A Personality is a named overlay on top of an Agent — same agent,
same LLM, but a different bundle of prompts injected into the system
block at chat time. VLAN-on-ethernet semantics: ethernet still works
without VLAN; with a VLAN tag, frames are segmented but still ethernet.
Schema additions:
- Prompt.agentId (nullable FK + index, cascade on delete) so prompts
can attach directly to an agent without going through a project.
- Personality { id, name, description, agentId, priority } with
unique (name, agentId).
- PersonalityPrompt join table with per-binding priority override.
- Agent.defaultPersonalityId (SetNull on delete) so an agent can pick
one personality as the default when no --personality flag is passed.
Backwards-compatible by construction: every new column is nullable;
existing rows are valid as-is; the chat.service systemBlock changes
land in Stage 3.
8 new prisma-level assertions in agent-schema.test.ts cover unique
constraints, cascade behavior, the SetNull on defaultPersonalityId,
and shared-prompt-across-personalities. All 16 db tests pass; mcpd
typecheck + 777 mcpd unit tests still green.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
f60f00f1fd