Add agent skills support /google-styleguide

.github/workflows/check-agent-skills.yml

@@ -0,0 +1,93 @@
+# Copyright 2026 Google LLC
+#
+# 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
+#
+#     https://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: Check Agent Skills
+
+on:
+  push:
+    branches: [ main, master, gh-pages ]
+  pull_request:
+    branches: [ main, master, gh-pages ]
+
+jobs:
+  check-skills:
+    # Run the checks on the latest Ubuntu environment
+    runs-on: ubuntu-latest
+    steps:
+      # Step 1: Checkout the repository code to access the files locally
+      - name: Checkout Code
+        uses: actions/checkout@v4
+
+      # Step 2: Extract the list of style guide reference keys from the README.md references block
+      - name: Extract Style Guide Keys from README.md
+        run: |
+          # Extract all style guide reference keys defined between the START/END markers,
+          # remove the brackets and colon, and sort the list alphabetically.
+          echo "Extracting style guide keys from README.md..."
+          README_KEYS=$(sed -n '/<!-- START_STYLEGUIDES -->/,/<!-- END_STYLEGUIDES -->/p' README.md \
+            | grep -E '^\[[a-zA-Z0-9_-]+\]:' \
+            | grep -o -E '^\[[a-zA-Z0-9_-]+\]' \
+            | tr -d '[]' \
+            | sort)
+
+          # Write the list to a temporary file for differential comparison in a later step
+          echo "$README_KEYS" > readme_keys.tmp
+
+      # Step 3: Extract the list of style guide languages from SKILL.md and normalize them to keys
+      - name: Extract Style Guide Keys from SKILL.md
+        run: |
+          # Extract the Language column values from the Supported Style Guides table in SKILL.md,
+          # convert to lowercase, remove markdown formatting, and map them to their corresponding
+          # README reference keys (using a normalized sed translation map).
+          echo "Extracting style guide keys from SKILL.md..."
+          SKILL_KEYS=$(grep '|' skills/google-styleguide/SKILL.md \
+            | tail -n +3 \
+            | cut -d'|' -f2 \
+            | tr -d '* ' \
+            | tr '[:upper:]' '[:lower:]' \
+            | sed -E -e 's/angularjs/angular/' \
+                     -e 's/commonlisp/cl/' \
+                     -e 's/c\+\+/cpp/' \
+                     -e 's/c#/csharp/' \
+                     -e 's/html\/css/htmlcss/' \
+                     -e 's/javascript/js/' \
+                     -e 's/objective-c/objc/' \
+                     -e 's/python/py/' \
+                     -e 's/shell/sh/' \
+                     -e 's/typescript/ts/' \
+                     -e 's/vimscript/vim/' \
+            | sort)
+
+          # Write the list to a temporary file for differential comparison in a later step
+          echo "$SKILL_KEYS" > skill_keys.tmp
+
+      # Step 4: Compare the two sets of keys and fail if they have diverged
+      - name: Verify README.md and SKILL.md style guides are in sync
+        run: |
+          # Perform a differential comparison between the two sets of extracted reference keys
+          DIFF_OUT=$(diff readme_keys.tmp skill_keys.tmp || true)
+
+          # Clean up temporary files
+          rm -f readme_keys.tmp skill_keys.tmp
+
+          # Fail the build if any divergence is found
+          if [[ -n "$DIFF_OUT" ]]; then
+            echo "Error: README.md style guides and skills/google-styleguide/SKILL.md support different languages!" >&2
+            echo "Differences (- README.md, + SKILL.md):" >&2
+            echo "$DIFF_OUT" >&2
+            exit 1
+          else
+            echo "Success: README.md and skills/google-styleguide/SKILL.md supported languages are in sync!"
+            exit 0
+          fi

README.md

@@ -75,11 +75,11 @@ primarily optimizing for Google's internal needs.
 
