Supercov — Security skill for Claude Code


**Coverage, security and code quality for coding agents**

**Supercov tells your coding agent what to fix and what to test.** It scores your code quality and flags security risks with [Jev](https://typesafe.ai), runs the test command you already use, and turns uncovered paths into small, actionable queries. Your agent picks a target, writes a focused test or a focused refactor, proves what improved, and keeps going.

Paste this to your coding agent to start:

Measure code quality with npx supercov.

Scoring needs a [TypeSafe AI](https://typesafe.ai) API key, and your coding agent will usually ask you for it. It costs about a cent per megabyte of source. Coverage needs no account, config file, import, custom reporter, or hosted service. Supercov is local, free, open source, and MIT licensed.

[Website](https://supercov.com) · [Documentation](https://supercov.com/docs) · [npm](https://www.npmjs.com/package/supercov) · [GitHub](https://github.com/supercorp-ai/supercov)

Supported languages: [JavaScript](https://supercov.com/docs/javascript) · [TypeScript](https://supercov.com/docs/javascript) · [Rust](https://supercov.com/docs/rust) · [Python](https://supercov.com/docs/python) · [Ruby](https://supercov.com/docs/ruby) · [Go](https://supercov.com/docs/go) · [Java](https://supercov.com/docs/java) · [Kotlin](https://supercov.com/docs/kotlin).

In Claude Code, Codex and Gemini CLI you can also [install it as a plugin](#give-supercov-a-job).

Supported by [Supercorp](https://supercorp.ai).

[Agent workflow](https://supercov.com/docs/agent-loop): ask your coding agent to add a test in your own project, with a recorded example to follow along.

Score your code

export TYPESAFE_API_KEY=...   # get one at https://typesafe.ai
npx supercov quality

No arguments and no configuration. It finds your source, ask