Brela — AI Attribution (VS Code Extension)

Silently tracks which AI tools wrote which lines in your codebase — without changing your workflow.

Brela watches your editor in the background and records every AI-generated insertion: GitHub Copilot completions, Claude Code agent writes, Cursor suggestions, Windsurf, Cline, and more. Run brela report or brela explain <file> to see a breakdown anytime.

Features

Zero friction — no UI, no popups, no workflow changes
Accurate attribution — distinguishes inline completions from agent writes; correctly separates Copilot Chat from Claude Code; CLI agent runs from extension completions
All major tools — Copilot, Copilot CLI, Claude Code, Cursor, Windsurf, Cline, Continue, Aider
Local only — all session data stays in .brela/ inside your project, never sent anywhere

How it works

The extension runs three listeners silently:

onDidChangeTextDocument — detects large multi-line insertions (≥3 newlines, ≥120 chars) and attributes them to the active AI extension
onDidSaveTextDocument — catches agent saves (files written directly to disk by a CLI agent)
File creation watcher — records new files created by agents

Shell intent from brela shell wrappers (claude, gh copilot) takes highest priority — so CLAUDE_CODE_AGENT is always correctly separated from Copilot Chat.

Detection logic

Scenario	Attributed as
Large insertion, only Copilot active	`COPILOT`
Large insertion, only Claude Code active	`CLAUDE_CODE`
Both Copilot + Claude Code active	`COPILOT` (conservative — inline is ambiguous)
File saved after `claude` shell run	`CLAUDE_CODE_AGENT`
File saved after `gh copilot` shell run	`COPILOT_CLI`
Cursor extension or `.cursorrules`	`CURSOR`
Windsurf extension or `.windsurfrules`	`CODEIUM`
2+ files changed within 2 seconds	`MULTI_FILE_BURST`
Git commit has `Co-Authored-By: Claude`	`CLAUDE_CODE`

Setup

The extension is installed automatically by brela init. To install manually:

npm install -g @brela-dev/cli
brela init

Session files

Attributions are written to .brela/sessions/YYYY-MM-DD.json in your workspace (NDJSON). Use brela report or brela explain <file> from the @brela-dev/cli package to read them.

Part of Brela

See the root repo for the CLI, core types, and full documentation.