feat(ai): support GitHub Copilot CLI

AGENTS.md

@@ -0,0 +1 @@
+Project conventions, architecture, commands and hard-won gotchas live in CLAUDE.md. Read it before changing anything.

CHANGELOG.md

@@ -6,6 +6,11 @@ All notable changes to AngKorGit are documented here. The format follows
 
 ## [Unreleased]
 
+### Added
+- **GitHub Copilot CLI as an installed AI provider.** AngKorGit detects the
+  `copilot` binary, including WinGet installs on Windows, and runs prompts through
+  the user's existing Copilot login and quota with optional model overrides.
+
 ### Fixed
 - **"Show in file manager" on Windows opens the file's folder again.** Explorer was
   handed a path with forward slashes, quoted as a whole together with its `/select`

README.md

@@ -46,7 +46,7 @@ It's free, MIT licensed, and there is no account, no telemetry and no cloud. Eve
 
 **Remotes and accounts.** Fetch, pull and push through the same credential chain git uses. SSH keys and access tokens, several accounts on one host, identity profiles stored per repository and never in your global gitconfig. Pull requests from GitHub, GitLab and Bitbucket: list, check out, create, pick reviewers. Commit signing through your existing git config.
 
-**AI, if you want it.** A commit message from the staged diff, a plain explanation of a commit or a conflict, a review of what you are about to commit, a pull request description. It uses the AI CLI you already log into (Claude Code, Codex, Gemini CLI, OpenCode), or an API key, or Ollama on your own machine. Requests go straight from your computer to the provider you chose. Every one of them has a Stop button.
+**AI, if you want it.** A commit message from the staged diff, a plain explanation of a commit or a conflict, a review of what you are about to commit, a pull request description. It uses the AI CLI you already log into (Claude Code, GitHub Copilot CLI, Codex, Gemini CLI, OpenCode, Antigravity), or an API key, or Ollama on your own machine. Requests go straight from your computer to the provider you chose. Every one of them has a Stop button.
 
 **Keyboard first.** ⌘K opens a palette with every command in the app, shortcuts are printed next to menu items, Escape closes exactly one thing at a time.
 

SECURITY.md

@@ -28,9 +28,10 @@ For transparency, the app's security-relevant surface is:
   app's local settings (the webview's local storage on your machine), **not** in
   the OS keychain, and are sent only to the provider you configured. Prefer the
   installed-CLI or local-model providers if you'd rather store no key at all.
-- **AI CLIs** — if you select an installed AI CLI (Claude Code, Codex, Gemini
-  CLI, OpenCode), AngKorGit runs that binary as a local subprocess with your
-  user's permissions. Only a fixed allowlist of known CLI programs can be run.
+- **AI CLIs** — if you select an installed AI CLI (Claude Code, GitHub Copilot
+  CLI, Codex, Gemini CLI, OpenCode, Antigravity), AngKorGit runs that binary as a
+  local subprocess with your user's permissions. Only a fixed allowlist of known
+  CLI programs can be run.
 - **Network** — outbound only: git remotes you configure, Gravatar (avatar
   lookup by email hash), the AI provider you explicitly configure, and the
   updater, which checks GitHub Releases for a new signed build shortly after

apps/desktop/src-tauri/src/ai_cli.rs

@@ -9,6 +9,7 @@ use crate::error::{AppError, AppResult};
 
 const AGENTS: &[(&str, &str, &str)] = &[
     ("claude", "Claude Code", "claude"),
+    ("copilot", "GitHub Copilot CLI", "copilot"),
     ("codex", "Codex CLI", "codex"),
     ("gemini", "Gemini CLI", "gemini"),
     ("opencode", "OpenCode", "opencode"),
@@ -105,6 +106,12 @@ pub(crate) fn search_path(extra: Option<&Path>) -> std::ffi::OsString {
         if let Some(appdata) = std::env::var_os("APPDATA") {
             push(&mut dirs, PathBuf::from(appdata).join("npm"));
         }
+        if let Some(local_appdata) = std::env::var_os("LOCALAPPDATA") {
+            push(
+                &mut dirs,
+                PathBuf::from(local_appdata).join("Microsoft/WinGet/Links"),
+            );
+        }
     }
     std::env::join_paths(dirs).unwrap_or_default()
 }
@@ -366,6 +373,14 @@ mod tests {
         assert!(err.is_err());
     }
 
