string-le

<p align="center">
  <img src="src/assets/images/icon.png" alt="Strings-LE Logo" width="96" height="96"/>
</p>
<h1 align="center">Strings-LE: Zero Hassle String Extraction</h1>
<p align="center">
  <b>Pull every string value out of the current file in one keystroke</b><br/>
  <i>JSON, YAML, CSV, TOML, INI, and Environment files</i>
</p>

<p align="center">
  <a href="https://marketplace.visualstudio.com/items?itemName=nolindnaidoo.string-le">
    <img src="https://img.shields.io/badge/Install%20from-VS%20Code-blue?style=for-the-badge&logo=visualstudiocode" alt="Install from VS Code Marketplace" />
  </a>
  <a href="https://open-vsx.org/extension/OffensiveEdge/string-le">
    <img src="https://img.shields.io/open-vsx/dt/OffensiveEdge/string-le?style=for-the-badge&label=Open%20VSX&color=blue" alt="Open VSX downloads" />
  </a>
  <a href="https://www.npmjs.com/package/string-le-mcp">
    <img src="https://img.shields.io/npm/v/string-le-mcp?style=for-the-badge&label=MCP%20server&color=blue&logo=npm" alt="string-le-mcp on npm" />
  </a>
  <a href="https://letools.dev">
    <img src="https://img.shields.io/badge/LE%20Tools-letools.dev-blue?style=for-the-badge" alt="LE Tools" />
  </a>
</p>

---

<p align="center">
  <img src="src/assets/images/demo.gif" alt="String-LE Demo" style="max-width: 100%; height: auto;" />
</p>

> **Useful?** A star or rating is how other developers find it —
> [★ GitHub](https://github.com/nolindnaidoo/string-le) ·
> [★ Marketplace](https://marketplace.visualstudio.com/items?itemName=nolindnaidoo.string-le&ssr=false#review-details) ·
> [★ Open VSX](https://open-vsx.org/extension/OffensiveEdge/string-le/reviews)

## What it does

Open a file, press `Ctrl+Alt+E` (`Cmd+Alt+E` on Mac), and every string value in the document lands in a new editor — deduplicate and sort it from there. Works in VS Code and in VS Code–based editors like Cursor and VSCodium (installable from Open VSX).

- **i18n prep** — flatten locale files (JSON/YAML) into a clean list of translatable values
- **Config review** — see every string value in a TOML/INI/.env file at a glance
- **CSV mining** — pull one column, several, or all of them; stream very large files

## Use it from an AI agent

The same engine runs as an [MCP](https://modelcontextprotocol.io) server, so an agent can call it directly instead of you running a command.

| Editor | How |
|---|---|
| **VS Code** 1.101+ | Nothing to install — the extension registers `extract_strings` with agent mode |
| **Zed** | [String-LE](https://github.com/zed-industries/extensions/pull/7082) — *pending review* |
| **Claude Code** | `claude mcp add string-le -- npx -y string-le-mcp` |
| **Cursor, Windsurf, anything else** | point it at `npx string-le-mcp` |

```
extract_strings(content, format?, filename?, dedupe?, maxResults?)
```

Returns the values in document order, capped at 500 by default with `meta.truncated`. A format is optional — any unrecognised format falls back to quoted strings.

The server takes content and returns data — it reads no files and makes no network requests of its own. Published as [`string-le-mcp`](https://www.npmjs.com/package/string-le-mcp) on npm and as `io.github.nolindnaidoo/string-le` in the [MCP registry](https://registry.modelcontextprotocol.io).

<details>
<summary><b>Configuring it by hand</b> — any host with an MCP config file</summary>

Most hosts read a JSON config. Add one entry:

```json
{
  "mcpServers": {
    "string-le": {
      "command": "npx",
      "args": ["-y", "string-le-mcp"]
    }
  }
}
```

`-y` skips the install prompt on first run. Pin a version if you would rather not track releases — `string-le-mcp@2.2.1`.

Prefer not to go through `npx` on every launch? Install it once and point at the binary instead:

```bash
npm install -g string-le-mcp
```

```json
{
  "mcpServers": {
    "string-le": { "command": "string-le-mcp" }
  }
}
```

It speaks MCP over stdio and needs no environment variables, no API key and no configuration of its own. To check it before wiring it into anything:

```bash
echo '{"jsonrpc":"2.0","id":1,"method":"tools/list"}' | npx -y string-le-mcp
```

That prints the tool list and exits — if you see `extract_strings`, the server works.

</details>

## Supported formats

| Format | Language IDs | What gets extracted |
|---|---|---|
| JSON | `json` | String values (parsed; keys, numbers, and booleans excluded) |
| YAML | `yaml` | String values including unquoted plain scalars, block/folded scalars, and multi-document files |
| CSV | `csv` | Cells, with optional header handling, column selection, and a streaming mode for large files |
| TOML | `toml` | String values including multiline strings; dates and numbers are excluded as typed values |
| INI | `ini` | Values (INI is untyped, so numeric-looking values are extracted as strings) |
| Environment | `dotenv`, `env` | Values (`export` prefixes, quotes, and inline comments handled) |
| Anything else | — | Fallback scan for `"double"`, `'single'`, or `` `backtick` `` quoted strings on a single line |

Values are trimmed; empty values are dropped; keys are never extracted. The fallback scan cannot see unquoted or multi-line strings — that is why the six formats above get real parsers. Parse errors are silent unless `string-le.showParseErrors` is on.

