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Sweep 25 Sep 2026 · 19:33Z Build v2.1.283 504 read Stable v2.1.274 Latest v2.1.283 Next v2.1.283 Feeds RSS JSON llms.txt llms-full.txt Unofficial
One change · api

Batches changedapi/messages/batches

Nearest release: v2.1.283, published 3 hours after 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+326added
Lines−333removed
From line 33 where the diff opens
First seen 14 Aug 2026 this site's first read of the page
Recorded edits13to this page, all time

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from line 33
3333 
3434 List of requests for prompt completion. Each is an individual request to create a Message.
3535 
36 maxItems: 100000, minItems: 1
36 minItems: 1, maxItems: 100000
3737 
3838 - `custom_id: string`
3939 
from line 41
4141 
4242 Must be unique for each request within the Message Batch.
4343 
44 maxLength: 64, minLength: 1, pattern: ^[a-zA-Z0-9_-]{1,64}$
44 minLength: 1, maxLength: 64, pattern: ^[a-zA-Z0-9_-]{1,64}$
4545 
4646 - `params: object`
4747 
from line 161
161161 
162162 - `document_title: string or null`
163163 
164 maxLength: 500, minLength: 1
164 minLength: 1, maxLength: 500
165165 
166166 - `end_char_index: number`
167167 
from line 181
181181 
182182 - `document_title: string or null`
183183 
184 maxLength: 500, minLength: 1
184 minLength: 1, maxLength: 500
185185 
186186 - `end_page_number: number`
187187 
from line 205
205205 
206206 - `document_title: string or null`
207207 
208 maxLength: 500, minLength: 1
208 minLength: 1, maxLength: 500
209209 
210210 - `end_block_index: number`
211211 
from line 229
229229 
230230 - `title: string or null`
231231 
232 maxLength: 512, minLength: 1
232 minLength: 1, maxLength: 512
233233 
234234 - `url: string`
235235 
from line 385
385385 
386386 - `title: optional string or null`
387387 
388 maxLength: 500, minLength: 1
388 minLength: 1, maxLength: 500
389389 
390390 - `SearchResultBlockParam object`
391391 
from line 449
449449 
450450 - `name: string`
451451 
452 maxLength: 200, minLength: 1
452 minLength: 1, maxLength: 200
453453 
454454 - `cache_control: optional CacheControlEphemeral or null`
455455 
from line 485
485485 
486486 For a toolset member tool_use, the toolset family this member belongs to.
487487 
488 maxLength: 64, minLength: 1, pattern: ^[a-zA-Z0-9_-]+$
488 minLength: 1, maxLength: 64, pattern: ^[a-zA-Z0-9_-]+$
489489 
490490 - `ToolResultBlockParam object`
491491 
from line 521
521521 
522522 - `tool_name: string`
523523 
524 maxLength: 256, minLength: 1, pattern: ^[a-zA-Z0-9_-]{1,256}$
524 minLength: 1, maxLength: 256, pattern: ^[a-zA-Z0-9_-]{1,256}$
525525 
526526 - `cache_control: optional CacheControlEphemeral or null`
527527 
from line 549
549549 
550550 The caller-assigned identifier for this tab, unique within the inventory.
551551 
552 maxLength: 4096, minLength: 1, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
552 minLength: 1, maxLength: 4096, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
553553 
554554 - `title: string`
555555 
from line 575
575575 
576576 Tabs opened and download state changes during this call. "Nothing to report" is expressed by omitting the field, never by an empty list.