+    #[test]
+    fn accepts_github_copilot_cli_program() {
+        assert!(is_supported("copilot"));
+        assert!(is_supported("/usr/local/bin/copilot"));
+        #[cfg(windows)]
+        assert!(is_supported(r"C:\Program Files\GitHub Copilot\copilot.exe"));
+    }
+
     #[cfg(unix)]
     fn fake_agent(dir: &Path, body: &str) -> PathBuf {
         use std::os::unix::fs::PermissionsExt;

apps/desktop/src/features/settings/SettingsDialog.tsx

@@ -390,7 +390,7 @@ function CliAgentPicker() {
         <SettingEmpty
           icon={<SquareTerminal className="size-4" />}
           title="No AI CLI found"
-          description="Install Claude Code, Codex CLI, Gemini CLI, OpenCode or Antigravity CLI, then scan again."
+          description="Install Claude Code, GitHub Copilot CLI, Codex CLI, Gemini CLI, OpenCode or Antigravity CLI, then scan again."
           action={
             <Button variant="secondary" size="sm" onClick={() => void scan()}>
               <RefreshCw className="size-3.5" /> Scan again
@@ -1322,7 +1322,7 @@ export function SettingsDialog() {
                     title="Provider"
                     description={
                       settings.ai.provider === 'cli'
-                        ? 'Uses an AI CLI already installed on this machine — Claude Code, Codex, Gemini CLI, OpenCode or Antigravity — with its own login and quota. No API key needed.'
+                        ? 'Uses an AI CLI already installed on this machine — Claude Code, GitHub Copilot CLI, Codex, Gemini CLI, OpenCode or Antigravity — with its own login and quota. No API key needed.'
                         : 'Used for commit messages, diff explanations, conflict help and reviews. Local models via Ollama or LM Studio need no API key.'
                     }
                     action={

apps/website/src/components/AiSection.astro

@@ -3,6 +3,7 @@ import Commit from './Commit.astro';
 
 const providers = [
   { name: 'Claude Code', kind: 'CLI you already log into' },
+  { name: 'GitHub Copilot CLI', kind: 'CLI you already log into' },
   { name: 'Codex', kind: 'CLI you already log into' },
   { name: 'Gemini CLI', kind: 'CLI you already log into' },
   { name: 'OpenCode', kind: 'CLI you already log into' },
@@ -22,8 +23,9 @@ const providers = [
         <h2 class="display mt-3 text-4xl leading-[1.02] sm:text-5xl">Uses the AI you <em>already</em> have.</h2>
         <div class="mt-6 space-y-4 text-[17px] leading-relaxed text-muted">
           <p>
-            AngKorGit doesn't ship a model or a token wallet. If you've got Claude Code, Codex, Gemini CLI or OpenCode
-            installed, it finds the binary and uses your own login and quota. No key to paste.
+            AngKorGit doesn't ship a model or a token wallet. If you've got Claude Code, GitHub Copilot CLI, Codex,
+            Gemini CLI, OpenCode or Antigravity installed, it finds the binary and uses your own login and quota. No
+            key to paste.
           </p>
           <p>
             Or point it at an API key, or at Ollama on your own machine. Whatever you pick, requests go straight from
@@ -49,7 +51,7 @@ const providers = [
             <p class="text-[10px] uppercase tracking-[0.12em] text-faint">Detected on this machine</p>
             <ul class="mt-2 grid gap-1.5 sm:grid-cols-2">
               {
-                providers.slice(0, 4).map((p, i) => (
+                providers.slice(0, 5).map((p, i) => (
                   <li class:list={['flex items-center gap-2 rounded-md border px-2.5 py-2', i === 0 ? 'border-primary/50 bg-primary/10' : 'border-border-subtle bg-background']}>
                     <span class="flex h-6 w-6 items-center justify-center rounded-md bg-surface-raised font-mono text-[10px] text-muted">&gt;_</span>
                     <span class="flex min-w-0 flex-col leading-tight">

docs/Architecture.md

@@ -46,7 +46,7 @@ AngKorGit follows Clean Architecture with feature-based folders. Dependencies po
 
 **Conflict resolution as data.** Conflicted files are parsed into text/conflict blocks (`parseConflicts`), the resolver mutates block resolutions, and `serializeResolution` writes the result. Unresolved blocks re-emit their markers, so a half-finished session never destroys data.
 
