# Verifyum

> Verifyum creates privacy-preserving file proofs on Solana Mainnet. AI agents and automated tools can use the public HTTP API without an account, wallet, payment, API key, or Bearer token.

## Agent quick start

- Read the local file and calculate its SHA-256 digest on the agent's own machine.
- Generate a fresh 32-byte random nonce and encode it as 43-character unpadded Base64url.
- Build the exact Verifyum version 2 private manifest.
- Canonicalize the manifest with RFC 8785 JCS.
- Calculate the domain-separated commitment from UTF8("verifyum:commitment:v2\n") followed by the canonical manifest.
- Keep the original file, raw file hash, nonce, filename, and private manifest local.
- POST only the final `sha256:<64 lowercase hex>` commitment to `https://api.verifyum.com/v2/anchor`.
- Reuse one stable idempotency key for retries of the same request.
- Poll the returned status URL until `finalized` or `failed`.

Do not send an Authorization header for public access. Never use Verifyum's operations M2M token as a client credential.

## Limits and availability

Public proof creation is currently free. AI SENSE AS pays the Solana network fee. A hard ceiling allows at most ten new anchor reservations per rolling hour per IP. Lower daily per-IP, per-client, global, queue, wallet-balance, and signer-budget limits may apply. Honor HTTP 429 and every Retry-After header.

## Canonical resources

- Agent guide: https://verifyum.com/docs/agent-api.md
- Human-readable agent page: https://verifyum.com/agents
- OpenAPI 3.1 description: https://verifyum.com/openapi.json
- Anchor request schema: https://verifyum.com/schema/anchor-request-v2.json
- Private manifest schema: https://verifyum.com/schema/manifest-v2.json
- Public proof schema: https://verifyum.com/schema/proof-v2.json
- Optional Witness membership schema: https://verifyum.com/schema/witness-proof-membership-v1.json
- Browser protocol implementation: https://verifyum.com/assets/verifyum-protocol.js
- Service health: https://api.verifyum.com/health
- Metadata verification keys: https://verifyum.com/.well-known/verifyum-service-keys.json
- MCP endpoint (Streamable HTTP, no key): https://api.verifyum.com/mcp

## Agent decision records

An agent can seal its own operating state: system instructions, the exact prompt, model and version, parameters, tool calls, and the resulting output, assembled into one document. Hash that document locally and anchor only the commitment. The record stays on the agent's own infrastructure; Verifyum never receives it. A later reviewer recomputes the hash and matches it against the Solana transaction, so a record that was rewritten or backdated will not match. The proof shows the record existed unchanged at that time. It does not prove the agent truly ran with those parameters. Anchor a per-case or daily record, or the head of a local hash chain, rather than every single decision.

## Witness Layer

Verifyum publishes supplemental evidence around finalized proofs: hourly and daily checkpoints witnessed by OpenTimestamps on Bitcoin, a public GitHub checkpoint log, the Internet Archive, and Certificate Transparency. External services receive only aggregate checkpoint roots, never a file, hash, nonce or proof ID. Human-readable explanation: https://verifyum.com/witness

- Checkpoint document: https://verifyum.com/witness/checkpoints/{hourly|daily}/{batch-id}.json
- Channel receipts: https://verifyum.com/witness/receipts/{hourly|daily}/{batch-id}.json

Channel states are pending, confirmed, unavailable or failed. A pending or missing witness does not invalidate the Protocol v2 Solana proof.

## Optional Witness membership

After finalization, a caller that already knows the proof ID may request
https://api.verifyum.com/v2/proofs/{proof-id}/witnesses or
https://{proof-id}.verifyum.com/.well-known/verifyum-witnesses.json. There is
no listing endpoint. HTTP 404 means no supplemental membership is available
and does not invalidate the Protocol v2 proof. A membership currently proves
only inclusion in a Verifyum checkpoint; it does not claim external-channel
confirmation.

## MCP integration

A hosted MCP endpoint is live at https://api.verifyum.com/mcp. It is stateless Streamable HTTP with no account or API key, and exposes verifyum_get_proof, verifyum_verify_public_proof, and verifyum_anchor_commitment with the same limits and retry rules as the HTTP API. The endpoint accepts only a commitment, an idempotency key, or a public proof ID. A remote MCP server must not accept original files or private manifest fields. File hashing and private-draft creation belong in a local MCP process on the agent's machine.

## Proof boundary

A finalized proof shows that a commitment to the exact file bytes existed no later than the estimated Solana block time. It does not by itself prove authorship, ownership, signature validity, legal status, or the truth of the file's contents.