577577 
578 maxItems: 200, minItems: 1
578 minItems: 1, maxItems: 200
579579 
580580 - `BrowserStateChangeTabOpened object`
581581 
from line 593
593593 
594594 The `tab_id` of the opened tab, present in `tabs`.
595595 
596 maxLength: 4096, minLength: 1, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
596 minLength: 1, maxLength: 4096, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
597597 
598598 - `BrowserStateChangeDownloadStarted object`
599599 
from line 605
605605 
606606 The caller-assigned identifier for this download, stable across the state changes reporting it.
607607 
608 maxLength: 4096, minLength: 1, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
608 minLength: 1, maxLength: 4096, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
609609 
610610 - `url: string`
611611 
from line 626
626626 
627627 The caller-assigned identifier for this download, stable across the state changes reporting it.
628628 
629 maxLength: 4096, minLength: 1, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
629 minLength: 1, maxLength: 4096, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
630630 
631631 - `url: string`
632632 
from line 638
638638 
639639 Where the executor saved the file, on the executor's filesystem. Only included when another tool in the same environment can read the file at that path.
640640 
641 pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$, maxLength: 4096
641 maxLength: 4096, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
642642 
643643 - `size_bytes: optional number or null`
644644 
from line 656
656656 
657657 The caller-assigned identifier for this download, stable across the state changes reporting it.
658658 
659 maxLength: 4096, minLength: 1, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
659 minLength: 1, maxLength: 4096, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
660660 
661661 - `url: string`
662662 
from line 668
668668 
669669 The failure or cancellation detail, when known.
670670 
671 pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$, maxLength: 4096
671 maxLength: 4096, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
672672 
673673 - `is_error: optional boolean`
674674 
from line 676
676676 
677677 For a toolset member tool_result, the toolset family of the paired tool_use.
678678 
679 maxLength: 64, minLength: 1, pattern: ^[a-zA-Z0-9_-]+$
679 minLength: 1, maxLength: 64, pattern: ^[a-zA-Z0-9_-]+$
680680 
681681 - `ServerToolUseBlockParam object`
682682 
from line 1054
10541054 
10551055 - `tool_name: string`
10561056 
1057 maxLength: 256, minLength: 1, pattern: ^[a-zA-Z0-9_-]{1,256}$
1057 minLength: 1, maxLength: 256, pattern: ^[a-zA-Z0-9_-]{1,256}$
10581058 
10591059 - `cache_control: optional CacheControlEphemeral or null`
10601060 
from line 1095
10951095 
10961096 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
10971097 
1098 - `string`
1099 
10981100 - `"claude-fable-5-1" or "claude-opus-5-5" or "claude-mythos-5-1" or 15 more`
10991101 
11001102 The model that will complete your prompt.
from line 1139
11371139 
11381140 Powerful intelligence for long-running agents and coding
11391141 
1140 - `"claude-mythos-preview"`
1141 
1142 New class of intelligence, strongest in coding and cybersecurity
1143 
11441142 - `"claude-opus-4-6"`
11451143 
11461144 Powerful intelligence for long-running agents and coding
from line 1171
11731171 
11741172 High-performance model for agents and coding
11751173 
1176 - `string`
1174 - `"claude-mythos-preview"`
11771175 
1176 **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit https://docs.anthropic.com/en/docs/resources/model-deprecations for more information.
1177 
1178 New class of intelligence, strongest in coding and cybersecurity
1179 
11781180 - `cache_control: optional CacheControlEphemeral or null`
11791181 
11801182 Top-level cache control automatically applies a cache_control marker to the last cacheable block in the request.
from line 1211
12091211 
12101212 Skill ID
12111213 
1212 maxLength: 64, minLength: 1
1214 minLength: 1, maxLength: 64
12131215 
12141216 - `version: optional string`
12151217 
12161218 Skill version or 'latest' for most recent version
12171219 
1218 maxLength: 64, minLength: 1
1220 minLength: 1, maxLength: 64
12191221 
12201222 - `string`
12211223 
12221224 - `diagnostics: optional DiagnosticsParam or null`
12231225 
1224 Request-level diagnostics. Currently carries the previous response
1225 id for prompt-cache divergence reporting.
1226 Request-level diagnostics. Supply `previous_message_id` to have the response include `diagnostics.cache_miss_reason` explaining any prompt-cache divergence from that prior request.
12261227 
12271228 - `previous_message_id: optional string or null`
12281229 
from line 1253
12521253 
12531254 - `effort: optional "low" or "medium" or "high" or 2 more or null`
12541255 
1255 All possible effort levels.
1256 How much effort the model should put into its response. Higher effort levels may result in more thorough analysis but take longer.
