migrate-to-codex

migrate-to-codex is a migration tool that converts supported Claude Code configuration — instruction files, slash commands/skills, subagents, hooks, and MCP server config — into the equivalent Codex project and global files (AGENTS.md, .codex/, .agents/, ~/.codex/). It solves the problem of moving a working Claude Code setup onto Codex without hand-porting each surface, and it maps sources to targets explicitly (for example .claude/agents to .codex/agents, .mcp.json to .codex/config.toml MCP servers, .claude/settings.json hooks to .codex/hooks.json).

The skill drives a Python migrator with inspection-first flags — `--scan-only`, `--plan`, `--doctor`, and `--dry-run` — before writing anything, then converts surfaces in a fixed order and validates the generated config and agents with `--validate-target`. It reads a `references/differences.md` guide to account for Claude-vs-Codex behavior gaps, reports plugins and marketplaces as manual-review work, and produces a final markdown migration report per scope. It is designed to run autonomously once a target is selected: it will create, edit, replace, or delete generated Codex artifacts in that target without pausing for confirmation, using `--replace` to remove orphaned generated skills or agents. Importantly, it is constrained to only touch generated Codex files and explicitly must not edit source Claude Code files, unrelated project code, secrets, or other repositories, and it preserves unrelated existing Codex config entries.

It targets developers moving from Claude Code to Codex. The main thing to be aware of is its autonomous file writing and deletion within the chosen target directories, which is scoped to migration-generated artifacts rather than arbitrary files.