Codex MCP plugin + Pre-Action Checks

# Give Codex a thumbs-down once. Block the repeat before it runs again.

Updated: 2026-04-20 · by Igor Ganapolsky

ThumbGate wires Codex into local-first feedback memory, MCP tools, and hook enforcement. The launcher resolves `thumbgate@latest` when Codex starts, so published npm fixes reach your active MCP server after a restart.

Download Codex plugin Read install docs Use CLI setup

    $ npx thumbgate init --agent codex
    # Writes ~/.codex/config.toml and ~/.codex/config.json
    # MCP + hooks install thumbgate@latest before serving or checking gates

### Always-on when enabled

If Codex settings show the `thumbgate` MCP server toggled on, Codex can call the local ThumbGate tools. Typed feedback still needs useful context before it becomes a durable rule.

### Latest runtime on restart

The Codex launcher installs `thumbgate@latest` into `~/.thumbgate/runtime` before running MCP or gate checks. A new npm publish reaches Codex after the app restarts.

### Hard stop before action

Pre-Action Checks evaluate commands, file edits, publishes, merges, and other high-risk actions before execution. Bad repeats get blocked before they burn time or tokens.

What Codex gets

## MCP memory, hook checks, and a dashboard lane in the same install path.

Use the standalone plugin when you want a portable Codex bundle. Use `npx thumbgate init --agent codex` when you want the shortest path on this machine. Both paths point at the same Reliability Gateway and the same npm runtime.

The Codex launcher checks npm on startup. Restart Codex after a ThumbGate publish to let the MCP server and hook bundle pick up the latest runtime.

Codex test lane after ThumbGate writes MCP, PreToolUse, UserPromptSubmit, PostToolUse, SessionStart, and the status line target.
Install flow

## Three paths. Same local gateway.

### 1. Automatic setup

Run `npx thumbgate init --agent codex`. ThumbGate writes the MCP server block and hook bundle into your Codex config files.

### 2. Standalone plugin

Use the release bundle when Codex loads plugin surfaces directly. The bundle includes the manifest, MCP config, marketplace entry, and install docs.

### 3. Verify in Codex

Open Codex settings, confirm `thumbgate` is toggled on, then restart Codex after npm releases to pick up the latest runtime.

### Pro only after proof

Use the free Codex path to prove one real blocked repeat first. Upgrade to Pro only when you want the personal dashboard, proof-ready exports, and a review surface after that proof exists.

### Commercial truth stays inspectable

Pricing, traction guardrails, and what must not be claimed live in the Commercial Truth document, not in launch copy or vibes.

### Team motion starts with one workflow

If your buyer already named one repeated workflow failure, one owner, and one approval boundary, route them to the Workflow Hardening Sprint instead of a generic plugin pitch.

Operator questions

## What happens when I click thumbs up or thumbs down?

### Is the MCP server always on?

It is on when the Codex MCP settings toggle is enabled and the configured command can start successfully. In the Codex app, the blue toggle next to `thumbgate` is the visible check.

### Does bare feedback become a rule?

No. Bare "thumbs down" is intentionally too vague for memory promotion. Add one concrete sentence about what went wrong, the file, command, or behavior to block next time.

### Where is the direct asset?

The standalone zip remains available at GitHub Releases. This page is the human install surface so users do not land on an unexplained file download.