cc2cx

Convert Claude Code sessions into Codex rollout files so they appear in codex resume.

Why

We all know that Claude is better at some things and Codex is better at others. If you switch between them or want to reference a Claude Code session from Codex's /resume picker, this tool bridges the gap. It reads a Claude Code session JSONL, converts messages/tool calls/reasoning into Codex's rollout format, and registers the result so Codex discovers it.

Install

bun install -g cc2cx

Or run directly without installing:

bunx cc2cx <session-id|last>

npx cc2cx and npm install -g cc2cx work too.

Requires Node.js 18+ and a native compilation toolchain for better-sqlite3.

Usage

cc2cx <session-id|last> [options]

Arguments:

• session-id -- UUID of a Claude Code session (e.g. 862e1482-b9cb-49ad-8631-e297a82463e0)
• last -- automatically picks the most recently modified session across all projects

Options:

| Flag | Description | |------|-------------| | --dry-run | Print converted JSONL to stdout without writing any files | | --no-register | Write the rollout file but skip history.jsonl and SQLite registration | | --project PATH | Limit session search to a specific Claude Code project path | | --verbose | Print conversion stats (turns, lines, file paths) |

Examples

Convert the most recent Claude Code session:

cc2cx last

Preview what would be generated without writing anything:

cc2cx last --dry-run

Convert a specific session with verbose output:

cc2cx 862e1482-b9cb-49ad-8631-e297a82463e0 --verbose

After running, open Codex and the session will appear in the /resume list.

What it does

1. Resolves the Claude Code session file from ~/.claude/projects/
2. Parses the JSONL, deduplicating streamed assistant messages and walking the linked-list message chain
3. Segments messages into turns (each user message starts a new turn)
4. Converts each turn into Codex's rollout format:
   • session_meta header
   • response_item entries for user/assistant messages, reasoning, and tool calls
   • event_msg entries for turn lifecycle (task_started, task_complete, etc.)
   • turn_context metadata
5. Writes the rollout file to ~/.codex/sessions/YYYY/MM/DD/
6. Registers the session in ~/.codex/history.jsonl and ~/.codex/state_5.sqlite so it appears in /resume

Tool mapping

Claude Code tools are translated to their Codex equivalents:

| Claude Code | Codex | |-------------|-------| | Bash | exec_command | | Read | exec_command (as cat -n) | | Edit | exec_command (as apply_patch) | | Write | exec_command (as cat >) | | Grep | exec_command (as rg) | | Glob | exec_command (as rg --files) | | WebSearch, WebFetch | exec_command (as comment) | | mcp__* | Passed through unchanged | | ToolSearch | Skipped |

Limitations

• Subagent/team sessions are not converted (main session only)
• Image content blocks are dropped
• Token counts are not reconstructed
• Thinking blocks are emitted as plaintext reasoning summaries

License

MIT