---
name: fpf-skill:planning-update-plan
description: Updates a PlanItem by recording variance, preserving the audit trail.
version: 0.1.0
allowed_tools: []
---
# planning/update-plan Kernel
## Context
This skill handles **Plan Iteration**. In FPF, you update a plan by creating a NEW edition (or delta) that explicitly records the *variance* from the baseline. You never mute the history.
## Instructions
Given a previous `SlotFillingsPlanItem` and a requested change (Constraint Update), generate the new plan edition.
### 1. Invariants
- **Immutability**: Do NOT modify the original object. Return a new object.
- **Traceability**: The new object must reference the `previous_edition_ref`.
- **Reasoning**: You must include a `variance_reason` explaining WHY the change occurred (e.g., "User added constraint X").
### 2. Output Schema
```typescript
{
kind: "SlotFillingsPlanItem",
// ... (standard fields updated)
previous_edition_ref: string, // URI of the previous plan
variance_record: {
reason: string,
delta: {
// Describe what slots changed
// e.g. "removed Slot X, added Slot Y"
}
}
}
```
