Chainletter Labs provides an API that stamps any file to the blockchain, creating a verifiable, tamper‑proof record of its content, issuer, and timestamp. The service handles IPFS pinning, hashing, and on‑chain indexing in a single call, enabling developers, LLMs, and autonomous agents to programmatically verify provenance without needing wallets or tokens. It also offers batch stamping for high‑volume issuance and a CLI tool for easy integration.
Funding
Funding not disclosed
Founders
Product
Problem
Organizations lack a simple way to create immutable, verifiable records of digital files, making it difficult to prove authorship, integrity, and timestamp without complex blockchain integration or managing crypto wallets.
Solution
Chainletter Labs offers a machine‑friendly API that automatically pins files to IPFS, computes a cryptographic hash, and records the hash, issuer identity, and timestamp on a public blockchain in a single request. The service abstracts away wallet management, token handling, and blockchain infrastructure, allowing agents, LLMs, and developers to issue tamper‑proof stamps at scale. Stamps can be verified instantly via a GET endpoint that checks the on‑chain record, confirming who created the file, that it has not been altered, and when it was recorded. Batch stamping enables high‑volume issuance, while a no‑code portal and CLI tools provide alternative integration paths. All records remain publicly verifiable forever, independent of Chainletter’s servers.
Target Audience
Primary customers are developers, AI agents, and enterprises that need to issue and verify authentic digital credentials, such as educational institutions, legal firms, AI skill marketplaces, and supply‑chain managers.
Features
- Single‑call webhook that handles IPFS pinning, hash generation, and on‑chain stamping
- No‑wallet, no‑token requirement; authentication via secret API keys
- Immediate verification endpoint returning issuer, timestamp, and integrity status
- Batch stamping (PATCH) for aggregating multiple files into one on‑chain transaction
- SDK‑agnostic; works with any programming language or agent runtime
- Supporting tools: CredCLI (CLI for bulk credential issuance), DSoul marketplace integration, and Asset Tracker for provenance of physical assets
- Public blockchain storage ensures records are immutable and verifiable indefinitely