## Commands

| Command | Description |
|---|---|
| `String-LE: Extract Strings` (`Ctrl+Alt+E` / `Cmd+Alt+E`) | Extract all string values from the active document |
| `String-LE: Deduplicate Strings` | Remove duplicate lines from the active document |
| `String-LE: Sort Strings` | Sort lines alphabetically or by length |
| `String-LE: Toggle CSV Streaming` | Enable/disable streaming for large CSV files |
| `String-LE: Open Settings` | Open String-LE settings |
| `String-LE: Help & Troubleshooting` | Built-in documentation |

## Settings

| Setting | Default | Description |
|---|---|---|
| `string-le.openResultsSideBySide` | `true` | Open results beside the current editor |
| `string-le.postProcess.openInNewFile` | `true` | Post-process commands write to a new file instead of editing in place |
| `string-le.copyToClipboardEnabled` | `false` | Also copy results to the clipboard (disabled for CSV output) |
| `string-le.dedupeEnabled` | `false` | Deduplicate results automatically after extraction |
| `string-le.sortEnabled` | `false` | Sort results automatically after extraction |
| `string-le.sortMode` | `off` | `alpha-asc`, `alpha-desc`, `length-asc`, `length-desc` |
| `string-le.csv.streamingEnabled` | `false` | Stream CSV results into the editor incrementally |
| `string-le.showParseErrors` | `false` | Show parse errors as notifications |
| `string-le.notificationsLevel` | `silent` | `all` = every notification, `important` = warnings + errors, `silent` = errors only |
| `string-le.safety.enabled` | `true` | Guardrails for very large files/outputs |
| `string-le.safety.fileSizeWarnBytes` | `1000000` | Warn before extracting above this file size |
| `string-le.safety.largeOutputLinesThreshold` | `50000` | Offer Open/Copy/Cancel above this result count |
| `string-le.safety.manyDocumentsThreshold` | `8` | Confirm before opening this many result documents (CSV multi-column) |
| `string-le.statusBar.enabled` | `true` | Show the status bar item |
| `string-le.telemetryEnabled` | `false` | Local-only event log (see Privacy) |

## Languages

Twelve languages besides English:

German · Spanish · French · Indonesian · Italian · Japanese · Korean ·
Portuguese (Brazil) · Russian · Ukrainian · Vietnamese · Chinese (Simplified)

Both halves are covered — the manifest (command titles, setting names and
descriptions) and everything shown while the extension runs (notifications,
the status bar, quick-picks and prompts). The extension follows VS Code's
display language, so it matches whatever the editor is already set to; no
setting of its own.

## Privacy & security

- **No network access.** The extension never sends data anywhere. The `telemetryEnabled` setting only writes events to a local Output Channel you can inspect (`String-LE`).
- **The MCP server holds the same line.** It takes content as an argument and returns data: no filesystem access, no network calls, no telemetry. Your agent already has file-read tools, so duplicating them inside the server would add a path-traversal surface for no capability. `check:mcp-bundle` fails the build if the server ever imports something that could reach either.
- Error notifications redact home directories and credential-shaped fragments.

## Development

```bash
bun install
bun run build            # esbuild bundle -> dist/extension.js
bun run typecheck        # tsc --noEmit (includes tests)
bun run test             # vitest unit suite
bun run test:integration # real VS Code extension host
bun run lint             # biome
bun run package          # VSIX into release/
```

Architecture and conventions live in [AGENTS.md](AGENTS.md). Changes are tracked in [CHANGELOG.md](CHANGELOG.md).

## Performance

<!-- performance:start -->
| Input | Size | Found | Time | Rate | Scan speed |
| --- | --- | --- | --- | --- | --- |
| JSON locale file | 1.77 MB | 40,000 | 9.53 ms | 4,198,116/sec | 185.9 MB/s |
| YAML locale file | 1.01 MB | 30,000 | 13.33 ms | 2,250,169/sec | 75.7 MB/s |
| CSV strings | 1.35 MB | 80,002 | 28.29 ms | 2,827,438/sec | 47.8 MB/s |

Median of 7 runs after warmup, on Apple M5 Pro, 24 GB RAM, Node 24.3.0. Inputs are generated
by `scripts/benchmark.ts` rather than checked in, so the sizes above are
exactly what was measured. Reproduce with `bun run benchmark`.

These are machine-specific and are not asserted in CI — a benchmark that gates
a build only tells you how busy the runner was.
<!-- performance:end -->

## Testing

<!-- coverage:start -->
| Metric | Coverage |
| --- | --- |
| Statements | 88.69% |
| Branches | 78.30% |
| Functions | 96.55% |
| Lines | 90.08% |

250 test cases across 22 files, plus an integration suite that runs
in a real VS Code extension host and an end