Resolve

The problem

A2A discovery assumes the calling agent already knows a domain: it fetches the Agent Card from a well-known path on that domain. A person's agent usually starts with something else, such as the phone number printed on a bill, a brand name, or a support email address.

There is no public mapping from a phone number to an agent endpoint, so agents fall back to dialing the number and talking.

How it works

1. A business claims its identifiers (phone numbers, domains, brand names) and proves it controls each one.
2. Resolve stores the mapping from each identifier to the business's Agent Card.
3. Before dialing, a calling agent queries Resolve and receives the verified endpoint.
4. If the business has no endpoint, the agent learns that immediately and uses the normal channel.

Open standards

The A2A well-known URI (/.well-known/agent-card.json) covers discovery when you already know the domain. Resolve covers the identifiers the web does not, and adds proof of control.

Availability

In development. Public lookups of domains are live at resolve.emissar.ai: read-only, from the Agent Cards that websites publish, as EmissarBot finds them, updated daily. Phone numbers, brand names and claims by businesses come later.

Read the specification: Emissar Resolve v0.1.

Questions

How will you prove someone controls a phone number?

The verification methods are published in the Resolve specification, a draft for comment. The registry does not accept claims yet.

Will Resolve be public?

Yes. Lookups are public and anonymous, the same way DNS is: GET https://resolve.emissar.ai/v0/domain/ followed by a domain. Claiming an identifier will require verification.