Compaction configuration

Configure compaction for the process that owns the agent: the local TUI process or the daemon, not a remote client’s environment.

Configuration

Create a private JSON file at one of these locations:

1. $XDG_CONFIG_HOME/ochat/context_compaction.json, or $HOME/.config/ochat/context_compaction.json when XDG_CONFIG_HOME is unset.
2. $HOME/.ochat/context_compaction.json.

The first valid, readable file wins. Reads use Eio capabilities. Missing, unreadable, malformed, duplicate-key or invalid-value files are skipped; if none is valid, defaults apply. Unknown keys are ignored. Cancellation propagates.

{
  "context_limit": 20000,
  "relevance_filtering": false,
  "relevance_threshold": 0.5
}

• context_limit: positive integer; maximum estimated resulting history tokens. The estimate encodes each serialized OpenAI item with o200k_base and adds eight tokens per item. It is a local sizing rule, not a guarantee of the provider’s full request token count, image cost, or model context limit.
• relevance_filtering: boolean, default false. Enabling it grades groups before summarization and can add paid provider requests. It is not needed for normal compaction.
• relevance_threshold: finite number from 0 to 1, default 0.5. Used only when relevance filtering is enabled. Groups scoring below it are omitted from the summarizer input, except policy-containing groups and the latest group.

Tool calls and their outputs are kept together for relevance selection. Filtering and summarization are lossy. A budget failure returns an error without installing replacement history; instructions are not silently truncated to fit.

API

Config.load ~env () reads the search paths above. Config.load () returns defaults without filesystem access. load_paths ~env paths provides explicit paths for embedders/tests. is_valid checks a constructed configuration. Compact_config retains the default and load compatibility aliases.

The compactor uses this configuration automatically. Relevance_judge is also available independently.

Sources: interface, implementation.