DiffMint by Harlo

Compare two texts by line, word or character. Get structured ops, a unified diff, an escaped HTML redline and a similarity score, or apply a unified patch. Deterministic, stateless, with a REST API and an MCP server.

Try it

Mode lineswordschars Compare

API

curl -s https://diffmint.mike-tusa.workers.dev/v1/diff -H 'content-type: application/json' \
  -d '{"a":"one\ntwo\n","b":"one\n2\n","formats":["ops","unified"]}'

• POST /v1/diff: ops, unified diff (lines mode), HTML redline, stats
• POST /v1/patch: apply a unified diff
• POST /v1/similarity: 0-1 similarity ratio
• GET /v1/info: modes and limits

For AI agents

Remote MCP server (Streamable HTTP, no auth needed for the free tier): https://diffmint.mike-tusa.workers.dev/mcp. Tools: diff_text, apply_patch, text_similarity. Also llms.txt and OpenAPI 3.1.

{
  "mcpServers": {
    "diffmint": {
      "type": "http",
      "url": "https://diffmint.mike-tusa.workers.dev/mcp"
    }
  }
}

Plans

• Free: $0/mo, 1,000 calls/month
• BASIC: $5/mo, 25,000 calls/month Buy
• PRO: $15/mo, 250,000 calls/month Buy

Honest limits

Deterministic diff (Myers algorithm via jsdiff), not an AI or semantic comparison. Limits per side: lines mode 64 KB and 1,000 lines, words mode 8 KB, chars mode 4 KB. If the texts need more than 250 inserted plus deleted units, the API returns 422 too_different instead of a partial diff. Patches up to 64 KB apply to text up to 64 KB. No 3-way merge, no binary files. Stateless: text is not stored or logged; no URL fetching.