app-server.md Codex Docs, 2026-05-02 00:48 UTC → 2026-05-05 23:00 UTC

3Codex app-server is the interface Codex uses to power rich clients (for example, the Codex VS Code extension). Use it when you want a deep integration inside your own product: authentication, conversation history, approvals, and streamed agent events. The app-server implementation is open source in the Codex GitHub repository ([openai/codex/codex-rs/app-server](https://github.com/openai/codex/tree/main/codex-rs/app-server)). See the [Open Source](https://developers.openai.com/codex/open-source) page for the full list of open-source Codex components.3Codex app-server is the interface Codex uses to power rich clients (for example, the Codex VS Code extension). Use it when you want a deep integration inside your own product: authentication, conversation history, approvals, and streamed agent events. The app-server implementation is open source in the Codex GitHub repository ([openai/codex/codex-rs/app-server](https://github.com/openai/codex/tree/main/codex-rs/app-server)). See the [Open Source](https://developers.openai.com/codex/open-source) page for the full list of open-source Codex components.

4 4 

5If you are automating jobs or running Codex in CI, use the5If you are automating jobs or running Codex in CI, use the

6[Codex SDK](https://developers.openai.com/codex/sdk) instead.6 <a href="/codex/sdk">Codex SDK</a> instead.

7 7 

8## Protocol8## Protocol

9 9 

75Example (Node.js / TypeScript):75Example (Node.js / TypeScript):

76 76 

77```ts77```ts

78import { spawn } from "node:child_process";78 

79import readline from "node:readline";79 

80 80 

81const proc = spawn("codex", ["app-server"], {81const proc = spawn("codex", ["app-server"], {

82 stdio: ["pipe", "pipe", "inherit"],82 stdio: ["pipe", "pipe", "inherit"],