chock-copilot-plugins

Blocks your Copilot agent's wrong moves before they land.

Chock policies for Copilot CLI and VS Code agent mode — a real PreToolUse deny hook where the client supports it.

An agent you're running can already touch your shell, your git history, and your CI config. You want it to move fast without being the reason a stray rm -rf actually happens. Telling it to be careful in a prompt is not a guarantee; a plugin that can refuse the command is closer to one — and it should be honest about which of those two it is.

Two ways to get these plugins

This marketplace: no chock on the machine. Each policy is its own plugin, republished with every chock release. You need Python 3.11+, git and a bash (Git for Windows includes one). Add this repository as a plugin marketplace in VS Code / GitHub Copilot, then install a plugin by name. See the Copilot plugins marketplace and VS Code's agent-plugins docs:

• https://github.com/github/copilot-plugins
• https://code.visualstudio.com/docs/agent-customization/agent-plugins

These packages use the Claude plugin format, which VS Code and GitHub Copilot CLI read natively (VS Code auto-detects the format and sets CLAUDE_PLUGIN_ROOT for the hook).

The builder: one plugin, needs chock. Pick the policies you want at chock.sh; it writes one chock install command that builds a single plugin on your machine from chock-catalog. That command needs pip install chock:

pip install chock
chock install --selection <code> --client copilot --apply

Use one route for a given policy, never both. Every copy of a plugin runs its own hook, so a policy installed from both places runs twice. To switch a policy from one route to the other, remove it from the first route before installing it from the second:

1. Remove each plugin you installed from the chock marketplace. In Copilot CLI: copilot plugin uninstall <id>@chock. In VS Code: /plugin uninstall <id>@chock in agent mode.
2. To drop the marketplace too: copilot plugin marketplace remove chock in Copilot CLI, /plugin marketplace remove chock in VS Code.

Builder links, one policy at a time

Each link opens the builder with that one policy preselected for Copilot, pinned to chock-catalog commit e885f918a335e20dfddb4fad0331d4d5b4c5eb43 (the catalog's main on 2026-10-21). The pin is the catalog's current version of each policy, which can be newer than the version listed in PLUGINS.md.

policy	in Copilot	builder
agent-discipline	advisory	open in the builder
block-curl-pipe-sh	enforces	open in the builder
block-destructive-commands	enforces	open in the builder
block-invisible-unicode	enforces	open in the builder
block-no-verify	enforces	open in the builder
block-test-skips	enforces	open in the builder
block-unapproved-egress	enforces	open in the builder
block-unguarded-agent-spawn	enforces	open in the builder
block-wildcard-agent-permissions	enforces	open in the builder
chock-mise	advisory	open in the builder
code-safety	advisory	open in the builder
context-hygiene	advisory	open in the builder
firecrawl-fallback-only	advisory	open in the builder
git-safety	advisory	open in the builder
guard-memory-writes	enforces	open in the builder
injection-defense	advisory	open in the builder
java-security	enforces	open in the builder
limit-diff-size	advisory	open in the builder
memory-discipline	advisory	open in the builder
no-a11y-regression	enforces	open in the builder
pin-github-actions	enforces	open in the builder
protect-agent-config	enforces	open in the builder
protect-ci-workflows	enforces	open in the builder
protect-commit-privacy	enforces	open in the builder
protect-main-branch	advisory	open in the builder
protect-test-integrity	enforces	open in the builder
rtk-dangerous-actions-blocker	enforces	open in the builder
scan-secrets	enforces	open in the builder
token-efficiency	advisory	open in the builder
verify-dependency-exists	enforces	open in the builder
verify-mcp-allowlist	enforces	open in the builder

Generated from chock-catalog

Every file here is compiled from policy sources in chock-catalog by chock. Pull requests against this repository are closed automatically — open them against the catalog instead.

• Generated only: CI regenerates from the pinned catalog and fails on any difference.
• Byte-identical guards: each guard script is a verbatim copy of its policy's source in the catalog, and the hook adapter a verbatim copy of its framework source.
• Best-effort, not a boundary: guards are pattern-based filters; see SECURITY.md.
• Tested upstream, and gated: every policy ships an eval suite (base/<policy>/evals/suite.yaml) in the catalog, and the publish workflow runs chock check and chock check --only evals before packaging anything — a policy whose evals fail cannot reach this repository. The tests live in the catalog because the policy source does; this repository is compiled output.
• This README is hand-written, as are SECURITY.md and the workflows under .github/, so they sit outside the generated-only guarantee.

Verify it yourself

Nothing above asks for trust that cannot be checked. This rebuilds the published tree from source and compares it with what is committed here:

git clone https://github.com/open-coder-ai/chock-copilot-plugins dist
git clone https://github.com/open-coder-ai/chock-catalog catalog
git clone --branch "$(tr -d '[:space:]' < catalog/.framework-ref)" \
  https://github.com/open-coder-ai/chock framework
pip install ./framework
chock plugin build --repo catalog --policies-dir base --format agent-plugins --out-dir dist
chock plugin build --repo catalog --policies-dir base --format claude --out-dir dist
chock plugin build --repo catalog --policies-dir base --format copilot --out-dir dist
chock marketplace build --dist dist
git -C dist diff --exit-code && git -C dist status --porcelain

Silence from both git commands means this repository is byte-identical to a fresh build from the catalog. The framework ref comes from the catalog's own .framework-ref, which is what the publish and Generated-only workflows read, so this recipe cannot drift from the release a tree was actually built with. chock-market.lock records a sha256 per published plugin directory, so one package can be checked without rebuilding the rest.

If you are listing these plugins in a marketplace, pin both a tag and the full commit SHA. The tag names the release; the SHA is what holds the reviewed bytes still.

Contributing

You want to	Go to
Fix or add a policy	chock-catalog — it reaches every client from there, including this one
Report that a guard did or did not block on your Copilot CLI or VS Code version	an issue on chock, which records what each package claims. No package here carries a witnessed block yet — the claims are read from vendor documentation — so a first-hand "it blocked" or "it fails open where you say it fails closed" is the most useful result you can send
Report a bug in how packages are generated	chock, where the emitter lives
Fix this README	here — it is hand-written, not generated

Part of open-coder-ai

agentseam	the primitives — one handler API and a verified capability matrix across 16 agents
chock	the compiler — one policy into git hooks, CI gates and native pre-tool hooks
chock-catalog	the policies — 42, each labelled enforced or advisory, with replayed evals
context-report	the evidence — a signed report of whether an agent artifact actually works
chock-threat-intel	the threat ledger the catalog's policies answer to
chock-{claude,cursor,copilot,codex}-plugins	the catalog, packaged for each agent's plugin format (generated)
chock-quickstart · chock-example	template repos: what chock init leaves behind, and a full adoption

License

Apache-2.0, same as the framework and the catalog.