Coding Workspace Codex Harness Template

Minimal template for a repo-cloning coding workspace that runs Codex via the Codex CLI.

Note

The SDK + MCP server path does not currently support the latest Codex models (including codex-5.3-pro), so this template uses Codex CLI instead.

• Use baked codex/config.toml (/app/codex/config.toml) as the source of truth for Codex runtime settings.

What this template does

• Clones the target repository into /workspace.
• Optionally boots GitHub CLI auth when a token is provided.
• Supports optional git_author_email task param for commit author/committer email.
• Uses baked Codex config at /app/codex/config.toml.
• Points Codex CLI to /app/codex/config.toml via CODEX_HOME=/app/codex.
• Runs codex exec and codex exec resume (JSON mode) to preserve thread state across task events.

Runtime

• sdk_type: codex_agent_sdk
• Codex CLI (@openai/codex) preinstalled
• git, gh, node, and npm available in the container

OpenAI Docs

• Multi-agent (Codex CLI): https://developers.openai.com/codex/multi-agent
• MCP with Codex CLI: https://developers.openai.com/codex/mcp
• AGENTS.md guide: https://developers.openai.com/codex/guides/agents-md
• Config basics: https://developers.openai.com/codex/config-basic
• Config advanced: https://developers.openai.com/codex/config-advanced
• Config reference: https://developers.openai.com/codex/config-reference/
• Config sample: https://developers.openai.com/codex/config-sample
• Agents SDK guide (background/reference): https://developers.openai.com/codex/guides/agents-sdk/

Codex Config

• Source in image: codex/config.toml (from repo path codex/config.toml)
• Runtime path: /app/codex/config.toml