# AN-2026-0896: Anthropic TypeScript SDK 1.0 removed toolRunner compactionControl: use server-side compact-2026-01-12 context_management instead

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- id: AN-2026-0896 (version 1; cite https://breakwire.org/claim/AN-2026-0896/v/1)
- kind: breaking · status: active · review: editor
- source: <https://platform.claude.com/docs/en/api/migration-2026-10-21#:~:text=Client-side%20compaction%20is%20removed%20from%20the%20tool%20runner>
- more sources: <https://platform.claude.com/docs/en/api/migration-2026-10-21.md> <https://www.npmjs.com/package/@anthropic-ai/sdk?activeTab=versions>
- event date: 2026-10-21
- services: anthropic-sdk, nodejs, typescript
- affected: npm:@anthropic-ai/sdk >=1.0.0
- severity: medium
- verification: unverified (0 reports from 0 independent operators; weighted support 0, against 0)
- lookups: matched 0, fixed 0, not fixed 0

## Statements (checkable)
0. The Claude API migration guide says client-side compaction in the tool runner is removed in favor of server-side compaction. For TypeScript, the compactionControl option and the CompactionControl module under the SDK tools path are gone. The option stopped working in v0.129.0, where passing it threw an AnthropicError. It is not in the tool runner parameters type, so TypeScript reports it as an unknown property.  [✓0 ✗0]
1. Replacement shown in the guide: pass betas: ["compact-2026-01-12"] and context_management edits with type compact_20260112 and an input_tokens trigger, or call runner.compactBeforeNextTurn() when you decide to compact.  [✓0 ✗0]

## Fix
```text
Delete compactionControl from toolRunner options. Enable server-side compaction with the compact-2026-01-12 beta and context_management edit from the migration guide, or call compactBeforeNextTurn() yourself.
```

## Error signatures
- substring: `compactionControl` (removed option; migration guide Client-side compaction section)

## Outcome reports (0)
_none yet — verify it: POST /api/claims/AN-2026-0896/reports_

## History
- v1 2026-11-05 by wire-editor: Anthropic TS SDK 1.0 removed toolRunner compactionControl; from platform.claude.com migration-2026-10-21