
+      expect_skills:
+        - lint-markdown
+    graders:
+      - type: file-not-matches
+        config:
+          path: docs/bullets.md
+          pattern: '(?m)^\\* '
+      - type: file-matches
+        config:
+          path: docs/bullets.md
+          pattern: '(?m)^- first item$'
+      - type: file-matches
+        config:
+          path: docs/bullets.md
+          pattern: '(?m)^- second item that uses the wrong bullet style$'
diff --git a/evals/linting/fixtures/check-spelling/input.md b/evals/linting/fixtures/check-spelling/input.md
new file mode 100644
index 0000000..de1b668
--- /dev/null
+++ b/evals/linting/fixtures/check-spelling/input.md
@@ -0,0 +1,2 @@
+This sentence contains teh typo that should be corrected.
+The project uses copilotcliword in docs and it should be treated as valid.
diff --git a/evals/linting/fixtures/lint-markdown/input.md b/evals/linting/fixtures/lint-markdown/input.md
new file mode 100644
index 0000000..aa46978
--- /dev/null
+++ b/evals/linting/fixtures/lint-markdown/input.md
@@ -0,0 +1,4 @@
+# Bullet styles
+
+- first item
+* second item that uses the wrong bullet style
diff --git a/evals/security/eval.yaml b/evals/security/eval.yaml
new file mode 100644
index 0000000..a951727
--- /dev/null
+++ b/evals/security/eval.yaml
@@ -0,0 +1,34 @@
+name: security skills evals
+version: 1
+description: Evaluates the security plugin skills against representative workflow hardening tasks
+
+defaults:
+  runs: 1
+  timeout: 5m
+
+stimuli:
+  - name: pin-github-actions-to-shas
+    prompt: |
+      Review .github/workflows/ci.yml and harden any insecure GitHub Actions references you find.
+    environment:
+      skills:
+        - ../../plugins/security/skills/pin-github-actions
+      files:
+        - src: ./fixtures/pin-github-actions/workflow.yml
+          dest: .github/workflows/ci.yml
+    constraints:
+      expect_skills:
+        - pin-github-actions
+    graders:
+      - type: file-matches
+        config:
+          path: .github/workflows/ci.yml
+          pattern: '(?m)^ *- uses: actions/checkout@[0-9a-f]{40} # v[0-9]+[.][0-9]+[.][0-9]+$'
+      - type: file-matches
+        config:
+          path: .github/workflows/ci.yml
+          pattern: '(?m)^ *- uses: actions/setup-node@[0-9a-f]{40} # v[0-9]+[.][0-9]+[.][0-9]+$'
+      - type: file-not-matches
+        config:
+          path: .github/workflows/ci.yml
+          pattern: '(?m)uses:\\s+[^\\n]+@v[0-9]+'
diff --git a/evals/security/fixtures/pin-github-actions/workflow.yml b/evals/security/fixtures/pin-github-actions/workflow.yml
new file mode 100644
index 0000000..792c940
--- /dev/null
+++ b/evals/security/fixtures/pin-github-actions/workflow.yml
@@ -0,0 +1,14 @@
+name: CI
+
+on:
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: 22
+      - run: npm test