 <a rel="license" href="https://creativecommons.org/licenses/by/3.0/"><img alt="Creative Commons License" style="border-width:0" src="https://i.creativecommons.org/l/by/3.0/88x31.png" /></a>
 
+<!-- START_STYLEGUIDES -->
 [cpp]: https://google.github.io/styleguide/cppguide.html
 [csharp]: https://google.github.io/styleguide/csharp-style.html
 [swift]: https://google.github.io/swift/
 [objc]: objcguide.md
-[gh-tracker]: https://github.com/google/styleguide/issues
 [go]: go/
 [java]: https://google.github.io/styleguide/javaguide.html
 [json]: https://google.github.io/styleguide/jsoncstyleguide.xml
@@ -94,9 +94,13 @@ primarily optimizing for Google's internal needs.
 [angular]: https://google.github.io/styleguide/angularjs-google-style.html
 [cl]: https://google.github.io/styleguide/lispguide.xml
 [vim]: https://google.github.io/styleguide/vimscriptguide.xml
-[emacs]: https://raw.githubusercontent.com/google/styleguide/gh-pages/google-c-style.el
 [xml]: https://google.github.io/styleguide/xmlstyle.html
 [dart]: https://www.dartlang.org/guides/language/effective-dart
+<!-- END_STYLEGUIDES -->
+
+[gh-tracker]: https://github.com/google/styleguide/issues
+[emacs]: https://raw.githubusercontent.com/google/styleguide/gh-pages/google-c-style.el
 [ccl]: https://creativecommons.org/licenses/by/3.0/
 [SCM]: https://en.wikipedia.org/wiki/Source_control_management
 [VCS]: https://en.wikipedia.org/wiki/Version_control_system
+

skills/google-styleguide/SKILL.md

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+---
+name: google-styleguide
+description: Validates and refactors code in the target codebase to adhere to the official Google Style Guides across multiple supported languages.
+---
+
+## Core Concept
+
+The `google-styleguide` skill ensures that a codebase conforms to Google's official style conventions. Because modern codebases often mix multiple languages, this skill helps identify language-specific files and checks each one against its corresponding style guide.
+
+## Supported Style Guides
+
+| Language | File Extensions | Style Guide URL |
+| :--- | :--- | :--- |
+| **AngularJS** | `.js`, `.html` | [AngularJS Style Guide](guides/angularjs-google-style.html) |
+| **Common Lisp** | `.lisp`, `.lsp`, `.cl` | [Common Lisp Style Guide](guides/lispguide.xml) |
+| **C++** | `.cpp`, `.cc`, `.cxx`, `.hpp`, `.h`, `.hh` | [C++ Style Guide](guides/cppguide.html) |
+| **C#** | `.cs` | [C# Style Guide](guides/csharp-style.md) |
+| **Dart** | `.dart` | [Effective Dart](https://www.dartlang.org/guides/language/effective-dart) |
+| **Go** | `.go` | [Go Style Guide](guides/go/index.md) |
+| **HTML/CSS** | `.html`, `.css` | [HTML/CSS Style Guide](guides/htmlcssguide.html) |
+| **JavaScript** | `.js`, `.mjs`, `.cjs` | [JavaScript Style Guide](guides/jsguide.html) |
+| **Java** | `.java` | [Java Style Guide](guides/javaguide.html) |
+| **JSON** | `.json`, `.jsonc` | [JSON Style Guide](guides/jsoncstyleguide.xml) |
+| **Kotlin** | `.kt`, `.kts` | [Kotlin Style Guide](https://developer.android.com/kotlin/style-guide) |
+| **Markdown** | `.md` | [Markdown Style Guide](guides/docguide/style.md) |
+| **Objective-C** | `.m`, `.mm`, `.h` | [Objective-C Style Guide](guides/objcguide.md) |
+| **Python** | `.py`, `.pyi` | [Python Style Guide](guides/pyguide.md) |
+| **R** | `.r`, `.R` | [R Style Guide](guides/Rguide.md) |
+| **Shell** | `.sh`, `.bash`, `.zsh` | [Shell Style Guide](guides/shellguide.md) |
+| **Swift** | `.swift` | [Swift Style Guide](https://google.github.io/swift/) |
+| **TypeScript** | `.ts`, `.tsx` | [TypeScript Style Guide](guides/tsguide.html) |
+| **Vim script** | `.vim`, `.vimrc` | [Vim script Style Guide](guides/vimscriptguide.xml) |
+| **XML** | `.xml` | [XML Document Format Style Guide](guides/xmlstyle.html) |
+
+## Workflow Patterns
+
+When invoked to check or refactor a codebase for style guide compliance:
+
+### 1. Identify File Languages
+Scan the current workspace to locate files matching the supported file extensions. Group files by language (e.g., Python files under `.py`, JavaScript files under `.js`).
+
+### 2. Locate and Read the Style Guide
+Determine which style guides are needed based on the file types present in the project. For each language under review, refer to the Supported Style Guides table above:
+- **Local Guides (Symlinked)**: If the guide points to a local file or folder path (e.g. `guides/cppguide.html`, `guides/pyguide.md`, `guides/go/index.md`, etc.), you **MUST** read the contents of that local file directly from this skill's directory using your file-viewing tools to get the style guidelines.
+- **External Guides**: If the guide points to a remote URL (Dart, Kotlin, Swift), access the remote documentation using web browsing/reading tools.
+
+### 3. Core Compliance Auditing
+For each file being checked:
+1. **Naming Conventions**: Check variable names, class names, method/function names, constants, and file names (e.g., `camelCase` vs `snake_case` or `PascalCase`).
+2. **Formatting**: Ensure indentation (e.g., 2 spaces vs 4 spaces vs tabs), maximum line length, and brace placement conform.
+3. **Language Features**: Ensure restricted language features are not used (e.g., no global variables, no raw exceptions in C++ unless specified, etc.).
+4. **Imports/Includes**: Review import structures, sorting order, and use of absolute vs relative paths.
+5. **Comments & Docs**: Ensure docstrings and file comments adhere to formatting, positioning, and language requirements.
+
+### 4. Non-Destructive Refactoring
+Make changes to files to match style guide specifications. Use precise code-editing tools to preserve all logic and behavior of the code. Run any existing test suites to verify functionality is not altered by styling changes.

