---
title: "Key concepts"
description: "The vocabulary of a brokered signup, as short summaries that link to the canonical glossary."
image: "https://docs.agentregistrar.dev/og/docs-default.png"
---

> Documentation Index
> Fetch the complete documentation index at: https://docs.agentregistrar.dev/llms.txt
> Use this file to discover all available pages before exploring further.

# Key concepts

The [glossary](/reference/glossary/) holds the canonical definition of every term this site uses, one per term. This page is the quickstart's short version: a summary line per term, each linking to the glossary section that owns the detail. It defines nothing the glossary does not.

## Roles and records

- **Human owner**: the verified human principal behind every agent. [Glossary](/reference/glossary/#roles-and-records)
- **Agent (sub-identity)**: a broker record with an id (`agt_...`), a dedicated inbox address and delegated scopes; the identity the model acts under. [Glossary](/reference/glossary/#roles-and-records)
- **Harness**: the client that connects to the broker's MCP endpoint and runs the agent. [Glossary](/reference/glossary/#roles-and-records)
- **Broker**: the service that verifies the human, holds the sub-identity and inbox, mints assertions, records acceptances and receipts, and exposes the MCP tools. [Glossary](/reference/glossary/#roles-and-records)
- **Relying party (provider)**: a service that accepts brokered agent signups by publishing discovery and verifying an assertion. It may publish an optional broker-issued verification credential. [Glossary](/reference/glossary/#roles-and-records)
- **Provider verification credential**: the broker-issued RP attestation binding origin, audience, identity, level and keys. [Glossary](/reference/glossary/#protocol-artifacts)
- **Delegated scopes**: the permissions the agent holds, embedded in `delegation.scopes`. [Glossary](/reference/glossary/#roles-and-records)

## Artifacts

- **Discovery document**: the identity-only JSON at `/.well-known/agent-signup.json` on the provider's origin. [Glossary](/reference/glossary/#protocol-artifacts)
- **Assertion**: a short-lived Ed25519-signed JWT that proves the agent, the verified human owner and the delegated ToS acceptance. [Glossary](/reference/glossary/#protocol-artifacts)
- **Receipt (`signup_token`)**: the provider's RP-signed proof of signup, recording the identity facts, the accepted ToS and an optional context pointer. No `exp` in v1.2. [Glossary](/reference/glossary/#protocol-artifacts)
- **Context guide**: a hash-pinned URL to the provider's post-signup guide, usually a `SKILL.md`. [Glossary](/reference/glossary/#protocol-artifacts)
- **Ledger**: the acceptance ledger and the service signups ledger, two records with one name. [Glossary](/reference/glossary/#protocol-artifacts)
- **Kill switch**: the per-agent revocation control in the portal. [Glossary](/reference/glossary/#operations)

## Term to where it lives

| Term | What it is | Where it lives |
| :--- | :--- | :--- |
| Human owner | Verified human principal | Broker account, `human.id` in the assertion |
| Agent | Sub-identity with an inbox | Broker record, `agent.id` in the assertion |
| Harness | MCP client holding the session | Your machine |
| Discovery | Identity-only JSON | Provider origin, `/.well-known/agent-signup.json` |
| Terms | Exact legal text plus hash | `terms` in discovery |
| Assertion | Short-lived signed JWT | Returned by `identity_signup` or `identity_prove`, sent to the provider |
| Receipt | RP-signed proof of signup | `signup_token` in the signup response |
| Provider verification credential | Optional broker-signed identity | `rp_attestation` in discovery |
| Context guide | Hash-pinned vendor guide | Provider origin, linked by `context.url` |
| Acceptance | Durable consent event | Broker ledger, one per agent and terms hash |
| Signup proof | Recorded account attribution | Broker ledger, written by Contract F or `identity_record_signup` |
| Revocation | Human kill switch | Broker, sets `revoked` |
| Suspension | Operator protective action | Broker, sets `suspended` |

## Next

- [How it works](/start/how-it-works/) puts these terms in order.
- [Trust and limits](/start/trust-and-limits/) explains what revocation and the ledger do not cover.
- The [specification](https://github.com/agentregistrar/spec/blob/v1.2.0/agent-identity-v1.md) defines the field-level contract.

Source: https://docs.agentregistrar.dev/start/concepts/index.mdx