12561257 
1258 Valid values are `low`, `medium`, `high`, `xhigh`, or `max`.
1259 
12571260 - `"low"`
12581261 
12591262 - `"medium"`
from line 1505
15021505 
15031506 This is how the tool will be called by the model and in `tool_use` blocks.
15041507 
1505 maxLength: 128, minLength: 1, pattern: ^[a-zA-Z0-9_-]{1,128}$
1508 minLength: 1, maxLength: 128, pattern: ^[a-zA-Z0-9_-]{1,128}$
15061509 
15071510 - `allowed_callers: optional array of "direct" or "code_execution_20250825" or "code_execution_20260120" or "code_execution_20260521"`
15081511 
from line 1722
17191722 
17201723 - `configs: optional BrowserToolsetConfigs or null`
17211724 
1722 Per-member configuration for `browser_toolset_20260801`: one
1723 optional field per member tool, keyed by the member name — the same
1724 name the member's `tool_use` blocks carry. Every member is an
1725 accepted key, and a member's defaults apply wherever its key is
1726 absent. Unknown keys are rejected: the field set is this toolset
1727 version's complete member set.
1725 Sparse per-member overrides, keyed by member name. Absent, null, and {} are equivalent; a member's defaults apply wherever its key is absent.
17281726 
17291727 - `type: optional BrowserTypeConfig or null`
17301728 
from line 2149
21512149 
21522150 - `configs: optional ComputerToolsetConfigs or null`
21532151 
2154 Per-member configuration for `computer_toolset_20260801`: one
2155 optional field per member tool, keyed by the member name — the same
2156 name the member's `tool_use` blocks carry. Every member is an
2157 accepted key, and a member's defaults apply wherever its key is
2158 absent. Unknown keys are rejected: the field set is this toolset
2159 version's complete member set.
2152 Sparse per-member overrides, keyed by member name. Absent, null, and {} are equivalent; a member's defaults apply wherever its key is absent.
21602153 
21612154 - `type: optional ComputerTypeConfig or null`
21622155 
from line 2503
25102503 
25112504 Maximum number of times the tool can be used in the API request.
25122505 
2513 exclusiveMinimum: 0
2506 minimum: 1
25142507 
25152508 - `strict: optional boolean`
25162509 
from line 2519
25262519 
25272520 The city of the user.
25282521 
2529 maxLength: 255, minLength: 1
2522 minLength: 1, maxLength: 255
25302523 
25312524 - `country: optional string or null`
25322525 
25332526 The two letter [ISO country code](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2) of the user.
25342527 
2535 maxLength: 2, minLength: 2
2528 minLength: 2, maxLength: 2
25362529 
25372530 - `region: optional string or null`
25382531 
25392532 The region of the user.
25402533 
2541 maxLength: 255, minLength: 1
2534 minLength: 1, maxLength: 255
25422535 
25432536 - `timezone: optional string or null`
25442537 
25452538 The [IANA timezone](https://nodatime.org/TimeZones) of the user.
25462539 
2547 maxLength: 255, minLength: 1
2540 minLength: 1, maxLength: 255
25482541 
25492542 - `WebFetchTool20250910 object`
25502543 
from line 2583
25902583 
25912584 Maximum number of tokens used by including web page text content in the context. The limit is approximate and does not apply to binary content such as PDFs.
25922585 
2593 exclusiveMinimum: 0
2586 minimum: 1
25942587 
25952588 - `max_uses: optional number or null`
25962589 
25972590 Maximum number of times the tool can be used in the API request.
25982591 
2599 exclusiveMinimum: 0
2592 minimum: 1
26002593 
26012594 - `strict: optional boolean`
26022595 
from line 2597
26042597 
26052598 - `url_sources: optional WebFetchURLSources or null`
26062599 
2607 Which sources contribute to the set of URLs web fetch may fetch.
2600 Which sources contribute to the set of URLs the tool may fetch. Omitted means every source.
26082601 
2609 Each key is a tagged variant: `user_input` is `all` or `none`; the
2610 two tool filters are `all`, `none`, `only` (only the named tools'
2611 results) or `except` (every result but the named tools'). A named tool
2612 must be declared in this request's `tools[]`.
