> ## Documentation Index
> Fetch the complete documentation index at: https://arize-ax.mintlify.dev/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# GitHub Copilot

> Trace GitHub Copilot sessions in VS Code and the Copilot CLI in Arize AX using the Arize Coding Harness Tracing.

> Trace GitHub Copilot sessions in VS Code and the Copilot CLI in Arize AX for full observability.

[GitHub Copilot](https://github.com/features/copilot) is GitHub's AI pair programmer for VS Code and the command line. The [Arize Coding Harness Tracing](https://github.com/Arize-ai/coding-harness-tracing) instruments both Copilot surfaces and exports [OpenInference](https://github.com/Arize-ai/openinference) spans to Arize AX or Phoenix. VS Code uses per-event hook files; the CLI uses a single `hooks.json`.

## Launch Arize AX

To get started, sign up for a free [Arize AX account](https://app.arize.com/auth/join) and get your Space ID and API Key:

1. Log in at [app.arize.com](https://app.arize.com)
2. Click **Settings** and copy the **Space ID**
3. Open the **API Keys** tab and create or copy an API key

## Install

Copilot hooks are installed at the **project level** under `.github/hooks/`. Run the installer from the root of each repository where you want tracing.

### Curl installer

**macOS / Linux:**

```bash theme={null}
cd /path/to/your/project
curl -sSL https://raw.githubusercontent.com/Arize-ai/coding-harness-tracing/main/install.sh | bash -s -- copilot
```

**Windows (PowerShell):**

```powershell theme={null}
cd C:\path\to\your\project
iwr -useb https://raw.githubusercontent.com/Arize-ai/coding-harness-tracing/main/install.bat -OutFile $env:TEMP\install.bat
& $env:TEMP\install.bat copilot
```

### Local clone

```bash theme={null}
git clone https://github.com/Arize-ai/coding-harness-tracing.git
cd /path/to/your/project
/path/to/coding-harness-tracing/install.sh copilot         # macOS / Linux
\path\to\coding-harness-tracing\install.bat copilot        # Windows
```

The installer prompts for your backend (Phoenix or Arize AX) and project name, writes credentials to `~/.arize/harness/config.yaml`, and registers VS Code (`.github/hooks/*.json`) and Copilot CLI (`.github/hooks/hooks.json`) hooks in the current project.

## Configuration

Credentials live in `~/.arize/harness/config.yaml` and apply across all projects. Per-project environment variables override `config.yaml` and can be set in your shell profile.

### Phoenix (self-hosted)

```bash theme={null}
export PHOENIX_ENDPOINT="http://localhost:6006"
export ARIZE_PROJECT_NAME="copilot"
export ARIZE_TRACE_ENABLED="true"
```

### Arize AX (cloud)

```bash theme={null}
export ARIZE_API_KEY="<your-api-key>"
export ARIZE_SPACE_ID="<your-space-id>"
export ARIZE_PROJECT_NAME="copilot"
export ARIZE_TRACE_ENABLED="true"
```

### Redaction controls

Each `ARIZE_LOG_*` flag accepts `"true"` or `"false"` and defaults to `"true"`. Set to `"false"` to opt out per category:

```bash theme={null}
export ARIZE_LOG_PROMPTS="false"
export ARIZE_LOG_TOOL_DETAILS="false"
export ARIZE_LOG_TOOL_CONTENT="false"
```

| Flag                     | Redacts                                 |
| :----------------------- | :-------------------------------------- |
| `ARIZE_LOG_PROMPTS`      | User prompt and assistant response text |
| `ARIZE_LOG_TOOL_DETAILS` | Tool names and arguments                |
| `ARIZE_LOG_TOOL_CONTENT` | Tool call output content                |

## Observe

Once tracing is enabled, Copilot activity from both VS Code and the CLI streams to Arize AX. You'll see:

* **Turn traces** — each prompt → response cycle as a parent span
* **Tool spans** — nested spans for each tool call with inputs, outputs, and duration
* **Subagent spans** — activity from any subagents Copilot spawns (VS Code)
* **Error spans** — `errorOccurred` events from the CLI
* **Session grouping** — all turns from the same session grouped by `session_id`

### Hooks Captured

Copilot in VS Code and on the CLI use different event names. The Agent Kit handles both with one install command.

| Surface | Hook File                          | Events                                                                                            |
| :------ | :--------------------------------- | :------------------------------------------------------------------------------------------------ |
| VS Code | `.github/hooks/session-start.json` | `SessionStart`                                                                                    |
| VS Code | `.github/hooks/user-prompt.json`   | `UserPromptSubmit`                                                                                |
| VS Code | `.github/hooks/pre-tool.json`      | `PreToolUse`                                                                                      |
| VS Code | `.github/hooks/post-tool.json`     | `PostToolUse`                                                                                     |
| VS Code | `.github/hooks/stop.json`          | `Stop`                                                                                            |
| VS Code | `.github/hooks/subagent-stop.json` | `SubagentStop`                                                                                    |
| CLI     | `.github/hooks/hooks.json`         | `sessionStart`, `userPromptSubmitted`, `preToolUse`, `postToolUse`, `errorOccurred`, `sessionEnd` |

## Reference

For the full list of environment variables, default file paths, and troubleshooting steps, see the [Copilot tracing README](https://github.com/Arize-ai/coding-harness-tracing/blob/main/tracing/copilot/README.md).

## Uninstall

Run from the project root where you installed the hooks:

```bash theme={null}
curl -sSL https://raw.githubusercontent.com/Arize-ai/coding-harness-tracing/main/install.sh | bash -s -- uninstall copilot
```

## Resources

<CardGroup>
  <Card icon="github" href="https://github.com/Arize-ai/coding-harness-tracing" title="Arize Coding Harness Tracing" horizontal />

  <Card icon="github" href="https://github.com/Arize-ai/openinference" title="OpenInference" horizontal />

  <Card icon="book-open" href="https://github.com/features/copilot" title="GitHub Copilot" horizontal />
</CardGroup>