aevrin

aevrin

This package has moved to npm. 0.9.3 is the last Python release of the aevrin CLI. It prints a notice on every run, and it never pulls the scan engine image, so its local scans end incomplete unless you built that image yourself. Install the new CLI with npm install -g aevrin (Node.js 22 or later), which builds the image for you, then remove this one with pip uninstall aevrin aevrin-scanner.

Aevrin MCP Security Scanner CLI. Wraps the same open-source scanner binaries and normalization logic (aevrin-scanner) that the Aevrin backend uses, run locally against your own machine. Results save to your Aevrin dashboard automatically once you're logged in, pass --no-upload for a purely local, ephemeral scan.

Install

python3 -m pip install --upgrade aevrin

The same CLI is also available through npm:

npm install --global aevrin

Requires Docker using Linux containers: a scan starts the MCP server inside one disposable, version-pinned engine image, which is pulled automatically when missing. On Docker Desktop, assign at least 4 GB of memory and permit bind mounts from the system temporary directory. There is no non-Docker fallback - an unavailable sandbox is an unavailable scan, never a scan performed without one - so use --remote for a local folder if you would rather not run Docker.

Usage

aevrin scan mcp "npx -y @playwright/mcp"   # scan a server by its launch command
aevrin scan ./my-mcp-server
aevrin scan github.com/owner/repo
aevrin scan https://my-live-server.example.com --json
aevrin scan ./my-mcp-server --fail-on high
aevrin scan ./my-mcp-server --no-upload   # skip saving to your dashboard (e.g. in CI)

Target type is auto-detected: a github.com URL, another public https:// URL as a live MCP server, or anything that exists on disk as a local path. The same checks run either way - one engine over the tools a live server actually returns, in five stages (resolving, launching, enumerating, analyzing, grading) - and the target type only changes how resolving works out what to start. Private, loopback, metadata, credential-bearing, and plain-HTTP live targets are rejected. Aevrin never executes submitted stdio MCP commands.

Flags

Exit codes

Results go to stdout; stage progress and diagnostics go to stderr, safe to pipe --json output without stage-progress noise mixed in.

Aevrin prints one grade letter and a risk score, then each finding as its own block rather than a table row, because a table forced every finding down to a title. Stage progress is listed above it. Run aevrin scan --help, or see the full reference for the exact shape: https://docs.mcp.aevrin.net/cli.

Other commands

aevrin login / logout           # browser device-code login, credentials in ~/.aevrin
aevrin agent scan               # what the AI coding agents on this machine may do
aevrin agent scan --json        # versioned snapshot; never contains a credential value
aevrin findings triage <id> <status> [--reason ...]
aevrin mcp-server               # local stdio MCP server with one tool, scan_mcp_server
aevrin mcp-header               # print the Authorization header for Aevrin MCP
aevrin registry publish <dir>   # Aevrin administrators only

mcp-server needs the MCP extra: pip install "aevrin[mcp]", and registry publish the YAML extra: pip install "aevrin[registry]".

Aevrin MCP (https://api.mcp.aevrin.net/mcp) needs your Aevrin API key. mcp-header prints {"Authorization":"Bearer <key>"} from the key aevrin login stored, so Claude Code can read it without the key being written into its config:

claude mcp add-json --scope user aevrin '{"type":"http","url":"https://api.mcp.aevrin.net/mcp","headersHelper":"aevrin mcp-header"}'

agent scan reads configuration only: no agent is started and nothing from a config file is executed. Nothing leaves the machine without --upload. Full reference: https://mcp.aevrin.net/docs/cli.

Development

uv sync
uv run pytest tests -v
uv run ruff check .
uv run mypy -p aevrin.cli