Catalog
openai/migrate-to-codex

openai

migrate-to-codex

Migrate supported instruction files, skills, agents, and MCP config into Codex project and global files.

global
New~2.0k
v1.1Saved Jun 4, 2026

Migrate to Codex

Autonomy

Keep going until the selected migration is completely done: run the migrator, inspect the report, fix migrated Codex instructions/skills/agents/MCP config, and re-run checks without stopping to ask for confirmation of the next step. If the user has selected a target, do not ask before creating, editing, replacing, or deleting generated Codex artifacts in that target (AGENTS.md, .codex/, .agents/, or ~/.codex/). Preserve unrelated existing Codex config entries in .codex/config.toml or ~/.codex/config.toml, such as notify, projects, marketplaces, or unrelated MCP servers; do not ask about them unless they fail validation or directly conflict with the migration. Do not edit source Claude Code files (.claude/, ~/.claude/, .mcp.json, or .claude.json), unrelated project code, secrets, or another repository.

Migration Order

Run the migration in this order for each selected global or project source:

  1. Start by using Codex's built-in TODO/task list tool. Do not create MIGRATION_TODOS.md or any TODO file unless the user explicitly asks. The TODO list input has a plan array whose items each have step and status; use statuses pending, in_progress, and completed. Make the TODOs specific to the selected artifacts. Before finishing, update the TODO list so every finished step is marked completed and no step remains in_progress. Use literal source → Codex target labels, for example:

    • Inspect .claude/commands → Codex skills/prompts
    • Inspect .claude/agents.codex/agents
    • Inspect .mcp.json.codex/config.toml MCP servers
    • Inspect .claude/settings.json hooks → .codex/hooks.json
    • Migrate safe selected artifacts → Codex files
    • Validate generated .codex/config.toml
    • Validate generated .codex/agents
    • Report migrated artifacts and manual-review items
  2. Read references/differences.md (and refresh Codex docs if its Docs last checked date is old).

  3. Scan and inspect before writing:

    • --scan-only lists active and inactive source surfaces.
    • --plan prints staged Codex artifact paths and report rows.
    • --doctor summarizes readiness, manual-review work, and validation risks.
  4. Convert surfaces in the same order the CLI uses:

    • instructions: CLAUDE.md / AGENTS.md to AGENTS.md
    • plugins: report Claude plugin trees and marketplaces as manual migration work
    • hooks: rewrite supported Claude hooks into .codex/hooks.json and enable [features].codex_hooks = true
    • skills and commands: write Codex skills under .agents/skills/
    • config: write .codex/config.toml from Claude model/sandbox settings and MCP servers, including personality = "friendly" when config is generated
    • subagents: write Codex custom agents under .codex/agents/
  5. Dry-run, then write the selected target. Use --replace only when orphan generated skills or agents should be deleted.

  6. Inspect the terminal output and .codex/migrate-to-codex-report.txt after real runs.

  7. Review generated artifacts in this order: AGENTS.md, .agents/skills/, .codex/config.toml, .codex/hooks.json, .codex/agents/, then report-only plugin items.

  8. Run --validate-target against each target after edits.

  9. Re-run checks and --dry-run after edits.

  10. Return the final migration report as one markdown table per scope that has rows. The tables cover only the non-native follow-up migration work you performed, such as skills created from slash commands, subagents, MCP servers, hooks, unsupported/local plugin notes, and manual-review caveats. Include programmatic native import rows for config, instructions, skills, or supported plugins only if you personally migrated them in this follow-up run.

    If only one scope has rows, render only the table with no heading. If multiple scopes have rows, render one heading before each table. Use **User Config** for user-scope rows. For project-scope rows, use the actual project folder name as the heading, for example **northstar-support-portal**; do not use Current Project as the heading. Do not add prose before or after the table output.

    Use exactly these columns:

    northstar-support-portal

    Status Item Notes
    Added Slash command pr-review Converted into a Codex skill
    Added Subagent release-lead Added as a Codex subagent
    Check before using Hook PreToolUse Converted, but some Claude hook behavior differs in Codex
    Not Added Hook Notification Codex does not have an equivalent notification hook
    Not Added Plugin team-macros Plugin needs manual setup

    Status must be Added, Check before using, or Not Added. Use Added when a Codex-facing artifact was created or changed and needs no special review. Use Check before using when a Codex-facing artifact was created or changed but the migration changed semantics, inferred behavior, preserved tool rules as guidance, or dropped unsupported behavior. Use Not Added when a source artifact was detected but no Codex-facing artifact was created. Item combines the artifact type and concrete item name in one cell. Artifact type must be singular: Skill, Slash command, Subagent, MCP, Hook, or Plugin. Wrap the artifact type in inline code; write the item name as plain text after it. Notes is always required; never leave it empty. Keep notes short, plain, and literal. Avoid internal implementation terms such as runtime expansion. Prefer phrases like Converted into a Codex skill, Added as a Codex subagent, Added to Codex config, Converted into a Codex hook, Converted, but some Claude hook behavior differs in Codex, Codex does not have an equivalent notification hook, Plugin needs manual setup, or Plugin marketplace needs manual setup.

Self-Healing Loop

Keep looping until the selected migration is complete:

  1. Run --plan or --doctor.
  2. Run the migration with --dry-run.
  3. Run the migration for real.
  4. Fix every generated ## MANUAL MIGRATION REQUIRED block and every manual_fix_required or skipped report row that can be resolved inside Codex artifacts.
  5. Run --validate-target.
  6. Re-run the migrator and validator until the report and validator have no actionable generated-artifact fixes left.

