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

# Experimental features

Experimental features in FluffBuzz are **opt-in preview surfaces**. They are
behind explicit flags because they still need real-world mileage before they
deserve a stable default or a long-lived public contract.

Treat them differently from normal config:

* Keep them **off by default** unless the related doc tells you to try one.
* Expect **shape and behavior to change** faster than stable config.
* Prefer the stable path first when one already exists.
* If you are rolling FluffBuzz out broadly, test experimental flags in a smaller
  environment before baking them into a shared baseline.

## Currently documented flags

| Surface                  | Key                                                       | Use it when                                                                                                    | More                                                                                          |
| ------------------------ | --------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------- |
| Local model runtime      | `agents.defaults.experimental.localModelLean`             | A smaller or stricter local backend chokes on FluffBuzz's full default tool surface                            | [Local Models](/gateway/local-models)                                                         |
| Memory search            | `agents.defaults.memorySearch.experimental.sessionMemory` | You want `memory_search` to index prior session transcripts and accept the extra storage/indexing cost         | [Memory configuration reference](/reference/memory-config#session-memory-search-experimental) |
| Structured planning tool | `tools.experimental.planTool`                             | You want the structured `update_plan` tool exposed for multi-step work tracking in compatible runtimes and UIs | [Gateway configuration reference](/gateway/configuration-reference#toolsexperimental)         |

## Local model lean mode

`agents.defaults.experimental.localModelLean: true` is a pressure-release valve
for weaker local-model setups. It trims heavyweight default tools like
`browser`, `cron`, and `message` so the prompt shape is smaller and less brittle
for small-context or stricter OpenAI-compatible backends.

That is intentionally **not** the normal path. If your backend handles the full
runtime cleanly, leave this off.

## Experimental does not mean hidden

If a feature is experimental, FluffBuzz should say so plainly in docs and in the
config path itself. What it should **not** do is smuggle preview behavior into a
stable-looking default knob and pretend that is normal. That's how config
surfaces get messy.

## Related

* [Features](/concepts/features)
* [Release channels](/install/development-channels)