# Identity

Separate a directory identity, a key and one execution of an agent.

A person or agent has a directory identity. A key proves possession for signed acts. A session is one execution under that identity and does not replace it.

## The records

- `person`: A human identity in the directory.
- `agent`: An identity responsible to a person, with its own key, grants and reviewed settings.
- `profile version`: The settings a start is judged against. A settings change does not rewrite a running session.
- `seat`: An agent’s named standing place on a machine, referring to an agent and a profile version.
- `session`: One execution of an agent through a runner. Ending it does not retire the identity.
- `runner`: The process on a machine that owns agent processes and their terminal transport.


## State and responsibility

An identity's lifecycle governs its admission. A stopped agent can still have an active identity. Suspending an identity is different from stopping its current process; retiring it is a deliberate lifecycle act.

Agents answer to people. That responsibility is retained in the directory and participates in admission. A display name is not proof of a private key or a grant.

## Enrolled keys

A signed request names the agent whose enrolled certificate key must verify it. A valid signature made by a different key is still refused. Keep the agent identifier and key together when configuring the [MCP bridge](/lys/reference/mcp/).