Warden proves guardrails.

Build a hoop guardrail regex from a query you want blocked, test it live against your own examples, and export it ready to enforce. Everything runs in this page; your queries never leave the browser.

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Start from a query.

Paste a query you want to block, plus an optional similar one that must stay allowed. Warden recognizes the shapes and suggests vetted rules, pre-filled from the queries themselves.

Shape it, then prove it.

Pick a vetted template, write raw RE2 or list deny words. Every example on the bench reruns on each keystroke, and the export updates with it.

Rule

Pattern rules match the text of a query and cannot parse SQL. A rule that passes each test here can still be evaded by a rewritten query (CTEs, subqueries, obfuscated conditions). Pair guardrails with review for high-risk access.

Test bench

Matching runs in your browser with RE2, the portable subset both of hoop's guardrail engines accept. It proves behavior on these examples only; untested queries are untested.

Must be blocked

no examples

    Must be allowed

    no examples

      Export

      Build a rule first; the exports appear here.

      Author, prove, enforce.

      The page and the CLI run the same RE2 engine, so a rule proven here is proven in CI.

      1. Author

        Paste a query you want blocked, pick a vetted template, or write raw RE2. Or let an LLM draft it on the command line.

        warden generate -block "DELETE without WHERE"

      2. Prove

        The test bench runs every example through the same RE2 engine hoop compiles. In CI, the CLI does the same and fails the build on any regression.

        warden test rules/*.yaml

      3. Enforce

        Export a ready-to-run curl that creates the guardrail through hoop’s API, then attach it to your connections.

        curl -X POST .../api/guardrails

      More from hoop Labs.

      Each tool solves one problem, runs locally and needs no signup to try.

      See every labs tool

      hoop enforces the whole policy.

      One rule blocks one query shape. Guardrails, data masking, access control and full audit logs, enforced centrally across every agent, every connection and every protocol. That is the hoop.dev platform.

      Get started freeView on GitHub (opens in a new tab)

      Ask an assistant what hoop.dev does: Claude, ChatGPT, Grok, Gemini, Perplexity, Copilot.

      the Warden CLI
      $ brew install hoophq/tap/warden
# prove rules in CI
$ warden test rules/*.yaml
# draft a rule with an LLM
$ warden generate -block "DELETE without WHERE"