Use Codex with Xiaomi MiMo through MuxLayer

When to use this

Use this guide if you want:

Codex to call Xiaomi MiMo models while keeping a one-click path back to the official config.
Codex web_search_preview requests translated to MiMo web_search when the selected MiMo model supports it.
MiMo reasoning content preserved across multi-turn coding conversations.
Automatic handling for MiMo Open API keys and Token Plan keys.
One local gateway that can switch Codex between MiMo, DeepSeek, OpenAI, Kimi, GLM, DashScope, or another provider.

Quick Setup

Download MuxLayer from Releases and open the app.
Go to Quick Setup or Providers.
Add a Xiaomi MiMo provider and paste your MiMo API key.
Let MuxLayer detect the key type and fill the base URL, protocol endpoints, default model, and capability matrix.
Start the gateway from Overview or Gateway. The default client endpoint is http://127.0.0.1:9090.
Open Clients and click Apply Config on the Codex card.
Send a test message in Codex.

MuxLayer keeps the official Codex configuration restorable, so you can switch back from the Codex card when needed.

What MuxLayer configures

Codex side	MuxLayer side	MiMo side
OpenAI Responses API	`/v1/responses` local gateway route	MiMo Chat or Anthropic-compatible endpoint
Codex model names	Model Mapping or `agentgate` virtual model	MiMo model IDs such as `mimo-v2.5-pro`, `mimo-v2.5`, or `mimo-v2-flash`
Codex reasoning/tool flow	Protocol conversion and request tracing	MiMo `reasoning_content`, model capability matrix, and web search handling

Chinese Notes / 中文说明

如果你搜索的是“Codex 使用小米 MiMo”“Codex 接入 MiMo”“mimo2codex 替代方案”，MuxLayer 的定位不是单个 MiMo 代理，而是把 Codex 的官方模型入口变成本地可控入口：它可以连接 MiMo，也能在 MiMo、DeepSeek、OpenAI、Kimi、GLM、通义千问等 Provider 之间切换。

常见路径是：

Codex -> http://127.0.0.1:9090/v1/responses -> MuxLayer -> Xiaomi MiMo

MiMo 支持多种模型和 key 类型。MuxLayer 会按 MiMo Open API / Token Plan 的差异自动处理 host、模型能力、reasoning_content、web_search 降级和模型映射。

MiMo-specific behavior

Area	Behavior
Models	Supports MiMo chat models such as `mimo-v2.5-pro`, `mimo-v2-pro`, `mimo-v2.5`, `mimo-v2-omni`, and `mimo-v2-flash`.
Token Plan	Keeps Token Plan region hosts consistent for `cn`, `sgp`, and `ams`.
Reasoning	Preserves multi-turn `reasoning_content` where MiMo expects it.
Web search	Degrades gracefully when the paid MiMo Web Search Plugin is unavailable.
Vision	Uses the per-model capability matrix to promote image requests to a vision-capable sibling model when possible.

Troubleshooting

Symptom	Check
MiMo returns a host or auth error	Check whether the key is Open API `sk-` or Token Plan `tp-`, and verify the region host.
MiMo rejects `web_search`	Check whether the paid Web Search Plugin is enabled; MuxLayer can strip and retry in supported cases.
Image requests fail	Check the MiMo model capability matrix; not every MiMo model supports vision.
Gateway is unreachable	Make sure the MuxLayer gateway is running on `127.0.0.1:9090`; `1420` is only the development UI port.