orphograph

Anchor any file to the Bitcoin blockchain in about ten seconds. For photographers, journalists, indie creators, and developers who need to prove a file existed before a given moment — especially before an AI model saw it. Files never leave the browser; only the 32-byte SHA-256 fingerprint is submitted. Free tier (3 anchors/24h), $19 Writer Pack (10 anchors), $9/mo Standing Order (unlimited), $19/mo Creator (capture-time app + API + verifier badge).

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Quick demo

Four steps a developer can run from a terminal, no signup, no install beyond curl and shasum.

1. Compute the SHA-256 of any file on disk:

   shasum -a 256 ~/Pictures/my-photo.jpg
   # → 3f8c1b...  my-photo.jpg
   

2. Submit the hash to the public anchor endpoint:

   curl -sS -X POST https://orphograph.com/api/anchor \
        -H "Content-Type: application/json" \
        -d '{"hash_hex":"<paste the 64-char hex digest>"}'
   

   The response is a JSON receipt with a receipt_id and a list of the OpenTimestamps calendars that accepted the submission.

3. Pull the receipt back later by ID (or visit /r/<id>):

   curl -sS https://orphograph.com/api/verify/<receipt_id>
   

4. Verify offline against the original file with the standalone verifier (no orphograph code, MIT, ~100 lines of stdlib Python):

   # Single file with an inclusion proof:
   python3 dist/orphograph-verify/verify.py file \
       --file ~/Pictures/my-photo.jpg \
       --proof receipts/<receipt_id>/proof.json
   # Whole folder against its manifest:
   python3 dist/orphograph-verify/verify.py folder \
       --dir ~/Pictures/evidence \
       --manifest receipts/<receipt_id>/manifest.json
   

   The verifier re-hashes the file (or walks the folder) locally and confirms the result reproduces the manifest's root. Add --ots <path>.ots to also invoke the OpenTimestamps client and check the chain witness references the same root.

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MCP server (Model Context Protocol)

Orphograph ships an MCP server: a single stdlib-only Python file (682 lines, MIT) that implements the Model Context Protocol — JSON-RPC 2.0 over stdio, protocol version 2024-11-05, with the initialize, tools/list, and tools/call methods implemented directly, no SDK — so AI agents and MCP hosts (Claude Code, Claude Desktop, or any MCP client) can anchor and verify files as tool calls.

Listed in the official MCP registry as io.github.Orphograph/orphograph.

MCP tools exposed (full JSON Schemas in mcp/manifest.json):

Tool	What it does
orphograph_anchor_file	Hash a local file (SHA-256/SHA-512 computed in-process) and anchor the fingerprints to Bitcoin via OpenTimestamps. The file body never leaves the machine.
orphograph_anchor_folder	Build an RFC-6962 Merkle manifest over a folder and anchor one root that covers every file.
orphograph_anchor_output	Anchor an AI agent's generated output at creation time — provenance receipts for agent actions.
orphograph_verify_receipt	Verify an existing receipt against the OpenTimestamps calendars and the Bitcoin chain. No API key required.
orphograph_list_vault	List the authenticated subscriber's anchored receipts.

Quickstart (stdio transport):

curl -sSL https://orphograph.com/mcp/orphograph_mcp.py -o orphograph_mcp.py
claude mcp add orphograph -- python3 orphograph_mcp.py

The free tier needs no API key; set ORPHO_API_KEY to use vault features. An MCPB bundle is attached to release mcp-v0.1.0, and mcp/Dockerfile builds a minimal container for MCP directory crawlers — the server starts and answers MCP introspection with no configuration. Full tool schemas and options: mcp/README.md.

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Architecture

Python 3.11+ stdlib only on the server (http.server, urllib, hashlib, json, secrets, fcntl) — zero pip dependencies in the anchor engine. Vanilla HTML + CSS + JS on the client, hashing via WebCrypto SubtleCrypto.digest so file bytes never leave the browser. Each anchor fans out a single 32-byte POST to five independent OpenTimestamps calendars (a.pool, b.pool, alice, finney, btc.catallaxy); the calendars batch many users' hashes into a single Merkle root and write the root to Bitcoin roughly hourly, which is why our marginal on-chain cost is effectively zero. The .ots proofs are stored per-receipt and verify against the public Bitcoin chain forever, with or without us. Bitcoin custody is receive-only: a single watch-only address printed in btc_address.txt accepts payments; no signing keys live on production hosts.

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Why this exists

By spring 2026 a large share of new images circulating online are AI-generated or AI-modified. Watermarks can be stripped, C2PA labels can be re-signed, EXIF is one shell command away from being anything you want. What survives that is cryptographic proof — a Bitcoin block that already existed at a known time, with the hash of your file committed inside it. Orphograph is the cheapest, most boring way to put a fingerprint of your work into that block before anyone disputes it. Long-form on the thesis: /blog/written-by-an-ai.

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Privacy properties

What touches what, in one table.

