codex-discord-mcp

A local-first Discord bridge for Codex CLI.

Use it in three ways:

1. Discord -> Codex: mention or DM your bot, run codex exec --json, and post the final answer back to Discord.

2. Codex -> Discord: expose Discord tools to Codex through MCP, including reply, fetch_messages, react, edit_message, download_attachment, latest_generated_images, and recover_generated_image.

3. Hybrid workflow: receive Discord messages into a local queue, then let Codex inspect and respond through MCP tools.

This is not an official OpenAI plugin. It is a local bridge designed around Codex CLI, MCP, and Discord bot APIs.

Which Mode Should I Use?

Related MCP server: discord-mcp-agent

Security Model

This bridge treats Discord as untrusted input.

Discord users cannot:

• approve pairings

• allow users

• allow channels

• change bridge policy

• read bridge state files

• bypass Codex sandbox or approval settings

Only local terminal commands can change access policy. MCP tools can read and reply through allowlisted Discord channels, but they cannot modify the allowlist or approve pairings.

Default safety posture:

• Default sandbox: read-only

• Default approval policy: never, because bot mode is non-interactive

• Recommended first run: read-only

• Use workspace-write only in an isolated repository or disposable worktree

• Never use danger-full-access for a public Discord channel

When bot mode starts with CODEX_SANDBOX=workspace-write or CODEX_SANDBOX=danger-full-access and CODEX_APPROVAL_POLICY=never, the bridge prints a runtime warning. Set CODEX_DISCORD_ASSUME_YES=true to suppress the warning in controlled automation.

Requirements

• Node.js 20 or newer.

• Codex CLI installed and authenticated for bot mode.

• A Discord application with a bot token.

• Discord bot privileged Message Content Intent enabled.

Install

Global install:

npm install -g codex-discord-mcp
codex-discord-mcp doctor
codex-discord-mcp init

Run through npx without a global install:

npx -y codex-discord-mcp doctor

Local development install:

npm install
npm run build
node ./dist/cli.js --help

Discord Bot Setup

1. Create a Discord application in the Discord Developer Portal.

2. Add a bot and copy its token.

3. Enable Message Content Intent for the bot.

4. Invite the bot to a server if you want guild channels.

Useful bot permissions:

• View Channels

• Send Messages

• Send Messages in Threads

• Read Message History

• Attach Files

• Add Reactions

Print an invite URL:

codex-discord-mcp invite-url <client-id>

Store the token locally:

codex-discord-mcp configure

The token is written to ~/.codex/discord/.env by default. Override the state directory with CODEX_DISCORD_STATE_DIR.

You can also read the token from an existing environment variable:

codex-discord-mcp configure --token-env DISCORD_BOT_TOKEN

Quick Start

Interactive setup:

codex-discord-mcp init

Check local configuration:

codex-discord-mcp doctor
codex-discord-mcp doctor --json

Mode 1: Discord To Codex Relay

Run:

codex-discord-mcp bot

Default behavior:

• Unknown DM users receive a one-hour pairing code.

• Pair locally with codex-discord-mcp access pair <code>.

• After pairing, each DM message triggers codex exec --json.

• The final Codex message is posted as a Discord reply.

• Files the run produced are attached to that reply automatically (see below).

Useful environment variables:

export CODEX_WORKDIR="/path/to/repo"
export CODEX_SANDBOX="read-only"
export CODEX_APPROVAL_POLICY="never"
export CODEX_RESUME_BY_CHANNEL="true"
codex-discord-mcp bot

For unattended relay mode, keep CODEX_APPROVAL_POLICY=never and use the least permissive sandbox that fits the channel.

Relay File Delivery

bot mode delivers files, not just text, on by default (CODEX_DISCORD_RELAY_ATTACHMENTS=false disables both paths):

• Generated images. Codex's built-in image_gen usually writes no file to disk; the image survives only as base64 inside the session rollout. The relay records the rollout size before each run and, after the run, decodes any image_generation_call results appended past that offset — so it attaches exactly the images this run generated, even on long resumed threads, without re-reading the whole rollout.