Do not edit source Claude Code files, unrelated project code, secrets, or another repository during this loop. If a report row requires source-provider changes or product judgment, leave the generated Codex artifact with clear manual guidance instead of changing the source.

Commands

Choose the migrator command.

MIGRATE_TO_CODEX='python3 .codex/skills/migrate-to-codex/scripts/migrate-to-codex.py'

Inspect the migration before writing.

$MIGRATE_TO_CODEX --source ~/.claude/ --scan-only
$MIGRATE_TO_CODEX --source ~/.claude/ --target ~/.codex/ --plan
$MIGRATE_TO_CODEX --source ~/.claude/ --target ~/.codex/ --doctor

Dry-run, then run without --dry-run, for global and project.

$MIGRATE_TO_CODEX --source ~/.claude/ --target ~/.codex/ --dry-run
$MIGRATE_TO_CODEX --source ~/.claude/ --target ~/.codex/
$MIGRATE_TO_CODEX --source ./.claude/ --target ./.codex/ --dry-run
$MIGRATE_TO_CODEX --source ./.claude/ --target ./.codex/

Run the post-migration validator against each target after edits.

$MIGRATE_TO_CODEX --validate-target ~/.codex/
$MIGRATE_TO_CODEX --validate-target ./.codex/

Run $MIGRATE_TO_CODEX --help for flags (--scan-only, --plan, --doctor, --validate-target, defaults, and so on). Deep tables and more links are in references/differences.md.

Files18
18 files · 124.2 KB

Select a file to preview

Overall Score

82/100

Grade

B

Good

Safety

80

Quality

85

Clarity

83

Completeness

78

Summary

This skill guides an AI agent through migrating Claude Code configuration, skills, instructions, subagents, and MCP settings into Codex format. It orchestrates a Python migrator tool with CLI flags (--scan-only, --plan, --doctor, --validate-target) and implements a self-healing loop: scan → dry-run → execute → validate → fix → re-run until complete. The skill emphasizes autonomy (do not ask for confirmation), precise artifact manipulation (generate Codex files, preserve unrelated config, delete orphans with --replace), and clear reporting in tabular format with status columns (Added, Check before using, Not Added).

Detected Capabilities

file readfile writedirectory traversalshell command executionPython script invocationYAML/TOML/JSON parsingconfiguration generationsymlink creationfile copying

Trigger Keywords

Phrases that MCP clients use to match this skill to user intent.

migrate to codexclaude code migrationconvert skills to codexcodex config setupport subagentsrewrite hooks

Risk Signals

INFO

File write to project-scoped and user-scoped Codex directories (.codex/, .agents/, ~/.codex/)

cli.py: write_artifact(), write_migration_report()
WARNING

Automatic deletion of orphaned Codex artifacts with --replace flag

cli.py: deploy_tree(), DeploymentPlan
INFO

Symlink creation from source Claude files to target AGENTS.md

cli.py: symlink_target(), convert_instructions()
INFO

File reading from Claude Code configuration surfaces (.claude/, .mcp.json, .claude.json)

migrate/settings.py, migrate/mcps.py, migrate/hooks.py
WARNING

Python subprocess execution via migrator CLI invocation

SKILL.md: $MIGRATE_TO_CODEX command pattern
INFO

Broad directory traversal with rglob() across source and target trees

cli.py: deploy_tree(), migrate/skills.py: skill_support_artifacts()

Referenced Domains

External domains referenced in skill content, detected by static analysis.

code.claude.comdevelopers.openai.comdocs.claude.comwww.apache.org

Use Cases

  • Migrate Claude Code workflow to Codex
  • Convert Claude skills and commands to Codex skills
  • Port Claude subagents to Codex custom agents
  • Translate Claude MCP config to Codex config.toml
  • Rewrite Claude hooks into Codex hooks.json
  • Generate Codex AGENTS.md from Claude instructions

Quality Notes

  • Excellent scope boundaries: only modifies .codex/, .agents/, and ~/.codex/ directories when target is selected; explicitly guards against editing source Claude files, secrets, or unrelated projects
  • Clear autonomy model: agent is instructed not to ask for confirmation once a target is selected, reducing friction in loops
  • Comprehensive error handling: --plan, --doctor, and --validate-target flags provide non-destructive inspection before real writes
  • Self-healing loop guidance is well-structured and repeatable: scan → dry-run → execute → validate → fix → repeat
  • Migration report format is precise: status column (Added/Check before using/Not Added) with notes explaining what changed and why
  • Detailed differences.md reference with mappings between Claude and Codex semantics (e.g., allowed-tools → prompt guidance, skills → developer_instructions)
  • Field mappings are partial and documented: model names, permission modes, MCP headers/env vars include caveats and fallback guidance
  • Python codebase is modular and maintainable: separate modules for each migration surface (skills.py, agents.py, hooks.py, mcps.py) with clear responsibility boundaries
  • Validation logic covers TOML parseability, skill frontmatter presence, custom-agent required fields, AGENTS.md file size thresholds
  • Manual migration blocks are auto-generated in output files to flag unsupported semantics for human review
Model: claude-haiku-4-5-20251001Analyzed: Jun 4, 2026

Reviews

Add this skill to your library to leave a review.

No reviews yet

Be the first to share your experience.

Version History

v1.1

Content updated

2026-06-04

Latest
v1.0

No changelog

2026-04-27

Add openai/migrate-to-codex to your library

Command Palette

Search for a command to run...