Messages changedapi/beta/messages
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.
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Lines−2,862removed
From line
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First seen
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from line 245
245245
246246 - `document_title: string or null`
247247
248 maxLength: 500, minLength: 1
248 minLength: 1, maxLength: 500
249249
250250 - `end_char_index: number`
251251
from line 265
265265
266266 - `document_title: string or null`
267267
268 maxLength: 500, minLength: 1
268 minLength: 1, maxLength: 500
269269
270270 - `end_page_number: number`
271271
from line 289
289289
290290 - `document_title: string or null`
291291
292 maxLength: 500, minLength: 1
292 minLength: 1, maxLength: 500
293293
294294 - `end_block_index: number`
295295
from line 313
313313
314314 - `title: string or null`
315315
316 maxLength: 512, minLength: 1
316 minLength: 1, maxLength: 512
317317
318318 - `url: string`
319319
from line 469
469469
470470 - `title: optional string or null`
471471
472 maxLength: 500, minLength: 1
472 minLength: 1, maxLength: 500
473473
474474 - `BetaSearchResultBlockParam object`
475475
from line 533
533533
534534 - `name: string`
535535
536 maxLength: 200, minLength: 1
536 minLength: 1, maxLength: 200
537537
538538 - `cache_control: optional BetaCacheControlEphemeral or null`
539539
from line 569
569569
570570 For a toolset member tool_use, the toolset family this member belongs to.
571571
572 maxLength: 64, minLength: 1, pattern: ^[a-zA-Z0-9_-]+$
572 minLength: 1, maxLength: 64, pattern: ^[a-zA-Z0-9_-]+$
573573
574574 - `BetaToolResultBlockParam object`
575575
from line 605
605605
606606 - `tool_name: string`
607607
608 maxLength: 256, minLength: 1, pattern: ^[a-zA-Z0-9_-]{1,256}$
608 minLength: 1, maxLength: 256, pattern: ^[a-zA-Z0-9_-]{1,256}$
609609
610610 - `cache_control: optional BetaCacheControlEphemeral or null`
611611
from line 633
633633
634634 The caller-assigned identifier for this tab, unique within the inventory.
635635
636 maxLength: 4096, minLength: 1, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
636 minLength: 1, maxLength: 4096, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
637637
638638 - `title: string`
639639
from line 659
659659
660660 Tabs opened and download state changes during this call. "Nothing to report" is expressed by omitting the field, never by an empty list.
661661
662 maxItems: 200, minItems: 1
662 minItems: 1, maxItems: 200
663663
664664 - `BetaBrowserStateChangeTabOpened object`
665665
from line 677
677677
678678 The `tab_id` of the opened tab, present in `tabs`.
679679
680 maxLength: 4096, minLength: 1, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
680 minLength: 1, maxLength: 4096, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
681681
682682 - `BetaBrowserStateChangeDownloadStarted object`
683683
from line 689
689689
690690 The caller-assigned identifier for this download, stable across the state changes reporting it.
691691
692 maxLength: 4096, minLength: 1, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
692 minLength: 1, maxLength: 4096, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
693693
694694 - `url: string`
695695
from line 710
710710
711711 The caller-assigned identifier for this download, stable across the state changes reporting it.
712712
713 maxLength: 4096, minLength: 1, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
713 minLength: 1, maxLength: 4096, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
714714
715715 - `url: string`
716716
from line 722
722722
723723 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.
724724
725 pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$, maxLength: 4096
725 maxLength: 4096, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
726726
727727 - `size_bytes: optional number or null`
728728
from line 740
740740
741741 The caller-assigned identifier for this download, stable across the state changes reporting it.
742742
743 maxLength: 4096, minLength: 1, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
743 minLength: 1, maxLength: 4096, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
