---
url: https://docs.freetheai.org/guides/github-copilot.md
description: >-
  Use free FreeTheAI models in VS Code chat and Copilot agent mode with bring
  your own key: the Custom Endpoint provider and chatLanguageModels.json.
---

# VS Code Copilot Chat

VS Code chat adds FreeTheAI through its Custom Endpoint provider (bring your own key). It works even without a Copilot plan.

Category: [Coding tools](/guides/#coding-tools). Before you start, you need a FreeTheAI account, an API key, and today's [check-in](/getting-started/check-in).

## Settings

| Setting | Value |
| --- | --- |
| Provider | `Custom Endpoint` |
| API type | `Chat Completions` |
| url | `https://api.freetheai.org/v1/chat/completions` |
| API key | Your FreeTheAI key (`ftai_...`, 53 characters) |

## Steps

### Open the language models

In the chat model picker, press the gear (Manage Language Models), or run Chat: Manage Language Models.

### Add a Custom Endpoint

Press Add Models, choose Custom Endpoint, enter a group name (FreeTheAI) and your key, and choose Chat Completions.

### Describe the models

VS Code opens `chatLanguageModels.json`. Fill in the models and save:

```json
[
  {
    "name": "FreeTheAI",
    "vendor": "customendpoint",
    "apiKey": "ftai_your_key_here",
    "apiType": "chat-completions",
    "models": [
      {
        "id": "fta/zai/glm-5.3",
        "name": "GLM 5.3",
        "url": "https://api.freetheai.org/v1/chat/completions",
        "toolCalling": true,
        "vision": false,
        "maxInputTokens": 200000,
        "maxOutputTokens": 32000
      }
    ]
  }
]
```

### Pick the model

Choose GLM 5.3 in the chat model picker. Restart VS Code if it does not show up.

## Tips

* If VS Code already wrote an apiKey value (a reference to its secret storage), keep that line instead of pasting your key.
* Without a GitHub sign-in, set chat.utilityModel and chat.utilitySmallModel to a FreeTheAI model so titles and commit messages work.
* Bring your own key covers chat and agent mode, not inline code completions.

## Common questions

### I used the old "OpenAI Compatible" provider. Does it still work?

It is deprecated. Add FreeTheAI again with the Custom Endpoint provider and the chat-completions API type.

### Why do I get a 401 "invalid API key" error?

The key is wrong or incomplete. Remove the FreeTheAI group, add it again, and paste the whole ftai\_ key (53 characters).

### The model does not show in the picker. What now?

Save `chatLanguageModels.json` and restart VS Code.

### Agent mode does nothing with FreeTheAI. Why?

Keep "toolCalling": true and use a model that supports tools, such as `fta/zai/glm-5.3` or `fta/kimi/k3`.

### Why do I get a 403 error?

Free models need one check-in a day. Check in at [freetheai.org/checkin](https://freetheai.org/checkin), then try again.

## More help

* [Every API error and its fix](/errors)
* [Limits and the daily reset](/concepts/limits)
* [VS Code Copilot Chat website](https://code.visualstudio.com/docs/agent-customization/language-models)

::: info How this guide was checked
Checked against the VS Code language models docs (Custom Endpoint provider) on 2026-09-29.
:::