2613 
26142602 - `client_tool_results: optional WebFetchURLSourceAll or WebFetchURLSourceNone or WebFetchURLSourceOnly or WebFetchURLSourceExcept`
26152603 
26162604 Which client tools' results contribute fetchable URLs: "all", "none", or an only or except list of client tool names from tools[].
from line 2721
27332721 
27342722 Maximum number of times the tool can be used in the API request.
27352723 
2736 exclusiveMinimum: 0
2724 minimum: 1
27372725 
27382726 - `strict: optional boolean`
27392727 
from line 2775
27872775 
27882776 Maximum number of tokens used by including web page text content in the context. The limit is approximate and does not apply to binary content such as PDFs.
27892777 
2790 exclusiveMinimum: 0
2778 minimum: 1
27912779 
27922780 - `max_uses: optional number or null`
27932781 
27942782 Maximum number of times the tool can be used in the API request.
27952783 
2796 exclusiveMinimum: 0
2784 minimum: 1
27972785 
27982786 - `strict: optional boolean`
27992787 
from line 2789
28012789 
28022790 - `url_sources: optional WebFetchURLSources or null`
28032791 
2804 Which sources contribute to the set of URLs web fetch may fetch.
2792 Which sources contribute to the set of URLs the tool may fetch. Omitted means every source.
28052793 
2806 Each key is a tagged variant: `user_input` is `all` or `none`; the
2807 two tool filters are `all`, `none`, `only` (only the named tools'
2808 results) or `except` (every result but the named tools'). A named tool
2809 must be declared in this request's `tools[]`.
2810 
28112794 - `WebFetchTool20260309 object`
28122795 
28132796 Web fetch tool with use_cache parameter for bypassing cached content.
from line 2837
28542837 
28552838 Maximum number of tokens used by including web page text content in the context. The limit is approximate and does not apply to binary content such as PDFs.
28562839 
2857 exclusiveMinimum: 0
2840 minimum: 1
28582841 
28592842 - `max_uses: optional number or null`
28602843 
28612844 Maximum number of times the tool can be used in the API request.
28622845 
2863 exclusiveMinimum: 0
2846 minimum: 1
28642847 
28652848 - `strict: optional boolean`
28662849 
from line 2851
28682851 
28692852 - `url_sources: optional WebFetchURLSources or null`
28702853 
2871 Which sources contribute to the set of URLs web fetch may fetch.
2854 Which sources contribute to the set of URLs the tool may fetch. Omitted means every source.
28722855 
2873 Each key is a tagged variant: `user_input` is `all` or `none`; the
2874 two tool filters are `all`, `none`, `only` (only the named tools'
2875 results) or `except` (every result but the named tools'). A named tool
2876 must be declared in this request's `tools[]`.
2877 
28782856 - `use_cache: optional boolean`
28792857 
28802858 Whether to use cached content. Set to false to bypass the cache and fetch fresh content. Only set to false when the user explicitly requests fresh content or when fetching rapidly-changing sources.
from line 2897
29192897 
29202898 Maximum number of times the tool can be used in the API request.
29212899 
2922 exclusiveMinimum: 0
2900 minimum: 1
29232901 
29242902 - `response_inclusion: optional "full" or "excluded"`
29252903 
from line 2959
29812959 
29822960 Maximum number of tokens used by including web page text content in the context. The limit is approximate and does not apply to binary content such as PDFs.
