Create a Message Batch changedapi/beta/messages/batches/create
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Recorded here
Lines+70added
Lines−22removed
From line
16
where the diff opens
First seen
14 Aug 2026
this site's first read of the page
Recorded edits30to this page, all time
The whole hunk
from line 16, old and new numbered
/
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1616
1717 - `string`
1818
19 - `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 38 more`
19 - `"message-batches-2024-09-24" or "prompt-caching-2024-07-31" or "computer-use-2024-10-22" or 41 more`
2020
2121 - `"message-batches-2024-09-24"`
2222
from line 100
100100
101101 - `"ce-user-management-2026-07-13"`
102102
103 - `"mid-conversation-output-config-2026-07-01"`
104
105 - `"thinking-binding-controls-2026-08-01"`
106
107 - `"mid-conversation-system-clear-at-2026-08-21"`
108
103109- `"anthropic-user-profile-id": optional string`
104110
105111 The user profile ID to attribute the requests in this batch to. Use when acting on behalf of a party other than your organization. Requires the `user-profiles` beta header. Applies to every request in the batch; an individual request whose `user_profile_id` body field conflicts with this header is errored.
from line 1418
14121418
14131419 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
14141420
1415 - `"claude-sonnet-5" or "claude-fable-5" or "claude-mythos-5" or 12 more`
1421 - `"claude-fable-5-1" or "claude-mythos-5-1" or "claude-sonnet-5" or 14 more`
14161422
14171423 The model that will complete your prompt.
14181424
14191425 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
14201426
1427 - `"claude-fable-5-1"`
1428
1429 Frontier intelligence for ambitious tasks across coding, scientific discovery, and enterprise workflows
1430
1431 - `"claude-mythos-5-1"`
1432
1433 Our most capable model for cybersecurity and biology research, available through trusted access programs
1434
14211435 - `"claude-sonnet-5"`
14221436
14231437 High-performance model for coding and agents
from line 1512
14981512
14991513 - `"system"`
15001514
1515 - `clear_at: optional "next_user_message" or "never" or null`
1516
1517 How long this system message's text stays in front of the model. `"never"` (the default) renders it on every request that includes it. `"next_user_message"` renders it only for the user turn it follows: once a later `role: "user"` message exists in `messages` the message stays in the array (send it unchanged) but is no longer shown to the model. Only permitted on `role: "system"` messages.
1518
1519 - `"next_user_message"`
1520
1521 - `"never"`
1522
1523 - `output_config: optional BetaSystemMessageOutputConfig or null`
1524
1525 Per-message output configuration on a role:"system" input message.
1526
1527 Fields here apply per-turn; `format` remains top-level only. An
1528 empty `{}` is accepted on a message that carries content; a message
1529 with neither content nor output_config fields is rejected.
1530
1531 - `effort: optional "low" or "medium" or "high" or 2 more or null`
1532
1533 All possible effort levels.
1534
1535 - `"low"`
1536
1537 - `"medium"`
1538
1539 - `"high"`
1540
1541 - `"xhigh"`
1542
1543 - `"max"`
1544
15011545 - `model: Model`
15021546
15031547 The model that will complete your prompt.
from line 1844
18001844
18011845 - `type: "enabled"`
18021846
1847 - `block_binding: optional BetaThinkingBlockBinding or null`
1848
1849 Controls for block binding: what happens when a thinking block this
1850 request sends back fails the conversation check. Every field is optional;
1851 an empty object means every default.
1852
1853 - `prefix_mismatch_behavior: optional BetaThinkingPrefixMismatchBehavior or null`
1854
1855 What happens when a thinking block in `messages` fails the conversation
1856 check: it was created in a different conversation, or the messages before
1857 it have changed since. `"error"` (the default) fails the request with a
1858 400 error. `"drop_block"` removes the failing blocks and the request
1859 proceeds; the model no longer sees the dropped reasoning.
1860
1861 - `"error"`
1862
1863 - `"drop_block"`
1864
18031865 - `display: optional "summarized" or "omitted" or "updates" or null`
18041866
18051867 Controls how thinking content appears in the response. When set to `summarized`, thinking is returned normally. When set to `omitted`, thinking content is redacted but a signature is returned for multi-turn continuity. Defaults to `summarized`.
from line 1880
18181880
18191881 - `type: "adaptive"`
18201882
1883 - `block_binding: optional BetaThinkingBlockBinding or null`
1884
1885 Controls for block binding: what happens when a thinking block this
1886 request sends back fails the conversation check. Every field is optional;
1887 an empty object means every default.
1888
18211889 - `display: optional "summarized" or "omitted" or "updates" or null`
18221890
18231891 Controls how thinking content appears in the response. When set to `summarized`, thinking is returned normally. When set to `omitted`, thinking content is redacted but a signature is returned for multi-turn continuity. Defaults to `summarized`.
from line 2387
23192387
23202388 - `type: "browser_toolset_20260801"`
23212389
2322 - `allowed_callers: optional array of "direct" or "code_execution_20250825" or "code_execution_20260120" or "code_execution_20260521"`
2323
2324 - `"direct"`
2325
2326 - `"code_execution_20250825"`
2327
2328 - `"code_execution_20260120"`
2329
2330 - `"code_execution_20260521"`
2331
23322390 - `cache_control: optional BetaCacheControlEphemeral or null`
23332391
23342392 Create a cache control breakpoint at this content block.
from line 3012
29543012 via `configs.zoom.enabled`.
29553013
29563014 - `type: "computer_toolset_20260801"`
2957
2958 - `allowed_callers: optional array of "direct" or "code_execution_20250825" or "code_execution_20260120" or "code_execution_20260521"`
2959
2960 - `"direct"`
2961
2962 - `"code_execution_20250825"`
2963
2964 - `"code_execution_20260120"`
2965
2966 - `"code_execution_20260521"`
29673015
29683016 - `cache_control: optional BetaCacheControlEphemeral or null`
29693017
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