# CompactionSummary

**Kind:** Interface

**Source:** [`atloria-monorepo/libs/agent-core/src/context/compaction-types.ts`](https://github.com/sherkety/atloria/blob/main/atloria-monorepo/libs/agent-core/src/context/compaction-types.ts#L25)

Smart Compaction Types

Structured schema for model-based context compaction.
The CompactionSummary is a persistent, evolving document that captures
everything the agent needs to continue working after context compression.

Anchored Iterative Summarization (Factory.ai pattern):
- First compaction: summarize full history into CompactionSummary v1
- Subsequent compactions: merge NEW items into existing summary (delta merge)
- Code snippets are NEVER summarized — preserved verbatim

## Properties

| Property | Type |
|---|---|
| `sessionGoal` | `string` |
| `progress` | `{
    /** Tasks/steps already completed */
    completed: string[];
    /** What the agent is currently working on */
    inProgress: string;
    /** Known remaining steps */
    remaining: string[];
    /** Things preventing progress */
    blockers: string[];
  }` |
| `fileOperations` | `Array<{
    path: string;
    action: 'created' | 'modified' | 'read' | 'deleted';
    /** What was done or learned from this file */
    keyDetails: string;
  }>` |
| `decisions` | `Array<{
    decision: string;
    rationale: string;
  }>` |
| `errors` | `Array<{
    error: string;
    resolved: boolean;
    resolution?: string;
  }>` |
| `preservedCode` | `Array<{
    file: string;
    snippet: string;
    why: string;
  }>` |
| `domainState` | `Record<string, string>` |