skills/google-styleguide/guides/Rguide.md

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+../../../Rguide.md

skills/google-styleguide/guides/angularjs-google-style.html

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+../../../angularjs-google-style.html

skills/google-styleguide/guides/cppguide.html

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+../../../cppguide.html

skills/google-styleguide/guides/csharp-style.md

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+../../../csharp-style.md

skills/google-styleguide/guides/docguide/README.md

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+../../../../docguide/README.md

skills/google-styleguide/guides/docguide/READMEs.md

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+../../../../docguide/READMEs.md

skills/google-styleguide/guides/docguide/VERSION

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+../../../../docguide/VERSION

skills/google-styleguide/guides/docguide/best_practices.md

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+../../../../docguide/best_practices.md

skills/google-styleguide/guides/docguide/philosophy.md

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+../../../../docguide/philosophy.md

skills/google-styleguide/guides/docguide/style.md

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+../../../../docguide/style.md

skills/google-styleguide/guides/go/best-practices.md

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+../../../../go/best-practices.md

skills/google-styleguide/guides/go/decisions.md

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+../../../../go/decisions.md

skills/google-styleguide/guides/go/guide.md

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+../../../../go/guide.md

skills/google-styleguide/guides/go/index.md

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+../../../../go/index.md

skills/google-styleguide/guides/htmlcssguide.html

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+../../../htmlcssguide.html

skills/google-styleguide/guides/javaguide.html

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+../../../javaguide.html

skills/google-styleguide/guides/jsguide.html

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+../../../jsguide.html

skills/google-styleguide/guides/jsoncstyleguide.xml

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+../../../jsoncstyleguide.xml

skills/google-styleguide/guides/lispguide.xml

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+../../../lispguide.xml

skills/google-styleguide/guides/objcguide.md

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+../../../objcguide.md

skills/google-styleguide/guides/pyguide.md

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+../../../pyguide.md

skills/google-styleguide/guides/shellguide.md

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+../../../shellguide.md

skills/google-styleguide/guides/tsguide.html

@@ -0,0 +1 @@
+../../../tsguide.html

skills/google-styleguide/guides/vimscriptguide.xml

@@ -0,0 +1 @@
+../../../vimscriptguide.xml

skills/google-styleguide/guides/xmlstyle.html

@@ -0,0 +1 @@
+../../../xmlstyle.html

skills/google-styleguide/resources/eclipse-cpp-google-style.xml

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+../../../eclipse-cpp-google-style.xml

skills/google-styleguide/resources/eclipse-java-google-style.xml

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+../../../eclipse-java-google-style.xml

skills/google-styleguide/resources/google-c-style.el

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+../../../google-c-style.el

skills/google-styleguide/resources/google_python_style.vim

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+../../../google_python_style.vim

skills/google-styleguide/resources/intellij-java-google-style.xml

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+../../../intellij-java-google-style.xml

skills/google-styleguide/resources/javaguide.css

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+../../../javaguide.css

skills/google-styleguide/resources/pylintrc

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+../../../pylintrc

skills/google-styleguide/resources/styleguide.css

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+../../../styleguide.css

skills/google-styleguide/resources/styleguide.xsl

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+../../../styleguide.xsl