A prose linter and AI-slop detector. WSC finds AI tells — words, phrases, and sentence structures overrepresented in AI-generated text, each flag backed by a published corpus study. It also catches classic writing issues: weasel words, passive voice, duplicate words, long sentences, nominalizations, hedging, and filler adverbs. Available as a web editor, HTTP API, MCP server, CLI, and GitHub Action.
- Web Editor - Real-time highlighting with inline fix buttons for all 8 detectors
- HTTP API - POST text with optional config, retrieve structured JSON responses
- MCP Server (Remote) - Connect AI assistants via Streamable HTTP transport
- MCP Server (Local) - Stdio-based server via
wsc-mcpon npm - CLI - Check files from the command line via
wsc-lint - GitHub Action - Run checks in CI with
::warningannotations - Configurable - Customize detectors with
.wscrc.jsonfiles
WSC flags patterns that research on AI-generated text finds overrepresented, and cites a source for every flag. It does not, and cannot, prove authorship. Classifier-based detectors carry a documented false-accusation risk: a Stanford study found that seven of them misflagged 61% of essays written by non-native English speakers. WSC avoids that trap by design — every flag is a specific, explainable edit that improves the text no matter who, or what, wrote it.
| Detector | Items | Description |
|---|---|---|
| Weasel Words | 95 words/phrases | Vague terms like "very", "basically", "arguably", "numerous" |
| Passive Voice | 260 irregular verbs | Auxiliary verbs + past participles (regular -ed + irregular) |
| Duplicate Words | — | Adjacent repeated words across whitespace, case-insensitive |
| Long Sentences | threshold: 30 words | Sentences exceeding a configurable word count |
| Nominalizations | 245 word pairs | Nouns replaceable with verbs ("utilization" → "use") |
| Hedging | 100 phrases | Phrases that weaken assertions ("I think", "it seems") |
| Filler Adverbs | 139 words | Adverbs adding emphasis without substance ("totally", "utterly") |
| AI Tells | 98 words (+111 inflected forms) + 83 phrases + 12 structural patterns | Words, phrases, and sentence constructions overrepresented in AI-generated text (delve, rich tapestry, It's not just X — it's Y) |
Word lists sourced from Matt Might's shell scripts and expanded with additional entries. AI tells draw on published corpus studies: Kobak et al. 2025 (Science Advances), Juzek & Ward 2025 (COLING), Liang et al. 2024 (Stanford), and Reinhart et al. 2025 (PNAS). Wikipedia's editor-maintained Signs of AI writing catalogue and AI-detection vendor reports round out the sources.
Create a .wscrc.json to customize detectors. All tools (API, MCP, CLI) support it.
{
"$schema": "https://wsc.theserverless.dev/schema.json",
"detectors": {
"weaselWords": {
"enabled": true,
"add": ["synergy", "leverage"],
"remove": ["very"]
},
"longSentences": { "maxWords": 25 },
"adverbs": { "enabled": false }
}
}Every field is optional. Missing fields use defaults. JSON Schema provides autocompletion in VS Code.
Analyze text for writing style issues. Accepts optional config object.
curl -X POST https://wsc.theserverless.dev/api/check \
-H "Content-Type: application/json" \
-d '{"text":"The code was written very quickly."}'Response:
{
"summary": {
"total": 2,
"weaselWords": 1,
"passiveVoice": 1,
"duplicateWords": 0,
"longSentences": 0,
"nominalizations": 0,
"hedging": 0,
"adverbs": 0
},
"issues": {
"weaselWords": [{ "word": "very", "index": 21, "line": 1, "column": 22, "context": "..." }],
"passiveVoice": [{ "phrase": "was written", "index": 9, "line": 1, "column": 10, "context": "..." }],
"duplicateWords": [],
"longSentences": [],
"nominalizations": [],
"hedging": [],
"adverbs": []
},
"meta": { "characterCount": 34, "wordCount": 6, "sentenceCount": 1, "processingTimeMs": 2 }
}With config:
curl -X POST https://wsc.theserverless.dev/api/check \
-H "Content-Type: application/json" \
-d '{"text":"The code was written very quickly.", "config":{"detectors":{"weaselWords":{"enabled":false}}}}'Returns API documentation as JSON.
Returns the list of all 8 detectors with descriptions, configurability, and word counts.
Runs a smoke test with known text and returns {"status":"healthy"} or 503.
Limits: Max 100,000 characters per request. CORS enabled for all origins.
