codex-app-server
Installation
SKILL.md
Codex App Server
Use this skill when building around Codex App Server primitives. Keep the client/harness thin and deterministic.
Overview
Use this file for quick orientation and durable mental models only. For exact protocol fields, approvals, config keys, transport details, and other evolving behavior, prefer the local probe workflow for installed-build truth and use official docs via MCP (openaiDeveloperDocs) for the latest documented behavior.
What App Server Is
Codex App Server is the client-friendly JSON-RPC surface Codex uses to power rich clients such as IDE extensions and partner integrations.
- It hosts Codex threads as durable runtime sessions behind a bidirectional protocol.
- It turns lower-level harness activity into UI-ready thread, turn, item, delta, and approval events.
- It lets clients reuse the same Codex harness across different surfaces without re-implementing the agent loop.
- It is the first-class integration surface when you need authentication, conversation history, approvals, streamed agent events, skills, apps/connectors, MCP status, or config/auth flows.
- If the task is one-shot automation, batch work, or CI, prefer the Codex SDK instead of App Server.