diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index fba2923..00e3696 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -19,10 +19,10 @@ jobs:
       fail-fast: false
 
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6
 
       - name: Set up Python ${{ matrix.python-version }}
-        uses: actions/setup-python@v6
+        uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405  # v6
         with:
           python-version: ${{ matrix.python-version }}
 
@@ -38,9 +38,9 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6
 
-      - uses: actions/setup-python@v6
+      - uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405  # v6
         with:
           python-version: "3.12"
 
diff --git a/.github/workflows/codeql.yml b/.github/workflows/codeql.yml
index ddfa717..00a2652 100644
--- a/.github/workflows/codeql.yml
+++ b/.github/workflows/codeql.yml
@@ -17,7 +17,7 @@ jobs:
     name: analyze
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6
 
       - name: Detect languages
         id: detect
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index fc42a78..fc9acee 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -14,10 +14,10 @@ jobs:
     permissions:
       contents: read
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6
 
       - name: Set up Python
-        uses: actions/setup-python@v6
+        uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405  # v6
         with:
           python-version: "3.12"
 
@@ -36,10 +36,10 @@ jobs:
     permissions:
       contents: read
     steps:
-      - uses: actions/checkout@v6
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd  # v6
 
       - name: Set up Python
-        uses: actions/setup-python@v6
+        uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405  # v6
         with:
           python-version: "3.12"
 
@@ -71,7 +71,7 @@ jobs:
           python -m twine check dist/*
 
       - name: Upload distributions
-        uses: actions/upload-artifact@v7
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a  # v7
         with:
           name: python-dist
           path: dist/*
@@ -79,20 +79,27 @@ jobs:
   publish-pypi:
     needs: build
     runs-on: ubuntu-latest
+    # Trusted publishing (OIDC): no long-lived PYPI_API_TOKEN secret. PyPI
+    # verifies the GitHub OIDC identity for this repo/workflow/environment.
+    # Operator one-time step: add a PyPI trusted publisher for project
+    # "instinct-mcp" (owner WRG-11, repo instinct, workflow release.yml,
+    # environment pypi), then delete the PYPI_API_TOKEN repo secret.
+    environment:
+      name: pypi
+      url: https://pypi.org/project/instinct-mcp/
     permissions:
-      contents: read
+      id-token: write
     steps:
       - name: Download distributions
-        uses: actions/download-artifact@v8
+        uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c  # v8
         with:
           name: python-dist
           path: dist
 
       - name: Publish to PyPI
-        uses: pypa/gh-action-pypi-publish@release/v1
+        uses: pypa/gh-action-pypi-publish@cef221092ed1bacb1cc03d23a2d87d1d172e277b  # release/v1 @ 2026-02-18
         with:
           packages-dir: dist
-          password: ${{ secrets.PYPI_API_TOKEN }}
           skip-existing: true
 
   create-release:
@@ -103,7 +110,7 @@ jobs:
       contents: write
     steps:
       - name: Download distributions
-        uses: actions/download-artifact@v8
+        uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c  # v8
         with:
           name: python-dist
           path: dist