AetherLink

Architectural guardrails for AI agents. Written in Rust. MIT licensed.

AetherLink is an MCP server and a Claude Code PreToolUse hook that enforces a project's architectural rules at write-time. If an agent tries to grow a file past your line limit, introduce a forbidden import, or create a circular dependency, the write is blocked before it touches disk — and the agent gets the rejection reason on stderr so it can fix and retry.

The hook is the whole point: even if the agent has no idea AetherLink exists, every Edit / Write / MultiEdit call goes through it. The agent literally cannot route around it.

Install

macOS (Homebrew)

brew install DBrokenAI/tap/aetherlink
aetherlink --register        # add to Claude Desktop
aetherlink --install-hook    # add to Claude Code

Linux (curl | sh)

curl --proto '=https' --tlsv1.2 -LsSf \
  https://github.com/DBrokenAI/aetherlink/releases/latest/download/aetherlink-installer.sh | sh
aetherlink --register
aetherlink --install-hook

Windows (PowerShell)

irm https://github.com/DBrokenAI/aetherlink/releases/latest/download/aetherlink-installer.ps1 | iex
aetherlink --register
aetherlink --install-hook

(Or, on Windows, double-click install.bat from a release zip — same effect.)

From source (any OS)

git clone https://github.com/DBrokenAI/aetherlink
cd aetherlink
cargo build --release
./target/release/aetherlink --register
./target/release/aetherlink --install-hook

Supported rules

[rules]
# Reject any source file longer than this many lines.
max_file_lines = 500

# Block circular dependencies in the import graph.
no_cycles = true

# Block specific cross-folder imports. Format: "from -> to".
# Each side matches any directory component of a file's path,
# case-insensitively (so `ui -> db` catches `UI/Button.rs` on Linux too).
forbidden_imports = ["ui -> db", "api -> secret"]

Per-folder overrides and per-rule severity demotion are also supported — see src/rules/config.rs for the full schema.

Subcommands

aetherlink                Run as an MCP server on stdio (default)
aetherlink --register     Install into Claude Desktop's config
aetherlink --install-hook   Patch ~/.claude/settings.json (Claude Code)
aetherlink --uninstall-hook Remove the AetherLink hook entry
aetherlink --add          Interactively add a rule to AetherLink.toml
aetherlink --tray         Run the system tray health indicator
aetherlink --baseline [PATH]
                          Snapshot current violations into
                          .aetherlink-baseline.json
aetherlink --version
aetherlink --help

Bypass

Create an empty file named .aetherlink_bypass in the project root. AetherLink will allow writes through (with a CRITICAL warning) until you delete the file. Use this when something is wrong with the rules themselves, not as a way of life.

Cross-platform

CI builds and tests on Linux, macOS, and Windows on every push. The case-insensitive folder match in forbidden_imports is a deliberate design choice — without it, the same AetherLink.toml would enforce different rules on different developers' filesystems, which defeats the entire point.

License

MIT.