-**AI is an adapter registry.** Features call capabilities (`generateCommitMessage`, `explainConflict`, …) against the `AiProvider` interface. API providers (OpenAI, Anthropic, Gemini, Ollama, LM Studio) are created from config; HTTP goes through an injected transport implemented by a Rust proxy (no CORS, keys stay out of webview fetch). The `cli` provider is different: it runs an AI CLI already installed on the machine (Claude Code, Codex, Gemini CLI, OpenCode) as an allowlisted local subprocess via `ai_cli.rs` — the user's own login and quota, no API key. Adding an API provider touches one file; adding a CLI agent touches `cliAgents.ts` plus the `ai_cli.rs` allowlist.
+**AI is an adapter registry.** Features call capabilities (`generateCommitMessage`, `explainConflict`, …) against the `AiProvider` interface. API providers (OpenAI, Anthropic, Gemini, Ollama, LM Studio) are created from config; HTTP goes through an injected transport implemented by a Rust proxy (no CORS, keys stay out of webview fetch). The `cli` provider is different: it runs an AI CLI already installed on the machine (Claude Code, GitHub Copilot CLI, Codex, Gemini CLI, OpenCode, Antigravity) as an allowlisted local subprocess via `ai_cli.rs` — the user's own login and quota, no API key. Adding an API provider touches one file; adding a CLI agent touches `cliAgents.ts` plus the `ai_cli.rs` allowlist.
 
 **Credentials are layered, host-scoped, and never global.** App-managed accounts (tokens in the OS keyring under AngKorGit's own service, matched to remotes by host) come first, then SSH agent/keys, then the system `git credential` stack — so a GitLab token is never offered to GitHub. The same philosophy applies to committer identity: profiles apply to a repository's local config only, never the shared global gitconfig other tools fight over.
 

docs/Development.md

@@ -47,9 +47,10 @@ The engine lives in `apps/desktop/src-tauri/src/core/`, one module per domain ar
 2. Register it in `createAiProvider` and `AI_PROVIDER_PRESETS`.
 3. Done — settings UI, capabilities and transport pick it up automatically.
 
-Installed AI-CLI agents (Claude Code, Codex, Gemini CLI, OpenCode) follow a different
-path: add the agent's argv/stdin shape in `packages/core/src/ai/cliAgents.ts` and its
-binary to the allowlist in `apps/desktop/src-tauri/src/ai_cli.rs`.
+Installed AI-CLI agents (Claude Code, GitHub Copilot CLI, Codex, Gemini CLI,
+OpenCode, Antigravity) follow a different path: add the agent's argv/stdin shape
+in `packages/core/src/ai/cliAgents.ts` and its binary to the allowlist in
+`apps/desktop/src-tauri/src/ai_cli.rs`.
 
 ## Release
 

docs/Roadmap.md

@@ -18,7 +18,7 @@ direction.
 - [x] Diff: inline & side-by-side, syntax highlight, word diff, image diff, find in diff (⌘F), minimap, previous/next change and file navigation (N/P, [/]), opens directly at the first change (no scroll animation), reloads live as the file changes on disk, file history one click from the header; → / ↑ ↓ / ← walk from the graph into a commit's files and back
 - [x] Settings: sixteen themes (Angkor Dusk default) with accents & zoom, identity profiles (repo-local) with linked accounts, SSH key management & generation, hosting accounts with verified tokens (Secret Service on Linux, missing tokens flagged), AI providers & commit style, keyboard reference
 - [x] Sidebar: accordion sections with pinned headers and collapse-all, row menus on hover and right-click everywhere, empty-state cards; graph display options and column headers; welcome page with keyboard navigation and missing-folder detection
-- [x] AI: provider-agnostic (OpenAI, Anthropic, Gemini, Ollama, LM Studio) plus installed AI CLIs (Claude Code, Codex, Gemini CLI, OpenCode, Antigravity) — commit messages, diff/conflict explanations, PR descriptions, staged-change review with team conventions (global + per-repo `.angkorgit/review.md`), background execution with stop, full-size reading views
+- [x] AI: provider-agnostic (OpenAI, Anthropic, Gemini, Ollama, LM Studio) plus installed AI CLIs (Claude Code, GitHub Copilot CLI, Codex, Gemini CLI, OpenCode, Antigravity) — commit messages, diff/conflict explanations, PR descriptions, staged-change review with team conventions (global + per-repo `.angkorgit/review.md`), background execution with stop, full-size reading views
 - [x] Undo/redo for recent operations; drag-and-drop merge/rebase
 - [x] Auto-update: pull-based from GitHub releases, signature-verified
 - [x] Commit signing: SSH and GPG, driven by existing git config (commit.gpgSign, gpg.format, user.signingKey) — covers commit, amend, merge