744744
745745 - `url: string`
746746
from line 752
752752
753753 The failure or cancellation detail, when known.
754754
755 pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$, maxLength: 4096
755 maxLength: 4096, pattern: ^[^\x00-\x1f\x7f-\x9f\u2028\u2029]*$
756756
757757 - `is_error: optional boolean`
758758
from line 760
760760
761761 For a toolset member tool_result, the toolset family of the paired tool_use.
762762
763 maxLength: 64, minLength: 1, pattern: ^[a-zA-Z0-9_-]+$
763 minLength: 1, maxLength: 64, pattern: ^[a-zA-Z0-9_-]+$
764764
765765 - `BetaServerToolUseBlockParam object`
766766
from line 1192
11921192
11931193 - `tool_name: string`
11941194
1195 maxLength: 256, minLength: 1, pattern: ^[a-zA-Z0-9_-]{1,256}$
1195 minLength: 1, maxLength: 256, pattern: ^[a-zA-Z0-9_-]{1,256}$
11961196
11971197 - `cache_control: optional BetaCacheControlEphemeral or null`
11981198
from line 1384
13841384
13851385 This is how the tool will be called by the model and in `tool_use` blocks.
13861386
1387 maxLength: 128, minLength: 1, pattern: ^[a-zA-Z0-9_-]{1,128}$
1387 minLength: 1, maxLength: 128, pattern: ^[a-zA-Z0-9_-]{1,128}$
13881388
13891389 - `allowed_callers: optional array of "direct" or "code_execution_20250825" or "code_execution_20260120" or "code_execution_20260521"`
13901390
from line 1635
16351635
16361636 - `configs: optional BetaBrowserToolsetConfigs or null`
16371637
1638 Per-member configuration for `browser_toolset_20260801`: one
1639 optional field per member tool, keyed by the member name — the same
1640 name the member's `tool_use` blocks carry. Every member is an
1641 accepted key, and a member's defaults apply wherever its key is
1642 absent. Unknown keys are rejected: the field set is this toolset
1643 version's complete member set.
1638 Sparse per-member overrides, keyed by member name. Absent, null, and {} are equivalent; a member's defaults apply wherever its key is absent.
16441639
16451640 - `type: optional BetaBrowserTypeConfig or null`
16461641
from line 2256
22612256
22622257 - `configs: optional BetaComputerToolsetConfigs or null`
22632258
2264 Per-member configuration for `computer_toolset_20260801`: one
2265 optional field per member tool, keyed by the member name — the same
2266 name the member's `tool_use` blocks carry. Every member is an
2267 accepted key, and a member's defaults apply wherever its key is
2268 absent. Unknown keys are rejected: the field set is this toolset
2269 version's complete member set.
2259 Sparse per-member overrides, keyed by member name. Absent, null, and {} are equivalent; a member's defaults apply wherever its key is absent.
22702260
22712261 - `type: optional BetaComputerTypeConfig or null`
22722262
from line 2610
26202610
26212611 Maximum number of times the tool can be used in the API request.
26222612
2623 exclusiveMinimum: 0
2613 minimum: 1
26242614
26252615 - `strict: optional boolean`
26262616
from line 2626
26362626
26372627 The city of the user.
26382628
2639 maxLength: 255, minLength: 1
2629 minLength: 1, maxLength: 255
26402630
26412631 - `country: optional string or null`
26422632
26432633 The two letter [ISO country code](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2) of the user.
26442634
2645 maxLength: 2, minLength: 2
2635 minLength: 2, maxLength: 2
26462636
26472637 - `region: optional string or null`
26482638
26492639 The region of the user.
26502640
2651 maxLength: 255, minLength: 1
2641 minLength: 1, maxLength: 255
26522642
26532643 - `timezone: optional string or null`
26542644
26552645 The [IANA timezone](https://nodatime.org/TimeZones) of the user.
26562646
2657 maxLength: 255, minLength: 1
2647 minLength: 1, maxLength: 255
26582648
26592649 - `BetaWebFetchTool20250910 object`
26602650
from line 2690
27002690
27012691 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.
27022692
2703 exclusiveMinimum: 0
2693 minimum: 1
27042694
27052695 - `max_uses: optional number or null`
27062696
27072697 Maximum number of times the tool can be used in the API request.
27082698
2709 exclusiveMinimum: 0
2699 minimum: 1
27102700
27112701 - `strict: optional boolean`
27122702
from line 2704
27142704
27152705 - `url_sources: optional BetaWebFetchURLSources or null`
27162706
2717 Which sources contribute to the set of URLs web fetch may fetch.
2707 Which sources contribute to the set of URLs the tool may fetch. Omitted means every source.
27182708
2719 Each key is a tagged variant: `user_input` is `all` or `none`; the
2720 two tool filters are `all`, `none`, `only` (only the named tools'
2721 results) or `except` (every result but the named tools'). A named tool
2722 must be declared in this request's `tools[]`.
2723
27242709 - `client_tool_results: optional BetaWebFetchURLSourceAll or BetaWebFetchURLSourceNone or BetaWebFetchURLSourceOnly or BetaWebFetchURLSourceExcept`
27252710
27262711 Which client tools' results contribute fetchable URLs: "all", "none", or an only or except list of client tool names from tools[].
from line 2828
28432828
28442829 Maximum number of times the tool can be used in the API request.
28452830
2846 exclusiveMinimum: 0
2831 minimum: 1
28472832
28482833 - `strict: optional boolean`
28492834
from line 2882
28972882
28982883 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.
28992884
2900 exclusiveMinimum: 0
2885 minimum: 1
29012886
29022887 - `max_uses: optional number or null`
29032888
29042889 Maximum number of times the tool can be used in the API request.
29052890
2906 exclusiveMinimum: 0
2891 minimum: 1
29072892
29082893 - `strict: optional boolean`
29092894
from line 2896
29112896
29122897 - `url_sources: optional BetaWebFetchURLSources or null`
29132898
2914 Which sources contribute to the set of URLs web fetch may fetch.
2899 Which sources contribute to the set of URLs the tool may fetch. Omitted means every source.
29152900
2916 Each key is a tagged variant: `user_input` is `all` or `none`; the
2917 two tool filters are `all`, `none`, `only` (only the named tools'
2918 results) or `except` (every result but the named tools'). A named tool
2919 must be declared in this request's `tools[]`.
