Instructions file GitHub Copilot
Instructions for chromium/chromium, covering github copilot instructions, project knowledge: chromium, project overview, git workflow (strict) and c++ includes.
Skill Claude CodeCodex
Resolves git merge conflicts. Files should show in "git status" and contain conflict markers ("<<<<").
Skill Claude CodeCodex
Expert in Chromium code editing following project style guides and best practices.
Agent
This policy is for Chromium developers using AI tools to help write code. It is intended to outline expectations around the use of such tools.
Skill Claude CodeCodex
Modularize a chrome/browser/ subfolder by splitting its sources out of the monolithic //chrome/browser:browser target into dedicated sourceset targets in the subfolder's own BUILD.gn. Use when the user asks to modularize, extract, or create BUILD targets for a chrome/browser/ subfolder, or mentions "Project Bedrock"…
Skill Claude CodeCodex
Researcher for converting unit tests to browser tests for Project Bedrock. Invoke this when the user needs to understand the current codebase behavior while removing complex Browser dependencies from tests.
Skill Claude CodeCodex
Reviewer for converting unit tests to browser tests for Project Bedrock. Invoke this when the user needs to review their work while removing complex Browser dependencies from tests.
Skill Claude CodeCodex
Workflow for converting unit tests to browser tests for Project Bedrock. Invoke this when the user wants to remove complex Browser dependencies from tests.
Skill Claude CodeCodex
Critique and review Figma designs to ensure alignment with Chromium codebase components, tokens, and structure. Use when the user asks to critique, review, or audit a design, check alignment with code, or compare a Figma node against component specifications or coding standards.
Skill Claude CodeCodex
Recreate Figma design frames as prototype-ready Chromium Views JSON script following Chrome's native Views architecture, component guidelines, and color/shape token mappings. Use when asked to create C++ Views Prototype JSON script from a Figma frame URL.
Skill Claude CodeCodex
Recreate Figma design frames as production-ready Chromium C++ Views code following Chrome's native Views architecture, component guidelines, and color/shape token mappings. Use when asked to create C++ Views code from a Figma frame URL.
Skill Claude CodeCodex
Recreate Figma design frames as production-ready Chromium WebUI code following Chrome's Lit-element architecture and styling guidelines. Use when asked to create WebUI code from a Figma frame URL.
Skill Claude CodeCodex
Maps a Figma component from the Chrome Design System (CDS) to equivalent C++ Views, WebUI, and Clank (Android) components in the Chromium codebase. Generates a comprehensive side-by-side comparative Markdown specification detailing layout variants, interactive states, design tokens, architectural and implementation…
Skill Claude CodeCodex
Maps all Figma design tokens from figma-variables.md to their equivalent C++ (Views) identifiers, CSS (WebUI) variables, and Clank (Android) resource attributes/macros/methods in Chromium, and saves the formatted mapping table to the assets directory of the Chrome Design System project. Use this skill when asked to…
Skill Claude CodeCodex
Use this skill whenever you need to look up or reference Chrome Design System component specs or design token mappings.
Skill Claude CodeCodex
Finds common violations of the Android accessibility API in the Clank App Java code and attempts to address them (e.g. hardcoded state change announcements, missing events, focus moving, assertive live regions, etc).
Skill Claude CodeCodex
Identify and safely remove expired Chromium histograms (dead metrics/technical debt). Use this skill when a contributor asks to clean up metrics, fix code health issues related to histograms, remove obsolete code, or work on a histogram cleanup task.
Skill Claude CodeCodex
Extension pipeline to bump expiration dates of Chromium UMA histograms.
Skill Claude CodeCodex
Orchestrator for the "Code Health Hub" framework. Trigger only when the user refers to the Hub or asks to see "available cleanup tasks" within the Chromium technical debt reduction system.
Skill Claude CodeCodex
Identify and clean up inline fully qualified Java names (FQNs) in first-party code, replacing them with standard imports.
Skill Claude CodeCodex
Automatically detects misordered lists in code (like Android XMLs), injects go/keep-sorted tags, sorts them, and creates CLs.
Skill Claude CodeCodex
Add missing LINT.IfChange(...) / LINT.ThenChange(...) guards to enums in C++/Java and XML to keep them in sync. Trigger this skill ONLY when a contributor explicitly asks to add lint guards or synchronize enums using LINT guards.
Skill Claude CodeCodex
Replace anonymous classes with lambdas where applicable (SAM interfaces).
Skill Claude CodeCodex
Find and fix unsafe buffer operations in a C++ file by removing UNSAFETODO markers and replacing unsafe raw pointers/C-style functions with base::span and standard safe containers. Use when the user asks to fix unsafe buffer warnings or -Wunsafe-buffer-usage errors. Don't use for other types of memory safety bugs like…