Repo Name Checker

Check the availability of a repo name against the major package registries (NPM, PyPI, crates.io).

Usage

uvx repo-name-checker foobarbaz

Produces a table:

Pass a list of registries to narrow the check:

uvx repo-name-checker foobarbaz --registry npm --registry pypi

Publish-time collision detection (npm)

npm rejects publishes whose normalized form (lowercased, with -/_/. removed) matches an existing package. The Collisions column lists existing names that would block your publish — for example darkfactory collides with dark-factory. The check is best-effort: npm's exact internal algorithm is private, so a passing check is necessary but not sufficient.

Output format

Use --format to choose the output. table is the default; json emits a machine-readable list:

$ uvx repo-name-checker foobarbaz --format json
[
  {"registry": "npm", "name": "foobarbaz", "available": false, "collisions": ["foo-bar-baz"]},
  {"registry": "pypi", "name": "foobarbaz", "available": true, "collisions": []},
  {"registry": "crates", "name": "foobarbaz", "available": true, "collisions": []}
]

The CLI exits 0 if at least one registry has the name available, otherwise 1.

SDK

The CLI is a thin wrapper over a Python SDK with 1:1 parity:

import asyncio
from repo_name_checker import check, check_sync

# Async
results = asyncio.run(check("foobarbaz", registries=["npm", "pypi"]))

# Sync
results = check_sync("foobarbaz")

for r in results:
    print(r.registry, r.available)

License

MIT