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Genesis Genesis

Codex

Codex is OpenAI’s coding agent (CLI and cloud). Genesis runs as a skill bundle under ~/.codex/skills/; personas are declared via AGENTS.md files.

File paths

Section titled “File paths”
PrimitivePath
Module Entrypoint (skill folder)~/.codex/skills/<skill-name>/SKILL.md
Persona Scoping FileAGENTS.md (project root or nested)
Scope-Attached Rule FileAGENTS.md sections (path-scoped by directory)

How /genesis resolves

Section titled “How /genesis resolves”

After npx skills add danielmeppiel/genesis, the loader writes Genesis to ~/.codex/skills/genesis/. In a Codex session, type:

/genesis <what you want designed>

The dispatcher matches the slash command against the user-level skill folder.

AGENTS.md — the universal persona format

Section titled “AGENTS.md — the universal persona format”

Codex follows the cross-vendor AGENTS.md convention: a markdown file at the project root that scopes the agent’s voice, expertise, and constraints. Nested AGENTS.md files cascade for sub-trees, providing path-scoped behavior without a separate rule-file primitive.

AGENTS.md
You are reviewing a PR. Your lens is missing-test coverage.
Hard constraint: never approve, never auto-merge.

This single-file approach is the Codex concession. In Genesis terms, an AGENTS.md file simultaneously realizes PERSONA SCOPING FILE and SCOPE-ATTACHED RULE FILE — the harness does not separate them, but the design layer should.

Tool surface

Section titled “Tool surface”

Codex CLI preloads shell command execution and file / search tools. The cloud-hosted variant additionally exposes a sandboxed network and code-execution surface. MCP support is documented at the link below.

Official documentation

Section titled “Official documentation”
  • OpenAI Codex (developers.openai.com/codex) — canonical authority for the Codex CLI and cloud surface. (Verified 200 OK.)
  • Note: the older platform.openai.com/docs/codex returned 403 on automated HEAD requests during URL verification; developers.openai.com/codex/ is the current canonical landing page and resolves cleanly.

See also

Section titled “See also”