29832961 
2984 exclusiveMinimum: 0
2962 minimum: 1
29852963 
29862964 - `max_uses: optional number or null`
29872965 
29882966 Maximum number of times the tool can be used in the API request.
29892967 
2990 exclusiveMinimum: 0
2968 minimum: 1
29912969 
29922970 - `response_inclusion: optional "full" or "excluded"`
29932971 
from line 2981
30032981 
30042982 - `url_sources: optional WebFetchURLSources or null`
30052983 
3006 Which sources contribute to the set of URLs web fetch may fetch.
2984 Which sources contribute to the set of URLs the tool may fetch. Omitted means every source.
30072985 
3008 Each key is a tagged variant: `user_input` is `all` or `none`; the
3009 two tool filters are `all`, `none`, `only` (only the named tools'
3010 results) or `except` (every result but the named tools'). A named tool
3011 must be declared in this request's `tools[]`.
3012 
30132986 - `use_cache: optional boolean`
30142987 
30152988 Whether to use cached content. Set to false to bypass the cache and fetch fresh content. Only set to false when the user explicitly requests fresh content or when fetching rapidly-changing sources.
from line 3069
30963069 
30973070 Note that even with `temperature` of `0.0`, the results will not be fully deterministic.
30983071 
3099 maximum: 1, minimum: 0
3072 minimum: 0, maximum: 1
31003073 
31013074 - `top_k: optional number`
31023075 
from line 3093
31203093 
31213094 Recommended for advanced use cases only.
31223095 
3123 maximum: 1, minimum: 0
3096 minimum: 0, maximum: 1
31243097 
31253098### Returns
31263099 
from line 3441
34683441 
34693442 Defaults to `20`. Ranges from `1` to `1000`.
34703443 
3471 default: 20, maximum: 1000, minimum: 1
3444 default: 20, minimum: 1, maximum: 1000
34723445 
34733446### Headers
34743447 
from line 3901
39283901 
39293902 - `container: Container or null`
39303903 
3931 Information about the container used in the request (for the code execution tool)
3904 Information about the container used in this request.
39323905 
3906 This will be non-null if a container tool (e.g. code execution) was used.
3907 
39333908 - `id: string`
39343909 
39353910 Identifier for the container used in this request
from line 3931
39563931 
39573932 Skill ID
39583933 
3959 maxLength: 64, minLength: 1
3934 minLength: 1, maxLength: 64
39603935 
39613936 - `version: string`
39623937 
39633938 The resolved version: a skill version ID for custom skills.
39643939 
3965 maxLength: 64, minLength: 1
3940 minLength: 1, maxLength: 64
39663941 
39673942 - `content: array of ContentBlock`
39683943 
from line 4110
41354110 
41364111 - `text: string`
41374112 
4138 minLength: 0
4139 
41404113 - `ThinkingBlock object`
41414114 
41424115 - `type: "thinking"`
from line 4190
42174190 
42184191 For a toolset member tool_use, the toolset family.
42194192 
4220 maxLength: 64, minLength: 1, pattern: ^[a-zA-Z0-9_-]+$
4193 minLength: 1, maxLength: 64, pattern: ^[a-zA-Z0-9_-]+$
42214194 
42224195 - `ServerToolUseBlock object`
42234196 
from line 4638
46654638 
46664639 - `tool_name: string`
46674640 
4668 maxLength: 256, minLength: 1, pattern: ^[a-zA-Z0-9_-]{1,256}$
4641 minLength: 1, maxLength: 256, pattern: ^[a-zA-Z0-9_-]{1,256}$
46694642 
46704643 - `tool_use_id: string`
46714644 
from line 4656
46834656 
46844657 - `diagnostics: Diagnostics or null`
46854658 
4686 Request-level diagnostics: why the prompt cache could not fully reuse
4687 the prefix of the request named by `diagnostics.previous_message_id`.
4659 Request-level diagnostics. `null` when the request did not supply `diagnostics`, or when it did and no prompt-cache divergence was detected.
