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Kyle Carberry
5630390d94
## Problem
Three bugs with chat summarization (compaction) share a single root
cause: `ReloadMessages` was never wired up in the production
`chatloop.Run()` call.
### Bug 1: Compaction never fires between steps
The inline compaction guard in `chatloop.go` requires both `Compaction`
and `ReloadMessages` to be non-nil:
```go
if opts.Compaction != nil && opts.ReloadMessages != nil {
```
Since `ReloadMessages` was only set in tests, inline compaction was
**dead code in production**. Long multi-step turns could blow through
the context window.
### Bug 2: Compaction only occurs at end of turn
The post-run safety net doesn't check `ReloadMessages`, so it was the
only compaction path that fired:
```go
if !alreadyCompacted && opts.Compaction != nil { // no ReloadMessages check
```
This meant compaction only happened once, after the entire agent turn
finished.
### Bug 3: Agent stops after summarization
After post-run compaction, `Run()` unconditionally returned `nil`.
`processChat` then set the chat status to `waiting` (done). The agent
never had a chance to continue with its fresh summarized context.
## Fix
1. **Wire up `ReloadMessages`** in `chatd.go`: reloads persisted
messages from the database and re-applies system prompts (subagent
instruction, workspace AGENTS.md).
2. **Wrap the step loop in an outer compaction loop**: when compaction
fires on the model's final step (`compactedOnFinalStep`), reload
messages and `continue` the outer loop so the agent re-enters with
summarized context.
3. **Track `compactedOnFinalStep`** to distinguish inline compaction on
the last step (needs re-entry) from inline compaction mid-loop followed
by more tool-call steps (agent already consumed the compacted context,
no re-entry needed).
4. **Add `maxCompactionRetries = 3`** to prevent infinite compaction
loops.
## Testing
- All 7 existing compaction tests pass unchanged.
- Added `PostRunCompactionReEntersStepLoop` test: verifies that when a
text-only response triggers compaction, the outer loop re-enters and the
agent makes a second stream call with fresh context.