# How to Configure Understand Anything: JSON Settings and CLI Flags

> Learn how to configure Understand Anything using JSON settings and CLI flags. Master your setup with our guide.

- Repository: [Yuxiang Lin/Understand-Anything](https://github.com/Lum1104/Understand-Anything)
- Tags: how-to-guide
- Published: 2026-06-05

---

**You configure Understand Anything through a JSON file at [`.understand-anything/config.json`](https://github.com/Lum1104/Understand-Anything/blob/main/.understand-anything/config.json) that is automatically created on first run and updated via CLI flags like `--language` and `--auto-update`.**

Understand Anything is a multi-agent plugin that builds a knowledge graph of your codebase. Configuration persistence is handled through a central JSON file controlled by command-line flags defined in [`understand-anything-plugin/skills/understand/SKILL.md`](https://github.com/Lum1104/Understand-Anything/blob/main/understand-anything-plugin/skills/understand/SKILL.md). This guide covers the core options, lifecycle, and programmatic interfaces for managing these settings.

## Configuration File Location and Structure

The plugin stores all persistent settings in [`.understand-anything/config.json`](https://github.com/Lum1104/Understand-Anything/blob/main/.understand-anything/config.json) at your project root. This file uses a simple key-value map structure that the persistence module reads and writes generically, allowing future extensions without core code changes.

### Core Configuration Options

The configuration file controls two primary behavioral settings:

**`autoUpdate`** — A boolean flag that determines whether the post-commit hook automatically rebuilds the knowledge graph after each git commit. When `true`, the hook defined in [`hooks/hooks.json`](https://github.com/Lum1104/Understand-Anything/blob/main/hooks/hooks.json) triggers incremental updates.

**`outputLanguage`** — An ISO-639-1 language code (e.g., `en`, `zh`, `ja`). This controls the language for all generated summaries, tags, tours, and UI labels throughout the analysis.

## Configuration Lifecycle

The configuration progresses through four distinct phases during plugin usage.

### First Run Initialization

When no configuration exists, the skill parses any `--language` flag provided. If omitted, it attempts to infer your system language, prompts for confirmation once, and then persists the result. The default state writes `autoUpdate: false` and `outputLanguage: "en"` (or your detected language) to the config file.

### Modifying Language Settings

Supplying `--language <code>` during execution overrides the stored value and immediately rewrites [`config.json`](https://github.com/Lum1104/Understand-Anything/blob/main/config.json). This persists your choice for all future analyses without requiring the flag again.

### Toggling Auto-Update

Using `--auto-update` writes `autoUpdate: true` to the configuration, while `--no-auto-update` sets it to `false`. These flags update the stored boolean directly in the JSON file.

### Incremental Execution

All subsequent plugin runs read [`.understand-anything/config.json`](https://github.com/Lum1104/Understand-Anything/blob/main/.understand-anything/config.json) to determine execution strategy. The persistence module checks these values to decide whether to rebuild the entire graph, perform an incremental update, or skip generation entirely.

## Implementation Details

The core package implements configuration management through specific modules in `understand-anything-plugin/packages/core/src/`.

### Persistence Module

In [`packages/core/src/persistence/index.ts`](https://github.com/Lum1104/Understand-Anything/blob/main/packages/core/src/persistence/index.ts), the `loadConfig` function handles file I/O operations:

```typescript
const CONFIG_FILE = "config.json";
export async function loadConfig(projectRoot: string): Promise<ProjectConfig> {
  // Reads and returns configuration from .understand-anything/config.json
}

```

This module loads the configuration at startup and provides the generic read/write capabilities that support the simple map structure.

### Type Definitions

The `ProjectConfig` interface is defined in [`packages/core/src/types.ts`](https://github.com/Lum1104/Understand-Anything/blob/main/packages/core/src/types.ts) (lines 118-120):

```typescript
interface ProjectConfig {
  autoUpdate: boolean;
  outputLanguage: string;
}

```

This type matches the JSON structure persisted to disk.

## Practical Configuration Examples

### Changing Output Language

Generate all summaries and tags in Chinese by running:

```bash
/understand --language zh

```

The first non-English execution prompts for confirmation; your answer is saved in [`.understand-anything/config.json`](https://github.com/Lum1104/Understand-Anything/blob/main/.understand-anything/config.json) alongside the `autoUpdate` setting.

### Enabling Automatic Updates

Turn on the post-commit hook to automatically maintain your knowledge graph:

```bash
/understand --auto-update

```

This writes `{"autoUpdate": true}` to the configuration file. To disable automatic updates later:

```bash
/understand --no-auto-update

```

### Inspecting Configuration Directly

View current settings using standard shell commands:

```bash
cat .understand-anything/config.json

```

Example output:

```json
{
  "autoUpdate": true,
  "outputLanguage": "zh"
}

```

### Programmatic Access

Import the persistence module to read configuration values in TypeScript:

```typescript
import { loadConfig } from "@understand-anything/core/src/persistence";

async function readSettings(projectRoot: string) {
  const cfg = await loadConfig(projectRoot);
  console.log("Auto-update enabled:", cfg.autoUpdate);
  console.log("Output language:", cfg.outputLanguage);
}

```

The `loadConfig` function returns a `ProjectConfig` object containing the current `autoUpdate` and `outputLanguage` values.

## Summary

- Configuration is stored in [`.understand-anything/config.json`](https://github.com/Lum1104/Understand-Anything/blob/main/.understand-anything/config.json) at the project root.
- Two core options control behavior: `autoUpdate` (boolean) and `outputLanguage` (ISO-639-1 code).
- The file initializes automatically on first run with language detection and confirmation.
- Update settings via `--language`, `--auto-update`, and `--no-auto-update` CLI flags.
- The `loadConfig()` function in [`packages/core/src/persistence/index.ts`](https://github.com/Lum1104/Understand-Anything/blob/main/packages/core/src/persistence/index.ts) provides programmatic access.

## Frequently Asked Questions

### Where is the Understand Anything configuration file stored?

The configuration file is located at [`.understand-anything/config.json`](https://github.com/Lum1104/Understand-Anything/blob/main/.understand-anything/config.json) in your project root. According to the source code in [`packages/core/src/persistence/index.ts`](https://github.com/Lum1104/Understand-Anything/blob/main/packages/core/src/persistence/index.ts), the `loadConfig` function specifically reads from this path to initialize the `ProjectConfig` type.

### How do I permanently change the output language?

Run `/understand --language <code>` using an ISO-639-1 language code such as `zh` for Chinese or `ja` for Japanese. This updates the `outputLanguage` field in [`config.json`](https://github.com/Lum1104/Understand-Anything/blob/main/config.json) immediately and persists for all future analyses without requiring you to supply the flag again.

### What does enabling auto-update actually do?

When `autoUpdate` is set to `true` via `/understand --auto-update`, the git hook defined in [`hooks/hooks.json`](https://github.com/Lum1104/Understand-Anything/blob/main/hooks/hooks.json) monitors your repository. After each commit, it checks this flag and triggers an incremental update of the knowledge graph automatically, eliminating the need to manually run the `/understand` skill.

### Can I manually edit the configuration file?

Yes. Since [`packages/core/src/persistence/index.ts`](https://github.com/Lum1104/Understand-Anything/blob/main/packages/core/src/persistence/index.ts) reads the file generically as a simple map, you can manually edit [`.understand-anything/config.json`](https://github.com/Lum1104/Understand-Anything/blob/main/.understand-anything/config.json) to adjust values or add future-compatible keys. Changes take effect on the next plugin execution when `loadConfig` parses the updated file.