Codex Sublime Text plug-in

Chat with the Codex CLI directly from Sublime Text.

Upgrade Notes

• Markdown and folding: The transcript and input panels now use a bundled Markdown syntax for improved headings and section folding. You can auto‑fold sections by header via fold_sections in project or global Codex settings. The plug-in spins up a codex app-server subprocess, shows the conversation in a Markdown panel, and integrates approvals/sandboxed execution directly in the Sublime UI.

Features

• Full Codex capabilities
  • Assistant-to-Bash interaction
  • Sandboxing (on macOS and Linux)
  • Model and provider selection
• MCP support (via ~/.codex/config.toml)^1
• Deep Sublime Text integration
  • Multiline input field uses Markdown
  • Selected text is auto-copied into the message with syntax applied
  • Outputs to either the output panel or a separate tab
  • Symbol list included in answers
• Works out of the box[^2].

Installation

1. Download Separate Codex instance (the plug-in talks to the CLI, it is not bundled) from codex releases matching this plugin release (for 1.147.1, use codex-cli 0.147.0).

Point out the downloaded codex binary from within plugin settings:

{
  "codex_path": ["~/some_path/codex"],
}

2. Plugin installation

   1. With Package Control Package Control: Install Package → Codex

   2. Manual Clone / download into your Packages folder (e.g. ~/Library/Application Support/Sublime Text/Packages/Codex).

3. Sign in with Codex CLI (codex login) if you are not already authenticated.

That’s it – hit ⌘⇧P / Ctrl ⇧ P, type Codex, select one of the commands and start chatting.

Commands (⌘⇧P)

• Codex: New Message – open a small Markdown panel, type a prompt, hit Super+Enter. At the start of the input, use Up/Down to browse earlier prompts; Escape keeps the unfinished draft for the next time the panel opens.
• Codex: Open Transcript Tab – open the conversation buffer in a normal tab.
• Codex: Reset Chat – stop the Codex subprocess, clear the transcript and invalidate the stored session_id so the next prompt starts a brand-new session.

Per-project configuration

Every Sublime project can override Codex settings under the usual settings section. Example:

{
    "folders": [{ "path": "." }],

    "settings": {
        "codex": {
            // will be filled automatically – delete or set null to reset
            "session_id": null,

            // model & provider options
            // leave empty to use the model selected by your Codex account
            "model":            "",
            "provider_name":    "openai",
            "base_url":         "https://api.openai.com/v1",
            "wire_api":         "responses",
            "approval_policy":  "on-failure",

            // sandbox
            "sandbox_mode": "read-only",
            "permissions": [
                // additional writable paths (project folders are added automatically)
                "/Users/me/tmp-extra"
            ]
            ,
            // Auto-fold specific sections in the transcript by their header
            // name (case-insensitive). You can pass a string or a list.
            // Example: fold the model's internal reasoning block
            // (rendered as "## agent_reasoning").
            "fold_sections": ["agent_reasoning"]
        }
    }
}

What is sent to Codex

The plugin launches codex app-server with CLI --config overrides derived from global/per-project Sublime settings, including:

• model
• sandbox_mode
• approval_policy
• sandbox_workspace_write.network_access
• sandbox_workspace_write.writable_roots

If a value is not overridden by the plugin, Codex falls back to its normal global config (~/.codex/config.toml).

For workspace-write, project folders and optional settings.codex.permissions are propagated as writable roots.

Enjoy hacking with Codex inside Sublime Text! 🚀

Code sent to the language model

The plugin only sends the code snippets that you explicitly type or select in the input panel to the language model. It never uploads your entire file, buffer, or project automatically. Local configuration (such as sandbox permissions or project folders) is used only by the CLI to enforce file I/O rules and is not included in the prompt context.

However keep in mind that since this plugin and tool it relays on is agentish, any data from within your sandbox area could be sent to a server.

Suppressing noisy events

If the Codex backend floods the transcript with incremental updates such as agent_reasoning_delta, add them to the suppress_events array in your project-specific codex settings:

{
  "suppress_events": ["agent_reasoning_delta"]
}

Auto-folding sections

You can tell the transcript to auto‑fold certain sections by header name. The match is case-insensitive and can be configured globally or per-project.

• Global (Preferences ▸ Package Settings ▸ Codex ▸ Settings):

  {
    // ... other settings ...
    "fold_sections": ["agent_reasoning"]
  }
  

• Per project (.sublime-project under settings.codex):

  {
    "settings": {
      "codex": {
        "fold_sections": ["agent_reasoning"]
      }
    }
  }
  

Notes

• Folding is scope-based and targets the Markdown meta.section for that header. Only the section body is folded, so the header line shows with an inline ellipsis (row style), e.g.: ## agent_reasoning ....
• The fold is applied right after the section is appended. If your syntax definition delays section scopes, the plugin waits briefly to target the correct section.

Development

Shared chat UI

Panel primitives and the fixed Chat Markdown syntax are vendored from the public sublime-chat-ui source repository. Edit that repository, then update this read-only subtree with:

./scripts/update_sublime_chat_ui.sh <ref>

Set SUBLIME_CHAT_UI_REPO to a local clone path to pull unpushed development branches.

[^2]: If codex is installed and authenticated (for example via codex login).