46884660 
46894661 - `cache_miss_reason: CacheMissReason or null`
46904662 
from line 4720
47484720 
47494721 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
47504722 
4723 - `string`
4724 
47514725 - `"claude-fable-5-1" or "claude-opus-5-5" or "claude-mythos-5-1" or 15 more`
47524726 
47534727 The model that will complete your prompt.
from line 4764
47904764 
47914765 Powerful intelligence for long-running agents and coding
47924766 
4793 - `"claude-mythos-preview"`
4794 
4795 New class of intelligence, strongest in coding and cybersecurity
4796 
47974767 - `"claude-opus-4-6"`
47984768 
47994769 Powerful intelligence for long-running agents and coding
from line 4796
48264796 
48274797 High-performance model for agents and coding
48284798 
4829 - `string`
4799 - `"claude-mythos-preview"`
48304800 
4801 **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit https://docs.anthropic.com/en/docs/resources/model-deprecations for more information.
4802 
4803 New class of intelligence, strongest in coding and cybersecurity
4804 
48314805 - `role: "assistant"`
48324806 
48334807 Conversational role of the generated message.
from line 4812
48384812 
48394813 - `stop_details: RefusalStopDetails or null`
48404814 
4841 Structured information about a refusal.
4815 Structured information about why model output stopped.
48424816 
4817 This is `null` when the `stop_reason` has no additional detail to report.
4818 
48434819 - `type: "refusal"`
48444820 
48454821 default: refusal
from line 4822
48464822 
48474823 - `category: "cyber" or "bio" or "frontier_llm" or 2 more or null`
48484824 
4849 The policy category that triggered a refusal.
4825 The policy category that triggered the refusal.
48504826 
4827 `null` when the refusal doesn't map to a named category.
4828 
48514829 - `"cyber"`
48524830 
48534831 The request could enable cyber harm, such as malware or exploit development. Benign cybersecurity work can also trigger this category.
from line 5412
54345412 
54355413 - `container: Container or null`
54365414 
5437 Information about the container used in the request (for the code execution tool)
5415 Information about the container used in this request.
54385416 
5417 This will be non-null if a container tool (e.g. code execution) was used.
5418 
54395419 - `id: string`
54405420 
54415421 Identifier for the container used in this request
from line 5442
54625442 
54635443 Skill ID
54645444 
5465 maxLength: 64, minLength: 1
5445 minLength: 1, maxLength: 64
54665446 
54675447 - `version: string`
54685448 
54695449 The resolved version: a skill version ID for custom skills.
54705450 
5471 maxLength: 64, minLength: 1
5451 minLength: 1, maxLength: 64
54725452 
54735453 - `content: array of ContentBlock`
54745454 
from line 5621
56415621 
56425622 - `text: string`
56435623 
5644 minLength: 0
5645 
56465624 - `ThinkingBlock object`
56475625 
56485626 - `type: "thinking"`
from line 5701
57235701 
57245702 For a toolset member tool_use, the toolset family.
57255703 
5726 maxLength: 64, minLength: 1, pattern: ^[a-zA-Z0-9_-]+$
5704 minLength: 1, maxLength: 64, pattern: ^[a-zA-Z0-9_-]+$
57275705 
57285706 - `ServerToolUseBlock object`
57295707 
from line 6149
61716149 
61726150 - `tool_name: string`
61736151 
6174 maxLength: 256, minLength: 1, pattern: ^[a-zA-Z0-9_-]{1,256}$
6152 minLength: 1, maxLength: 256, pattern: ^[a-zA-Z0-9_-]{1,256}$
61756153 
61766154 - `tool_use_id: string`
61776155 
from line 6167
61896167 
61906168 - `diagnostics: Diagnostics or null`
61916169 
6192 Request-level diagnostics: why the prompt cache could not fully reuse
6193 the prefix of the request named by `diagnostics.previous_message_id`.
6170 Request-level diagnostics. `null` when the request did not supply `diagnostics`, or when it did and no prompt-cache divergence was detected.
