removeduplicates.org

A focused static tool for removing duplicates from lines, lists, pasted spreadsheet data, CSV files, and local XLSX workbooks, deployed as a Cloudflare Worker with Static Assets.

Links:

• Website: RemoveDuplicates.org

• Excel tool: Remove duplicates from Excel online

• Source code: suvadadepolo-blip/remove-duplicates

License: MIT

Use it from an AI agent (MCP)

A hosted MCP server is available at https://removeduplicates.org/mcp (Streamable HTTP). There is nothing to install and no API key or account. It is listed in the Official MCP Registry as org.removeduplicates/remove-duplicates.

Claude Code:

claude mcp add --transport http removeduplicates https://removeduplicates.org/mcp

Cline (cline_mcp_settings.json):

{
  "mcpServers": {
    "removeduplicates": {
      "type": "streamableHttp",
      "url": "https://removeduplicates.org/mcp"
    }
  }
}

Cursor (mcp.json) takes the same mcpServers entry without type. VS Code (.vscode/mcp.json):

{
  "servers": {
    "removeduplicates": {
      "type": "http",
      "url": "https://removeduplicates.org/mcp"
    }
  }
}

Clients that only speak stdio can bridge with npx mcp-remote https://removeduplicates.org/mcp.

The server has one read-only tool, remove_duplicates. It takes text (up to 128 KiB) plus optional format (auto, lines, table), ignoreCase, trim, removeEmpty, keep (first, last), order (preserve, sort), compare (row, a column index, or a list of indices) and header, and returns the cleaned text with counts. Each call is processed in memory and nothing is stored. For .xlsx workbooks, use the Excel tool, which runs only in the browser.

Related MCP server: Structured Data Validator & Transformer MCP Server

Product boundary

• Line and table-aware deduplication runs in browser memory; larger inputs are streamed to a same-origin Web Worker in responsive chunks.

• Excel and Google Sheets rows can be pasted as TSV, while quoted CSV/TSV files can be opened up to the same 5 MB local limit.

• The Excel tool accepts only macro-free .xlsx files, compares an entire row or a stable combination of selected columns, and creates the cleaned workbook in a dedicated Module Worker.

• XLSX package limits are 10 MiB compressed, 2,000 ZIP entries, 100 MiB declared expanded data, 500,000 workbook cells, and 250,000 cells in the selected sheet. Formula row shifts and intersecting merged ranges are blocked.

• SheetJS CE 0.20.3 is pinned under public/vendor/sheetjs-0.20.3/ with its official source URLs, license, and SHA-256 receipt. It is lazy-loaded only after a valid XLSX passes local ZIP preflight and is never requested by the homepage.

• The website does not upload or persist text or workbook contents a user opens. The only server-side processing is the optional /mcp endpoint, which handles text an AI agent sends for that one request and stores nothing.

• No account, database, analytics, advertising, external font, or third-party browser runtime is included.

• Cloudflare still processes ordinary HTTP metadata needed to deliver and protect the site; the Privacy copy states this boundary directly.

• Terms and Privacy are real direct pages, enhanced into an in-page dialog when JavaScript is available.

Agent and answer-engine surfaces

• robots.txt names the major AI crawlers and declares Content-Signal: search=yes, ai-input=yes, ai-train=yes.

• /llms.txt and /llms-full.txt (with /llm.txt redirects) describe the site for language models.

• Every page has a Markdown twin (/index.md, /excel.md, /privacy.md, /terms.md), also served for Accept: text/markdown. HTML routes send Vary: Accept and RFC 8288 Link headers for the API catalog, llms.txt, the agent-skills index, and the Markdown alternate.

• /.well-known/api-catalog (RFC 9727), /.well-known/mcp/server-card.json, /.well-known/agent-skills/index.json with remove-duplicates/SKILL.md, and /.well-known/ai-catalog.json.

• /mcp is a stateless Streamable HTTP MCP server with one tool, remove_duplicates, capped at 128 KiB of text per call. The homepage registers the same tool through WebMCP when the browser exposes navigator.modelContext; that path runs locally in the tab. Both share public/js/agent-tool.js and the site's dedupe.js engine.

• server.json is the Official MCP Registry entry org.removeduplicates/remove-duplicates. Namespace ownership is proven over HTTP by /.well-known/mcp-registry-auth (Ed25519 public key); the private half lives only in the gitignored local.env.txt.

• node scripts/build-agent-files.mjs regenerates the server card, the skill digest, and llms-full.txt; npm run check fails when they are stale.

Commands

npm run check
npm test
npm run verify
npm run preview
npm run qa:browser
npm run benchmark:xlsx
npm run check:http
npm run deploy

Runtime preview, the XLSX benchmark, browser QA, downloaded-file readback, and Lighthouse belong on OpenClaw. Port 3630 is reserved for the managed preview. Deployment uses the project-scoped Cloudflare wrapper one directory above; credentials never live in this project.

Repository hygiene

• Runtime artifacts stay out of Git: output/, .codex-results/, .wrangler/, logs, and .DS_Store.

• Secret-bearing files stay out of Git: .env*, local.env.txt, and *.env.txt; only placeholder templates such as .env.example may be committed.

• Local planning and provider evidence stay out of Git: EXCEL_PLAN.md, IMPROVEMENT_PLAN.md, PROJECT_STATE.md, UTILITY_BASELINE.md, and ops/.

• public/vendor/sheetjs-0.20.3/ is intentionally vendored with its upstream license, source receipt, and SHA-256 checks.

Cloudflare shape

• Worker: removeduplicates-org

• Static assets: public/

• Worker entry point: src/worker.js

• Static asset binding: ASSETS, with run_worker_first: true

• Live Workers.dev staging URL: https://removeduplicates-org.whatmyname.workers.dev/

• Canonical production domain: https://removeduplicates.org/

• Redirecting production alias: https://www.removeduplicates.org/

The Worker owns /excel, direct legal routes, public HTTP-to-HTTPS and canonical-host redirects, method handling, branded 404s, cache policy, HSTS, a hash-pinned CSP, and Workers.dev noindex protection. Excel path case and trailing-slash variants canonicalize to /excel in the same one-hop redirect as scheme or host changes. The Worker accepts only GET and HEAD.

Production release

The active Cloudflare Zone and wrangler.jsonc contain exactly these two custom_domain routes:

1. removeduplicates.org

2. www.removeduplicates.org

The Worker returns a 308 from www to the apex while preserving path and query. A partial route state is invalid, and no Zone Redirect Rule is used. The production apex, redirect alias, TLS, HTTP matrix, five-viewport browser suite, and Lighthouse are recorded as passing in the project state and production deployment ledger.