ContactHI is an open protocol (CHI/1.0) that solves the most fundamental problem of the agentic era: how should AI agents contact humans, and who gets to decide the rules?
The Problem
AI agents are becoming first-class internet citizens. They book appointments, monitor accounts, execute trades, and escalate decisions. Every one of them needs to reach a human sometimes — but there is no standard, no protocol, and no human-controlled ruleset for how that contact should happen. Left to incumbents, it becomes opt-out spam. ContactHI makes it opt-in by design.
Core Architecture
Three separable layers that can federate independently:
**Layer 1 — Preference Registry (on-chain, CosmWasm)** Humans declare rules: for each sender type × intent, which channels are allowed, at what rate, in what time window. Stored on Cosmos — tamper-proof, globally queryable, owned by the human.
**Layer 2 — Message Protocol (CHI/1.0 open spec)** A standardized envelope with sender DID, Entity Identity ZK proof, intent type, payload, and priority. Five intent types: INFORM, COLLECT, AUTHORIZE, ESCALATE, RESULT. Signed by the sender's key.
**Layer 3 — Federated Router Network** Anyone can run a router node. Routers validate envelopes, query the preference registry, check Nullcone threat feeds, route to the human's declared channels, and write delivery acks to SpacetimeDB.
Why Open Protocol
ContactHI is designed to spread. The spec is open — Twilio implementing it is a win, not a threat. The preference registry is on-chain so no one owns it. The router network is federated so enterprises and privacy operators can self-host. You own your reachability profile regardless of which router delivers your messages.
Integration with Entity Identity
Every CHI envelope includes a ZK proof of the sender's Entity Identity type (CA, AA, LM, RB, etc.) — you know what kind of entity is contacting you without them revealing their identity. This is the trust primitive the protocol is built on.
Tech Stack
CosmWasm (Rust) for on-chain preference registry. SpacetimeDB for real-time ack fabric across the router network. Open TypeScript SDK for developers. Nullcone integration for threat intel at the router layer.