61946171 
61956172 - `cache_miss_reason: CacheMissReason or null`
61966173 
from line 6231
62546231 
62556232 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
62566233 
6234 - `string`
6235 
62576236 - `"claude-fable-5-1" or "claude-opus-5-5" or "claude-mythos-5-1" or 15 more`
62586237 
62596238 The model that will complete your prompt.
from line 6275
62966275 
62976276 Powerful intelligence for long-running agents and coding
62986277 
6299 - `"claude-mythos-preview"`
6300 
6301 New class of intelligence, strongest in coding and cybersecurity
6302 
63036278 - `"claude-opus-4-6"`
63046279 
63056280 Powerful intelligence for long-running agents and coding
from line 6307
63326307 
63336308 High-performance model for agents and coding
63346309 
6335 - `string`
6310 - `"claude-mythos-preview"`
63366311 
6312 **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit https://docs.anthropic.com/en/docs/resources/model-deprecations for more information.
6313 
6314 New class of intelligence, strongest in coding and cybersecurity
6315 
63376316 - `role: "assistant"`
63386317 
63396318 Conversational role of the generated message.
from line 6323
63446323 
63456324 - `stop_details: RefusalStopDetails or null`
63466325 
6347 Structured information about a refusal.
6326 Structured information about why model output stopped.
63486327 
6328 This is `null` when the `stop_reason` has no additional detail to report.
6329 
63496330 - `type: "refusal"`
63506331 
63516332 default: refusal
from line 6333
63526333 
63536334 - `category: "cyber" or "bio" or "frontier_llm" or 2 more or null`
63546335 
6355 The policy category that triggered a refusal.
6336 The policy category that triggered the refusal.
63566337 
6338 `null` when the refusal doesn't map to a named category.
6339 
63576340 - `"cyber"`
63586341 
63596342 The request could enable cyber harm, such as malware or exploit development. Benign cybersecurity work can also trigger this category.
from line 6695
67126695 
67136696 - `container: Container or null`
67146697 
6715 Information about the container used in the request (for the code execution tool)
6698 Information about the container used in this request.
67166699 
6700 This will be non-null if a container tool (e.g. code execution) was used.
6701 
67176702 - `id: string`
67186703 
67196704 Identifier for the container used in this request
from line 6725
67406725 
67416726 Skill ID
67426727 
6743 maxLength: 64, minLength: 1
6728 minLength: 1, maxLength: 64
67446729 
67456730 - `version: string`
67466731 
67476732 The resolved version: a skill version ID for custom skills.
67486733 
6749 maxLength: 64, minLength: 1
6734 minLength: 1, maxLength: 64
67506735 
67516736 - `content: array of ContentBlock`
67526737 
from line 6904
69196904 
69206905 - `text: string`
69216906 
6922 minLength: 0
6923 
69246907 - `ThinkingBlock object`
69256908 
69266909 - `type: "thinking"`
from line 6984
70016984 
70026985 For a toolset member tool_use, the toolset family.
70036986 
7004 maxLength: 64, minLength: 1, pattern: ^[a-zA-Z0-9_-]+$
6987 minLength: 1, maxLength: 64, pattern: ^[a-zA-Z0-9_-]+$
70056988 
70066989 - `ServerToolUseBlock object`
70076990 
from line 7432
74497432 
74507433 - `tool_name: string`
74517434 
7452 maxLength: 256, minLength: 1, pattern: ^[a-zA-Z0-9_-]{1,256}$
7435 minLength: 1, maxLength: 256, pattern: ^[a-zA-Z0-9_-]{1,256}$
74537436 
74547437 - `tool_use_id: string`
74557438 
from line 7450
74677450 
74687451 - `diagnostics: Diagnostics or null`
74697452 
7470 Request-level diagnostics: why the prompt cache could not fully reuse
7471 the prefix of the request named by `diagnostics.previous_message_id`.
7453 Request-level diagnostics. `null` when the request did not supply `diagnostics`, or when it did and no prompt-cache divergence was detected.
