> ## Documentation Index
> Fetch the complete documentation index at: https://docs.instructorphp.com/llms.txt
> Use this file to discover all available pages before exploring further.

# V1.18.2

# Release Notes - v1.18.2

## Highlights

* Continuation-safe agent state persistence with new serialization helpers.
* MessageStore serialization is now round-trip safe and section-aware.
* Metadata preservation fixes for slim agent state snapshots.

## Behavior Changes

### MessageStore toArray Structure

* `MessageStore::toArray()` now returns a structured payload with `sections` and `parameters` instead of a flat messages list.
* Use `MessageStore::toFlatArray()` to obtain the previous flat messages array format.

## New Features

### Agent Continuation APIs

* Added `AgentState::withUserMessage()` for multi-turn continuation.
* Added `AgentState::forContinuation()` to reset execution state (steps, cache, usage, timing) while preserving conversation history.

### Continuation Serializer

* Added `ContinuationAgentStateSerializer` with `ContinuationSerializationConfig` to persist multi-turn state with retention limits.
* Supports truncation, tool-result omission, and tool-arg redaction while preserving `_metadata`.

## Bug Fixes

### Metadata Preservation

* `SlimAgentStateSerializer` now emits `_metadata` (with `metadata` alias support) so tool calls/results survive round-trips.
* `MessageInput::fromArray()` now accepts `metadata` as a fallback alias for `_metadata`.

### Serialization Round-Trip

* MessageStore serialization now round-trips sections, messages, and parameters without data loss.

## Tests

* Added round-trip tests for MessageStore and continuation serialization.
* Added AgentState continuation tests covering reset semantics and message appending.