• Outbox deliverables. The prompt tells Codex to save user-facing files under a per-channel outbox directory (CODEX_DISCORD_OUTBOX_DIR, default ~/.codex/discord_outbox/<channel-id>/). Document, data, archive, and media files written there during the run are attached to the reply; code files, logs, and dotfiles are ignored.

Attachments respect Discord limits: at most 10 files per reply, 25MB each. If attaching fails, the relay retries text-only so the answer itself is never lost.

Mode 2: Codex MCP Tools

Print a local config snippet:

codex-discord-mcp print-config

Print an npx based config snippet:

codex-discord-mcp print-config --npx

Add the snippet to ~/.codex/config.toml or a trusted project .codex/config.toml. A typical npx config looks like:

[mcp_servers.discord]
command = "npx"
args = ["-y", "codex-discord-mcp", "mcp"]
startup_timeout_sec = 20
tool_timeout_sec = 60

Then start Codex and run /mcp to confirm the Discord tools are loaded.

Available MCP tools:

Access Control

Access is managed by local CLI commands, not MCP tools.

codex-discord-mcp access show
codex-discord-mcp access policy allowlist
codex-discord-mcp access allow-user 123456789012345678
codex-discord-mcp access allow-channel 234567890123456789
codex-discord-mcp access allow-channel 234567890123456789 --no-mention

DM policy values:

• pairing: unknown DM users get a one-hour pairing code. This is the default.

• allowlist: unknown DM users are silently ignored.

• disabled: all DMs are ignored.

Guild channels are opt-in by channel ID. By default, the bot only responds in an allowed guild channel when it is mentioned or when the user replies to a recent bot message. Use --no-mention only for dedicated bot channels.

Attachment Safety

The bridge refuses to attach its own state files, except files downloaded into the inbox. It also blocks attachment paths outside the configured attachment roots.

Attachment uploads are restricted by default to:

• the bridge process working directory

• CODEX_WORKDIR

• the bridge inbox

• Codex's built-in image_gen output directory (~/.codex/generated_images, or CODEX_DISCORD_GENERATED_IMAGES_DIR)

• the relay outbox (~/.codex/discord_outbox, or CODEX_DISCORD_OUTBOX_DIR)

The image_gen output directory is always allowed so generated images can be attached. Codex's built-in image_gen shows an inline preview but often writes no file to disk — in that case call recover_generated_image, which decodes the just-generated image from the active session rollout and saves it to the image_gen output dir, returning the absolute path. (latest_generated_images lists already-saved image files.) Then pass the path in the files array of reply/send_message.

To allow generated files from other roots, set CODEX_DISCORD_ATTACHMENT_ROOTS using your platform path delimiter:

export CODEX_DISCORD_ATTACHMENT_ROOTS="/path/to/repo:/path/to/exports"

On Windows PowerShell:

$env:CODEX_DISCORD_ATTACHMENT_ROOTS="C:\path\to\repo;C:\path\to\exports"

Configuration Reference

Troubleshooting

codex-discord-mcp doctor
codex-discord-mcp access show

If the bot receives empty message content, enable Message Content Intent in the Discord Developer Portal.

If bot mode cannot launch Codex, set CODEX_COMMAND to the full executable path or run the bridge from the same shell where codex exec "hello" works.

If MCP tools do not appear, run:

codex-discord-mcp print-config --npx

Then add the printed snippet to Codex config and restart Codex.

Development

npm install
npm run typecheck
npm test
npm run build

Development commands:

npm run dev:mcp
npm run dev:bot

Release

The package is prepared for npm publishing with:

• bin entry: codex-discord-mcp

• files whitelist for published package contents

• prepublishOnly validation: typecheck, tests, build

• Linux and Windows GitHub Actions CI