74727454 
74737455 - `cache_miss_reason: CacheMissReason or null`
74747456 
from line 7514
75327514 
75337515 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
75347516 
7517 - `string`
7518 
75357519 - `"claude-fable-5-1" or "claude-opus-5-5" or "claude-mythos-5-1" or 15 more`
75367520 
75377521 The model that will complete your prompt.
from line 7558
75747558 
75757559 Powerful intelligence for long-running agents and coding
75767560 
7577 - `"claude-mythos-preview"`
7578 
7579 New class of intelligence, strongest in coding and cybersecurity
7580 
75817561 - `"claude-opus-4-6"`
75827562 
75837563 Powerful intelligence for long-running agents and coding
from line 7590
76107590 
76117591 High-performance model for agents and coding
76127592 
7613 - `string`
7593 - `"claude-mythos-preview"`
76147594 
7595 **Deprecated**: Will reach end-of-life on June 30, 2026. Please migrate to claude-mythos-5. Visit https://docs.anthropic.com/en/docs/resources/model-deprecations for more information.
7596 
7597 New class of intelligence, strongest in coding and cybersecurity
7598 
76157599 - `role: "assistant"`
76167600 
76177601 Conversational role of the generated message.
from line 7606
76227606 
76237607 - `stop_details: RefusalStopDetails or null`
76247608 
7625 Structured information about a refusal.
7609 Structured information about why model output stopped.
76267610 
7611 This is `null` when the `stop_reason` has no additional detail to report.
7612 
76277613 - `type: "refusal"`
76287614 
76297615 default: refusal
from line 7616
76307616 
76317617 - `category: "cyber" or "bio" or "frontier_llm" or 2 more or null`
76327618 
7633 The policy category that triggered a refusal.
7619 The policy category that triggered the refusal.
76347620 
7621 `null` when the refusal doesn't map to a named category.
7622 
76357623 - `"cyber"`
76367624 
76377625 The request could enable cyber harm, such as malware or exploit development. Benign cybersecurity work can also trigger this category.
from line 7930
79427930 
79437931 - `container: Container or null`
79447932 
7945 Information about the container used in the request (for the code execution tool)
7933 Information about the container used in this request.
79467934 
7935 This will be non-null if a container tool (e.g. code execution) was used.
7936 
79477937 - `id: string`
79487938 
79497939 Identifier for the container used in this request
from line 7960
79707960 
79717961 Skill ID
79727962 
7973 maxLength: 64, minLength: 1
7963 minLength: 1, maxLength: 64
79747964 
79757965 - `version: string`
79767966 
79777967 The resolved version: a skill version ID for custom skills.
79787968 
7979 maxLength: 64, minLength: 1
7969 minLength: 1, maxLength: 64
79807970 
79817971 - `content: array of ContentBlock`
79827972 
from line 8139
81498139 
81508140 - `text: string`
81518141 
8152 minLength: 0
8153 
81548142 - `ThinkingBlock object`
81558143 
81568144 - `type: "thinking"`
from line 8219
82318219 
82328220 For a toolset member tool_use, the toolset family.
82338221 
8234 maxLength: 64, minLength: 1, pattern: ^[a-zA-Z0-9_-]+$
8222 minLength: 1, maxLength: 64, pattern: ^[a-zA-Z0-9_-]+$
82358223 
82368224 - `ServerToolUseBlock object`
82378225 
from line 8667
86798667 
86808668 - `tool_name: string`
86818669 
8682 maxLength: 256, minLength: 1, pattern: ^[a-zA-Z0-9_-]{1,256}$
8670 minLength: 1, maxLength: 256, pattern: ^[a-zA-Z0-9_-]{1,256}$
86838671 
86848672 - `tool_use_id: string`
86858673 
from line 8685
86978685 
86988686 - `diagnostics: Diagnostics or null`
86998687 
8700 Request-level diagnostics: why the prompt cache could not fully reuse
8701 the prefix of the request named by `diagnostics.previous_message_id`.
8688 Request-level diagnostics. `null` when the request did not supply `diagnostics`, or when it did and no prompt-cache divergence was detected.
87028689 
87038690 - `cache_miss_reason: CacheMissReason or null`
87048691 
from line 8721
87348721 
87358722 Approximate number of input tokens that would have been read from cache had the prefix matched the previous request.
87368723 
8737 - `
8724 - `CacheMissMessagesChanged object`
8725 
8726 - `type
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