packages/core/src/ai/cliAgents.ts

@@ -27,6 +27,23 @@ export const CLI_AGENTS: Record<CliAgentId, CliAgentSpec> = {
     promptVia: 'stdin',
     args: (model) => ['-p', '--output-format', 'text', ...(model ? ['--model', model] : [])],
   },
+  copilot: {
+    id: 'copilot',
+    label: 'GitHub Copilot CLI',
+    binary: 'copilot',
+    promptVia: 'arg',
+    args: (model) => [
+      '--silent',
+      '--stream',
+      'off',
+      '--no-ask-user',
+      '--no-color',
+      '--output-format',
+      'text',
+      ...(model ? ['--model', model] : []),
+      '--prompt',
+    ],
+  },
   codex: {
     id: 'codex',
     label: 'Codex CLI',

packages/core/src/ai/providers.ts

@@ -225,7 +225,7 @@ export const AI_PROVIDER_PRESETS: Record<
   AiProviderKind,
   { label: string; defaultModel: string; needsApiKey: boolean; defaultBaseUrl: string }
 > = {
-  cli: { label: 'Installed AI CLI (Claude Code, Codex…)', defaultModel: '', needsApiKey: false, defaultBaseUrl: '' },
+  cli: { label: 'Installed AI CLI (Claude, Copilot, Codex…)', defaultModel: '', needsApiKey: false, defaultBaseUrl: '' },
   openai: { label: 'OpenAI', defaultModel: 'gpt-4o-mini', needsApiKey: true, defaultBaseUrl: 'https://api.openai.com/v1' },
   anthropic: { label: 'Anthropic', defaultModel: 'claude-sonnet-5', needsApiKey: true, defaultBaseUrl: 'https://api.anthropic.com' },
   gemini: { label: 'Google Gemini', defaultModel: 'gemini-2.0-flash', needsApiKey: true, defaultBaseUrl: 'https://generativelanguage.googleapis.com' },

packages/core/src/ai/types.ts

@@ -45,7 +45,7 @@ export type AiProviderKind =
   | 'ollama'
   | 'lmstudio';
 
-export type CliAgentId = 'claude' | 'codex' | 'gemini' | 'opencode' | 'antigravity';
+export type CliAgentId = 'claude' | 'copilot' | 'codex' | 'gemini' | 'opencode' | 'antigravity';
 
 export interface CliAgentInfo {
   id: CliAgentId;

tests/unit/cliAgents.test.ts

@@ -97,6 +97,21 @@ describe('cli agent specs', () => {
     expect(CLI_AGENTS.opencode.promptVia).toBe('arg');
   });
 
+  it('copilot runs one silent, non-interactive prompt without asking the user', () => {
+    expect(CLI_AGENTS.copilot.promptVia).toBe('arg');
+    expect(CLI_AGENTS.copilot.args('')).toEqual([
+      '--silent',
+      '--stream',
+      'off',
+      '--no-ask-user',
+      '--no-color',
+      '--output-format',
+      'text',
+      '--prompt',
+    ]);
+    expect(CLI_AGENTS.copilot.args('gpt-5.4')).toContain('gpt-5.4');
+  });
+
   it('antigravity puts -p last so the appended prompt becomes its value', () => {
     expect(CLI_AGENTS.antigravity.promptVia).toBe('arg');
     expect(CLI_AGENTS.antigravity.args('').at(-1)).toBe('-p');