π Watermark Finder β find, mark, and strip hidden text watermarks. Open source, MIT.
Detects six distinct covert channels with exact character offsets, not guesses: Unicode tag payloads, variation-selector encoding, zero-width binary/markers, homoglyph substitution, bidi controls, and repetition stamps. Also verifies C2PA content credentials (Adobe, Leica, Google-signed manifests) β and keeps "integrity" (did the bytes change?) strictly separate from "trust" (is the signer who they claim?), because a forged certificate verifies perfectly too.
It scores writing register (how much prose reads like unedited assistant output) with visible uncertainty ranges and per-feature contributions β and refuses a verdict below ~15 words rather than fake precision. That score measures register, not authorship, and the README says so louder than I'm saying it here.
Two deploy modes: a hosted engine (FastAPI on a HF Space) behind a Cloudflare Worker, or a fully client-side build compiled to WebAssembly via Pyodide β the document never leaves the browser tab in that mode.
304 tests across four suites, real CI on every push, no accounts (anonymous HMAC-token workspace).