---
status: open
parent: "[[027-pi-subagents-implementation-spec-task]]"
blocked-by:
  - "[[046-pi-subagents-minimal-tracer-bullet-task]]"
tags:
  - ticket/task/afk
---

# Implement fork context mode

## Question

Add fork context mode so a spawn can give the worker the parent active-branch transcript snapshot and delegated-role wrapper while independent context remains clean by default.

## What to build

Implement the second version-one context mode.
A forked worker should start from the active branch session snapshot and receive a small delegated-role wrapper with the per-call prompt.
Independent workers should remain transcript-clean.
Named agents that declare `allowedContexts` should reject disallowed spawn overrides.

## Acceptance criteria

- [ ] `fork` serializes the parent session header and active branch entries into a child-startable session.
- [ ] The forked worker receives the parent active-branch context plus the delegated request wrapper.
- [ ] `independent` workers still do not receive parent transcript context.
- [ ] `allowedContexts` rejects disallowed context overrides.
- [ ] Tests or manual checks distinguish forked and independent context visibility.

## Implementation Notes

Do not summarize, strip tool output, or compact before spawning.
Let child Pi handle normal compaction.