codex/agentydragon/CHANGES.md

codex-rs: Changes between HEAD and main

This document summarizes new and removed features, configuration options, and behavioral changes in the codex-rs workspace between the main branch and the current HEAD. Only additions/deletions (not unmodified code) are listed, with examples of usage and configuration.

---

CLI Enhancements

Build & Install from Source

cargo install --path cli --locked
# install system-wide:
sudo cargo install --path cli --locked --root /usr/local

New codex config Subcommand

Manage your ~/.codex/config.toml directly without manually editing:

codex config edit            # open config in $EDITOR (or vi)
codex config set KEY VALUE   # set a TOML literal, e.g. tui.auto_mount_repo true

New codex inspect-env Command

Inspect the sandbox/container environment (mounts, permissions, network):

codex inspect-env --full-auto
codex inspect-env -s network=disable -s mount=/mydir=rw

Resume TUI Sessions by UUID

codex session <SESSION_UUID>

MCP Server (JSON‑RPC) Support

Launch Codex as an MCP server over stdin/stdout and speak the Model Context Protocol (JSON-RPC):

npx @modelcontextprotocol/inspector codex mcp

Sample JSON‑RPC Interaction

// ListTools request
{ "jsonrpc": "2.0", "id": 1, "method": "tools/list", "params": {} }

// CallTool request
{ "jsonrpc": "2.0", "id": 2, "method": "tools/call",
  "params": { "name": "codex", "arguments": { "prompt": "Hello" } }
}

// CallTool response (abbreviated)
{ "jsonrpc": "2.0", "id": 2, "result": {
    "content": [ { "type": "text", "text": "Hi there", "annotations": null } ],
    "is_error": false
}}

---

Configuration Changes

auto_allow Predicate Scripts

Automatically approve or deny shell commands via custom scripts:

[[auto_allow]]
script = "/path/to/approve_predicate.sh"
[[auto_allow]]
script = "my_predicate --flag"

Vote resolution:

• A deny vote aborts execution.
• An allow vote auto-approves.
• Otherwise falls back to manual approval prompt.

base_instructions_override

Override or disable the built-in system prompt (prompt.md):

export CODEX_BASE_INSTRUCTIONS_FILE=custom_prompt.md   # use custom prompt
export CODEX_BASE_INSTRUCTIONS_FILE=""             # disable base prompt

TUI Configuration Options

In ~/.codex/config.toml, under the [tui] table:

editor          = "${VISUAL:-${EDITOR:-nvim}}"  # external editor for prompt
message_spacing = true                           # insert blank line between messages
sender_break_line = true                         # sender label on its own line

---

Core Library Updates

System Prompt Composition Customization

System messages now combine:

1. Built-in prompt (prompt.md),
2. User instructions (AGENTS.md/instructions.md),
3. apply-patch tool instructions (for GPT-4.1),
4. User command/prompt.

Controlled via CODEX_BASE_INSTRUCTIONS_FILE.

Chat Completions Tool Call Buffering

User turns emitted during an in-flight tool invocation are buffered and flushed after the tool result, preventing interleaved messages.

SandboxPolicy API Extensions

policy.allow_disk_write_folder("/path/to/folder".into());
policy.revoke_disk_write_folder("/path/to/folder");

Auto‑Approval Predicate Engine

use codex_core::safety::{evaluate_auto_allow_predicates, AutoAllowVote};
let vote = evaluate_auto_allow_predicates(&cmd, &config.auto_allow);
match vote {
    AutoAllowVote::Allow => /* auto-approve */, 
    AutoAllowVote::Deny => /* reject */, 
    AutoAllowVote::NoOpinion => /* prompt user */, 
}

---

TUI Improvements

Double Ctrl+D Exit Confirmation

Prevent accidental exits by requiring two Ctrl+D within a timeout:

use codex_tui::confirm_ctrl_d::ConfirmCtrlD;
let mut confirm = ConfirmCtrlD::new(require_double, timeout_secs);
// confirm.handle(now) returns true to exit, false to prompt confirmation

Markdown & Header Compact Rendering

New rendering options (code-level) for more compact chat layout:

• markdown_compact
• header_compact

---

Documentation & Tests

• codex-rs/config.md, codex-rs/README.md, core/README.md updated with examples.
• New core/init.md guidance for generating AGENTS.md templates.
• Added tests for codex config, ConfirmCtrlD, and evaluate_auto_allow_predicates.