> ## Documentation Index
> Fetch the complete documentation index at: https://ctrlrun-docs-python-3-13-3-14.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Principal

> Who is acting: an agent, optionally on behalf of a human.

`ctrlrun.Principal` — class, defined at `src/ctrlrun/action.py:139`

```python theme={null}
from ctrlrun import Principal
```

```python theme={null}
class Principal
    def __init__(agent: str, user: str | None = None, claims: Mapping[str, ClaimValue] = (lambda: NO_CLAIMS)(), issuer: str | None = None, expires_at: datetime | None = None)
```

Who is acting: an agent, optionally on behalf of a human.

`claims`, `issuer` and `expires_at` are what an `IdentityProvider` verified (SPEC-v0.3 §2.1).
None of the three is part of the canonical form (§2.2): an approval binds to an action hash,
and a hash that moved when a token rotated would invalidate it for a reason no human could
see and no agent could fix.

## Next

* [Python API index](/docs/reference/api/index).
* [Get started](/docs/get-started/quickstart) · [Why](/docs/why).