Pull every string value out of the current file in one keystroke
JSON, YAML, CSV, TOML, INI, and Environment files
Useful? A star or rating is how other developers find it —
★ GitHub ·
★ Marketplace ·
★ Open VSX
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 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 — 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 on npm and as io.github.nolindnaidoo/string-le in the MCP registry.
Configuring it by hand — any host with an MCP config file
Most hosts read a JSON config. Add one entry:
{
"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:
npm install -g string-le-mcp
{
"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:
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.
| 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
bun install
bun run build
bun run typecheck
bun run test
bun run test:integration
bun run lint
bun run package
Architecture and conventions live in AGENTS.md. Changes are tracked in CHANGELOG.md.
| 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.
Testing
| 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-to-end test that installs the
built .vsix into a clean profile.
Generated from coverage/coverage-summary.json by
scripts/coverage-readme.js; CI fails if this section drifts from a fresh
run. Reproduce with bun run test:coverage.
More from the LE Family
Every tool in the family, one page: letools.dev
All ten also ship as MCP servers — npx <name>-mcp gives any agent the same engine.
- Paths-LE - Extract file paths from JS/TS imports, JSON, HTML, CSS, TOML, CSV, and .env
- Numbers-LE - Extract numeric values from JSON, YAML, CSV, TOML, INI, and .env
- EnvSync-LE - Spot missing keys across your .env files, with a markdown report
- Regex-LE - Find, test, and validate regular expressions with ReDoS screening
- Secrets-LE - Detect and sanitize credentials locally, before you commit
- Scrape-LE - Check whether a page is scrapeable before you write the scraper
- Colors-LE - Extract and analyze colors from CSS, SCSS, LESS, Stylus, HTML, JS/TS, and SVG
- URLs-LE - Extract URLs from documentation, configs, and code
- Dates-LE - Extract and analyze dates from logs, configs, and code
Also by nolindnaidoo
Rust
Contact Developer — GitHub · LinkedIn
License
MIT © nolindnaidoo