# Canonical Party Input

`party.yml` is a campaign-owned roster input. Narratio recognizes the
versioned `narratio.party.v1` document below when it resolves a pipeline,
campaign, and session together.

```yaml
schema_version: narratio.party.v1

characters:
  arannis:
    player:
      name: Eric
    character:
      name: Arannis
      alias:
        - Ari
        - The Grey Owl
      classes:
        - name: wizard
          level: 8
```

`characters` is a non-empty mapping. Each key is a stable character ID using
the configured-artifact key grammar: a lowercase ASCII letter followed by zero
or more lowercase ASCII letters, digits, or underscores. Character order is
preserved where roster order matters.

Every entry has `player.name`, `character.name`, and a non-empty
`character.classes` list. Class entries require a non-empty `name` and may
include a positive integer `level`. The optional, intentionally singular
`character.alias` field is a list. Names, aliases, and class names must be
non-empty, trimmed display strings without control characters. Character names
and aliases must be unique across the full roster under Unicode-aware
case-insensitive comparison; player names may repeat.

The document has exactly one YAML document and accepts no unknown fields. A
wrong or malformed `schema_version` is an error.

## Legacy migration boundary

An unversioned party input remains supported only as opaque legacy reference
material while campaigns migrate. It requires a separate `players_file` and
retains the existing session override behavior. It cannot be mixed with a
canonical party: canonical campaigns must omit `players_file`, and sessions
must not override their party or players inputs.

Use the canonical document for new campaigns. The configuration rules and
source-relative path behavior are defined in the [Configuration Reference](../config.md).