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Sweep 22 Sep 2026 · 17:19Z Build v2.1.280 501 read Stable v2.1.267 Latest v2.1.280 Next v2.1.280 Feeds RSS JSON llms.txt Unofficial
Home Docs Claude Developer Platform 18 Sep 2026
One change · api

thinking changed

build-with-claude/thinking

Nearest release: v2.1.277, published 4 hours before this site recorded the change. Shown because the two are within 24 hours of each other. Nothing here says the release caused the edit.

Recorded here
Lines+16added
Lines−17removed
From line 1,163 where the diff opens
First seen 14 Aug 2026 this site's first read of the page
Recorded edits11to this page, all time

The whole hunk

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11631163 
11641164Each model accepts `max_tokens` up to the ceiling listed here. On the [Message Batches API](https://platform.claude.com/docs/en/build-with-claude/batch-processing#extended-output-beta), the `output-300k-2026-03-24` [beta header](https://platform.claude.com/docs/en/api/beta-headers) raises that ceiling for the models with a batches ceiling listed.
11651165 
1166| Model | Max output tokens | Batches beta ceiling |
1167| :---------------- | :---------------- | :------------------- |
1168| Claude Fable 5.1 | 128K | — |
1169| Claude Mythos 5.1 | 128K | — |
1170| Claude Fable 5 | 128K | — |
1171| Claude Mythos 5 | 128K | — |
1172| Claude Opus 5 | 128K | 300K |
1173| Claude Opus 4.8 | 128K | 300K |
1174| Claude Opus 4.7 | 128K | 300K |
1175| Claude Opus 4.6 | 128K | 300K |
1176| Claude Opus 4.5 | 64K | Not available |
1177| Claude Sonnet 5 | 128K | 300K |
1178| Claude Sonnet 4.6 | 128K | 300K |
1179| Claude Sonnet 4.5 | 64K | Not available |
1180| Claude Haiku 4.5 | 64K | Not available |
1181 
1182[Claude Mythos Preview](https://anthropic.com/glasswing) accepts `max_tokens` up to 128K; the Batches beta ceiling is not available for it.
1166| Model | Max output tokens | Batches beta ceiling |
1167| :-------------------- | :---------------- | :------------------- |
1168| Claude Fable 5.1 | 128K | — |
1169| Claude Mythos 5.1 | 128K | — |
1170| Claude Fable 5 | 128K | — |
1171| Claude Mythos 5 | 128K | — |
1172| Claude Mythos Preview | 128K | Not available |
1173| Claude Opus 5 | 128K | 300K |
1174| Claude Opus 4.8 | 128K | 300K |
1175| Claude Opus 4.7 | 128K | 300K |
1176| Claude Opus 4.6 | 128K | 300K |
1177| Claude Opus 4.5 | 64K | Not available |
1178| Claude Sonnet 5 | 128K | 300K |
1179| Claude Sonnet 4.6 | 128K | 300K |
1180| Claude Sonnet 4.5 | 64K | Not available |
1181| Claude Haiku 4.5 | 64K | Not available |
11831182 
11841183See the [models overview](https://platform.claude.com/docs/en/models/overview) for limits on legacy models.
11851184