What it can do

Create Timestamp: Compute the SHA-256 hash of the file locally - the file itself is never uploaded, and spArxx.io never stores it. Call this with that hash plus basic file metadata to register a prove

List Evidence: Returns every evidence item owned by the calling account, newest first, as a summary (no full receipt data, call get_evidence for the complete receipt kit on a specific item). Use this

Get Evidence: Returns the complete receipt kit for a single evidence item: hash, file metadata, status, and, once the on-chain job has settled, the blockchain transaction hash and explorer URL. Poll t

Built for human creators - Register a timestamp on Polygon proving you made something, the moment you did. Your file is never uploaded, watermarked, or altered: only its cryptographic fingerprint ever reaches spArxx.io, zero-knowledge by design. What comes back is a timestamp: your independently verifiable record of having registered it first.

Built on MCP (the same open standard Claude and other AI assistants use for secure, authenticated tool access), the spArxx.io server lets your AI register timestamps, check your balance, retrieve receipts, and verify blockchain anchors, mid-conversation, no app-switching. Every timestamp anchors to the Polygon blockchain, independently verifiable forever after ... no trust in spArxx.io required beyond the public chain itself.

spArxx.io is built for human creators, and that shows up in how it's provisioned ... not just in its purpose: connecting via MCP gets your AI access to the tools, but a human still provisions the account behind it. That's a deliberate choice, not unfinished friction. Minimal human involvement is required, but not zero ... that's what keeps the registration meaningful.

At a glance:

Chain: Polygon
Privacy: Zero-knowledge. Your file's contents never reach spArxx.io, only its cryptographic fingerprint does
Cost: 20 spArks (~$0.20) per agentic timestamp (the lowest rate on the platform).
Access: OAuth, human-provisioned account required

create_timestamp	Compute the SHA-256 hash of the file locally - the file itself is never uploaded, and spArxx.io never stores it. Call this with that hash plus basic file metadata to register a provenance timestamp. This deducts spArks from the account (dynamic cost. Call get_pricing or get_balance first if you want to pre-check spend; a 402 response here means ins...
list_evidence	Returns every evidence item owned by the calling account, newest first, as a summary (no full receipt data, call get_evidence for the complete receipt kit on a specific item). Use this to find an evidence_id when the caller only knows a file name, or to check on recent timestamping activity.
get_evidence	Returns the complete receipt kit for a single evidence item: hash, file metadata, status, and, once the on-chain job has settled, the blockchain transaction hash and explorer URL. Poll this after create_timestamp until status is 'submitted', then save the full response alongside the original file as the durable proof-of-timestamp record. This is th...
get_balance	Call this before create_timestamp if you want to pre-check that the account can afford the operation and explain a likely 402 in advance, rather than reacting to one after the fact. Combine with get_pricing to compare balance against cost.
get_pricing	Public pricing reference. Does not require a user credential, only the channel Consumer-Token. Returns the current cost (in spArks) of a timestamp operation and the credits-to-USD exchange rate. Both timestamp_register (standard) and timestamp_register_agentic (MCP agent calls) are always returned, regardless of the caller's own auth, so this is a...
verify_certificate	Unauthenticated. No Consumer-Token or user credential required. Any agent can verify any spArxx.io timestamp proof this way, which makes it a discovery surface as well as a verification tool: given a tx hash from a certificate or receipt kit, this confirms the proof is real and returns the public receipt data (identity claim redaction now follows t...

spArxx.io | Zero-Knowledge Blockchain Timestamping

What it can do

What data it sees

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