The Writing Style Checker is available as an MCP server, letting AI assistants check your writing directly.
| Tool | Description |
|---|---|
check_text |
Analyze text for all 8 writing style issues. Accepts optional config. |
fix_duplicates |
Remove duplicate adjacent words and return cleaned text |
list_word_lists |
Return info about all detector word lists |
check_file |
(Local only) Read a file from disk and analyze it. Auto-discovers .wscrc.json. |
Connect any MCP client to the hosted server - no installation required.
{
"mcpServers": {
"writing-style-checker": {
"type": "url",
"url": "https://wsc.theserverless.dev/mcp"
}
}
}Install via npm for local usage. Includes check_file for analyzing files on disk with auto-discovery of .wscrc.json.
npx wsc-mcpClaude Desktop / Claude Code config:
{
"mcpServers": {
"writing-style-checker": {
"command": "npx",
"args": ["wsc-mcp"]
}
}
}See the wsc-mcp npm page for full documentation.
Check files from the command line.
# Check all markdown files
npx wsc-lint check "**/*.md"
# Read from stdin
echo "The code was written very quickly." | npx wsc-lint check --stdin
# JSON output for scripting
npx wsc-lint check "**/*.md" --format json
# GitHub Actions annotations
npx wsc-lint check "**/*.md" --format github
# Create a config file
npx wsc-lint initSee the wsc-lint README for full documentation.
- uses: theserverlessdev/wsc/action@master
with:
files: '**/*.md'
max-warnings: 20| Input | Default | Description |
|---|---|---|
files |
**/*.md |
Glob pattern for files to check |
config |
— | Path to .wscrc.json config file |
max-warnings |
unlimited | Max warnings before failing |
only-changed |
false |
Only check files changed in this PR |
The web editor runs in your browser - we never send text to any server. The API and MCP endpoints only process text you explicitly send to them.
.
├── src/
│ ├── core/ # Shared detection engine
│ │ ├── detector.ts # 8 detection algorithms
│ │ ├── words.ts # Word/phrase lists (800+ entries)
│ │ ├── config.ts # Config types, merging, validation
│ │ ├── config-node.ts # Node-only: file loading, discovery
│ │ ├── analyzer.ts # Unified analyzeText() entry point
│ │ └── index.ts # Public API exports
│ ├── docs/ # Documentation content (Markdown files)
│ ├── mcp/
│ │ └── handler.ts # MCP JSON-RPC 2.0 handler
│ ├── lib/
│ │ ├── App.svelte # Main editor page component
│ │ ├── stores/theme.ts # Theme store (light/dark/system)
│ │ └── components/ # UI components (StatsBar, ConfigPanel, etc.)
│ ├── routes/
│ │ ├── +layout.svelte # Shared layout (header, nav, footer)
│ │ ├── api/check/+server.ts # HTTP API endpoint
│ │ ├── mcp/+server.ts # MCP endpoint
│ │ ├── health/+server.ts # Health check endpoint
│ │ ├── docs/+page.svelte # Documentation page
│ │ └── words/+page.svelte # Word library browser
│ └── styles/
│ └── main.scss # Global styles (light + dark themes)
├── mcp-server/ # Standalone stdio MCP server (npm: wsc-mcp)
├── cli/ # CLI tool (npm: wsc-lint)
├── action/ # GitHub Action (composite)
├── tests/ # 341 tests across 18 files
├── static/
│ ├── schema.json # JSON Schema for .wscrc.json
│ ├── llms.txt # AI/LLM discovery file
│ └── llms-full.txt # Detailed LLM context
├── wrangler.toml # Cloudflare Workers config
└── svelte.config.js # SvelteKit configuration
git clone https://github.com/theserverlessdev/wsc.git
cd wsc
npm install
npm run devVisit http://localhost:5173. The API is at /api/check, MCP at /mcp, health at /health.
| Command | Description |
|---|---|
npm run dev |
Start dev server |
npm run build |
Build for production |
npm run check |
Type check with svelte-check |
npm test |
Run all 341 tests |
npm run test:coverage |
Coverage report |
Deployed as a Cloudflare Worker at wsc.theserverless.dev.
npm run build
npx wrangler deploySee CONTRIBUTING.md for development setup, testing, and pull request guidelines.
For substantial changes, please open an issue first.
- Matt Might for the original shell scripts
- Built with SvelteKit and Svelte 5, deployed on Cloudflare Workers
- Logo made with DiffusionBee