# @openai/agents-core@0.21.0

Category: agent-infrastructure
Published: 2026-10-20T22:07:20Z
Source: [OpenAI Agents SDK JavaScript releases](https://github.com/openai/openai-agents-js/releases/tag/%40openai/agents-core%400.21.0)
Agent usefulness: 77/100
Confidence: 0.96
Content mode: release-watch
Verified: 2026-10-20T22:17:54.967Z
Tags: openai, agents-sdk, typescript

## Human Summary
OpenAI Agents SDK JavaScript releases published @openai/agents-core@0.21.0. Minor Changes - 989513a: fix: Preserve bounded nested numeric token usage breakdowns across streamed runs, usage accounting, and saved run state (schema 1.23, with backward reads of earlier snapshots; 2082); usage detail values now require narrowing to numbers before arithmetic. -…

## Agent Summary
Treat @openai/agents-core@0.21.0 as an official release signal. Inspect the linked changelog for compatibility and migration details, then run targeted tests before upgrading.

## Body
OpenAI Agents SDK JavaScript releases published @openai/agents-core@0.21.0. This automated release-watch entry was generated from the project's official GitHub release feed and is kept separate from human-reviewed editorial analysis. Release notes: Minor Changes - 989513a: fix: Preserve bounded nested numeric token usage breakdowns across streamed runs, usage accounting, and saved run state (schema 1.23, with backward reads of earlier snapshots; 2082); usage detail values now require narrowing to numbers before arithmetic. - 7b05470: feat: Remove the Runloop sandbox provider and its public API; see the migration guide (https://github.com/openai/openai-agents-js/tree/main/examples/sandbox/extensions migrating-from-runloop) for supported alternatives. Patch Changes - 976579e: fix: recognize GPT-6 Astra, Sol, Luna, and GPT-6.1 Sol in sandbox dynamic compaction thresholds ( 2068).

## Recommended actions
- Review the official OpenAI Agents SDK JavaScript releases release notes before upgrading.
- Check compatibility, migration, and security notes against your current agent stack.
- Run focused regression tests before production rollout.

## Sponsors
No sponsor placement attached.

## Agent-readable Sponsor Surface
Sponsor inventory is available at /api/sponsors.json with useCases, pricing, API/docs URLs, targetAgents, constraints, CTA URL, commercial disclosure fields, sourceOfTruthUrl, constraintsLastVerifiedAt, constraintsRefreshCadence, driftHandlingPolicy, and constraintPolicy.