Datum	Stays on your machine	Sent to server	Submitted to OTS calendars	Notes
File bytes	yes	never	never	WebCrypto hashes locally
SHA-256 (32 bytes)	yes	yes	yes	The only thing on-chain
SHA-512 sibling (64 bytes)	yes	yes	no	Quantum hedge; stored in receipt only
Filename / label	yes	opt-in	no	Off by default; pass --label to include
Email address	yes	only when needed	no	Required only for Pack delivery + Personal subscriptions
IP address	n/a	truncated to /24 (IPv4) or /48 (IPv6)	no	Full IPs are never persisted

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Repo structure

orphograph/
├── server/                       Python stdlib HTTP server + anchor engine
│   ├── engine.py                anchor + verify core (the file in this README)
│   ├── app.py                   ThreadingHTTPServer with /api/anchor /api/verify
│   ├── verify_cli.py            standalone receipt verifier (no engine imports)
│   ├── auth.py                  magic-link tokens + HttpOnly session cookies
│   ├── credits.py               append-only Pack claim-code ledger
│   ├── stripe_webhook.py        HMAC signature verify + idempotent handler
│   ├── subscriptions.py         Personal-tier state derived from Stripe
│   ├── mailer.py                Resend HTTP send (inert when key unset)
│   ├── rate_limit.py            persistent token bucket
│   ├── file_lock.py             fcntl.flock helper for ledger atomicity
│   ├── upgrade_worker.py        OTS upgrade fetcher (cron)
│   ├── expire_worker.py         free-tier receipt pruner (cron)
│   └── gdpr.py                  /api/me/export + /api/me/delete
│
├── web/                          vanilla HTML/CSS/JS — no bundler, no framework
│   ├── index.html, app.js       landing + drop zone + verify section
│   ├── account.html, account.js Personal-tier dashboard
│   ├── signin.html, signin.js   magic-link request form
│   ├── receipt.html, receipt.js print-friendly receipt at /r/<id>
│   ├── style.css                dark glassmorphism, neon-green accent
│   └── terms.html, privacy.html legal pages
│
├── content/blog/                 markdown blog posts (SEO + manifesto)
│   ├── written-by-an-ai.md
│   └── prove-photo-existed-before-ai.md
│
├── tests/                        pytest suite (~98 cases, all stdlib)
│   └── test_*.py                engine / verifier / credits / rate_limit /
│                                 auth / stripe / subscriptions / gdpr / ui
│
├── marketplace/orphograph-plugin/  Claude Code plugin
│   ├── README.md
│   └── skills/anchor, skills/verify
│
├── lightroom-plugin/             Adobe Lightroom Classic plugin (Lua)
│
├── capture/                      desktop capture daemon (Creator tier)
│
├── dist/orphograph-verify/       MIT standalone verifier (vendorable)
│
├── scripts/                      operational helpers
│   ├── smoke_test.sh            end-to-end live OTS calendar test
│   ├── dev_setup.sh             fresh-clone sanity check
│   ├── init_volume.sh           container entrypoint (Fly)
│   ├── upgrade_cron.sh          OTS upgrade scheduler
│   ├── expire_cron.sh           free-tier expiry scheduler
│   └── refund_pack.py           zero a claim code after a Stripe refund
│
└── deploy/                       deploy + ops docs
    ├── FLY_PREFLIGHT.md
    ├── EMAIL_AND_LEGAL_COMPLIANCE.md
    ├── PAYOUT.md
    ├── RUNBOOK.md
    └── launch_drafts/

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Local dev

git clone https://github.com/orphograph/orphograph ~/orphograph
cd ~/orphograph
bash scripts/dev_setup.sh           # offline checks + verifier roundtrip
python3 server/app.py               # serves http://127.0.0.1:8989

Run the test suite at any time:

python3 -m pytest tests/ -q

The smoke test hits live OTS calendars and requires network:

bash scripts/smoke_test.sh

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Production deploy

Single-container Fly.io with a mounted volume for receipts/ and the JSONL ledgers; Stripe webhook verification, Resend for transactional email, CSP default-src 'self'. Step-by-step in deploy/FLY_PREFLIGHT.md.

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Pricing

Tier	Price	What's included
Free	$0	3 anchors per 24 hours per IP-prefix
Writer Pack	$19 one-time	10 anchors, claim code by email, never expires, skips rate limit
Standing Order	$9/mo or $60/yr	Unlimited anchors, email delivery, account dashboard, anchor history
Creator	$19/mo	Personal + Orphograph Capture (capture-time desktop app) + API access + verifier badge

The $19 / $9 price points are set deliberately low. The wedge is browser-based UX plus the open-source verifier — not the cryptography, which is the public OpenTimestamps protocol.

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License

• dist/orphograph-verify/ — MIT. Vendor it, ship it, audit it. This is the trust artifact: a receipt produced today must verify against Bitcoin five years from now even if orphograph.com no longer exists.
• marketplace/orphograph-plugin/ — MIT.
• Everything else — private until launch decisions settle. The founder retains the option to open-source after six months of customer signal.

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On the guarantee

The privacy contract of Orphograph is structural, not promissory. Files are hashed in the user's browser; only the SHA-256 (and SHA-512) fingerprint is transmitted. The server cannot reconstruct, identify, or retransmit the file, because it never receives the file. This property holds independently of who maintains the code.