Funveil

A lightweight tool for controlling file visibility in AI agent workspaces.

Overview

Funveil creates a "veiled" view of a codebase where specific files or line ranges can be hidden from an AI agent while preserving file structure and line numbers.

Key Features

• Two modes: Whitelist (show only what's needed) or Blacklist (hide secrets)
• Physical file removal: Fully-veiled files are removed from disk, not replaced with markers
• Partial veils: Hide specific line ranges within files
• Content-addressable storage: Hidden content stored with SHA-256 hash
• Metadata system: Parsed symbol metadata stored alongside CAS for blind queries (details)
• Query-based unveiling: Unveil by symbol name, callers, or callees (--symbol, --callers-of, --callees-of)
• Layered disclosure: 4 levels from metadata-only to full source (--level 0-3)
• Token budget mode: Automatic disclosure planning within a token budget (fv disclose --budget)
• Smart context: Unveil a function and its dependencies (fv context <fn> --depth N)
• Permission preservation: Original Unix permissions restored on unveil
• Undo/redo: Reversible veil operations with full action history
• Checkpoints: Save and restore veil states
• Profiles: Save/load named veil configurations (fv profile save/load)
• Glob patterns: Shell-style wildcards for matching files (*.py, src/**/*.rs)
• Progressive defaults: Outline mode for fv show, code-only fv entrypoints, depth-1 fv trace
• 12-language parsing: Code-aware veiling with tree-sitter (details)

Quick Start

# Initialize (default: whitelist mode)
fv init

# Unveil what the agent needs
fv unveil README.md
fv unveil src/public_api.py

# Check status
fv status

# Before committing, unveil everything
fv unveil --all
git add .
git commit -m "Changes"

# Restore veils for next session
fv restore

Building

cargo build --release

Documentation

• docs/TUTORIAL.md - Start here
• SPEC.md - Specification index
• specs/ - Detailed specs (config, storage, veil format, CLI, algorithms)
• docs/LANGUAGE_FEATURES.md - Supported languages & analysis
• CONTRIBUTING.md - Development setup
• MUTATION_TESTING.md - Mutation testing guide & results
• Running under gVisor — OS-level sandboxing with runsc

License

AGPL-3.0