Sider

A popular AI sidebar for your browser that can run on your own OpenAI-compatible API key.

What Sider is

Sider is a popular AI assistant that lives in a browser sidebar on Chrome and Edge, used for chatting, summarizing and writing on any web page. Its Custom API Key mode lets you bring your own OpenAI-compatible endpoint, so its core chat, write and ask tools can run on TokenMix with Claude, GPT or DeepSeek.

Before you start

• Install Sider from the Chrome Web Store or Edge Add-ons.
• Sign up at tokenmix.ai, open the Console, go to API Keys, and create a key that starts with sk-tm-.

Connect TokenMix

1. Open Sider's settings and go to General, then AI Access, then Service Provider.
2. Switch to "Custom API Key".
3. Choose "OpenAI" as the provider, then click Settings.
4. Base URL: enter https://api.tokenmix.ai/v1 and keep the /v1.
5. API Key: paste your sk-tm- key.
6. Click "Check". When "Connection successful" appears, you are done. Then pick a model from Sider's model list.

Check it works

Open the Sider sidebar, select a model, and send a short message such as "hello". A reply confirms it is using TokenMix. You can see the spend in the TokenMix Console.

Common questions

Some features still use Sider's own service: core chat, write, ask and context-menu tools run on your custom key, but a few extras such as YouTube summaries and some translation features stay on Sider's own backend and do not go through TokenMix.

Connection check fails: confirm the Base URL is https://api.tokenmix.ai/v1 with the /v1, and that your sk-tm- key is active in the TokenMix Console.

Which models to pick: for general use, Claude Sonnet 4.6, GPT-5.4 and DeepSeek V4 Pro are good starting points.