2920
29212901 - `BetaWebFetchTool20260309 object`
29222902
29232903 Web fetch tool with use_cache parameter for bypassing cached content.
from line 2944
29642944
29652945 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.
29662946
2967 exclusiveMinimum: 0
2947 minimum: 1
29682948
29692949 - `max_uses: optional number or null`
29702950
29712951 Maximum number of times the tool can be used in the API request.
29722952
2973 exclusiveMinimum: 0
2953 minimum: 1
29742954
29752955 - `strict: optional boolean`
29762956
from line 2958
29782958
29792959 - `url_sources: optional BetaWebFetchURLSources or null`
29802960
2981 Which sources contribute to the set of URLs web fetch may fetch.
2961 Which sources contribute to the set of URLs the tool may fetch. Omitted means every source.
29822962
2983 Each key is a tagged variant: `user_input` is `all` or `none`; the
2984 two tool filters are `all`, `none`, `only` (only the named tools'
2985 results) or `except` (every result but the named tools'). A named tool
2986 must be declared in this request's `tools[]`.
2987
29882963 - `use_cache: optional boolean`
29892964
29902965 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 3004
30293004
30303005 Maximum number of times the tool can be used in the API request.
30313006
3032 exclusiveMinimum: 0
3007 minimum: 1
30333008
30343009 - `response_inclusion: optional "full" or "excluded"`
30353010
from line 3066
30913066
30923067 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.
30933068
3094 exclusiveMinimum: 0
3069 minimum: 1
30953070
30963071 - `max_uses: optional number or null`
30973072
30983073 Maximum number of times the tool can be used in the API request.
30993074
3100 exclusiveMinimum: 0
3075 minimum: 1
31013076
31023077 - `response_inclusion: optional "full" or "excluded"`
31033078
from line 3088
31133088
31143089 - `url_sources: optional BetaWebFetchURLSources or null`
31153090
3116 Which sources contribute to the set of URLs web fetch may fetch.
3091 Which sources contribute to the set of URLs the tool may fetch. Omitted means every source.
31173092
3118 Each key is a tagged variant: `user_input` is `all` or `none`; the
3119 two tool filters are `all`, `none`, `only` (only the named tools'
3120 results) or `except` (every result but the named tools'). A named tool
3121 must be declared in this request's `tools[]`.
3122
31233093 - `use_cache: optional boolean`
31243094
31253095 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 3104
31343104
31353105 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
31363106
3107 - `string`
3108
31373109 - `"claude-fable-5-1" or "claude-opus-5-5" or "claude-mythos-5-1" or 15 more`
31383110
31393111 The model that will complete your prompt.
from line 3148
31763148
31773149 Powerful intelligence for long-running agents and coding
31783150
3179 - `"claude-mythos-preview"`
3180
3181 New class of intelligence, strongest in coding and cybersecurity
3182
31833151 - `"claude-opus-4-6"`
31843152
31853153 Powerful intelligence for long-running agents and coding
from line 3180
32123180
32133181 High-performance model for agents and coding
32143182
3215 - `string`
3183 - `"claude-mythos-preview"`
32163184
3185 **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.
3186
3187 New class of intelligence, strongest in coding and cybersecurity
3188
32173189 - `name: "advisor"`
32183190
32193191 Name of the tool.
from line 3224
32523224
32533225 Maximum number of times the tool can be used in the API request.
32543226
3255 exclusiveMinimum: 0
3227 minimum: 1
32563228
32573229 - `strict: optional boolean`
32583230
from line 3315
33433315
33443316 Name of the MCP server to configure tools for
33453317
3346 maxLength: 255, minLength: 1
3318 minLength: 1, maxLength: 255
33473319
33483320 - `cache_control: optional BetaCacheControlEphemeral or null`
33493321
from line 3425
34533425
34543426 The name of the MCP server this listing came from, as `mcp_servers` declares it.
34553427
3456 maxLength: 255, minLength: 1
3428 minLength: 1, maxLength: 255
34573429
34583430 - `tools: array of BetaMCPToolParam`
34593431
from line 3507
35353507
35363508 - `effort: optional "low" or "medium" or "high" or 2 more or null`
35373509
3538 All possible effort levels.
3510 How much effort the model should put into its response. Higher effort levels may result in more thorough analysis but take longer.
35393511
3512 Valid values are `low`, `medium`, `high`, `xhigh`, or `max`.
3513
35403514 - `"low"`
35413515
35423516 - `"medium"`
from line 3533
35593533
35603534- `compaction: optional BetaCompactionConfig or null`
35613535
3562 Compact the whole conversation and return a signed `compaction` block,
3563 alone, that a later request sends back first in `messages`, in place of
3564 the messages it summarizes. There is no trigger and no pause flag: sending
3565 the parameter compacts, and nothing is sampled after the block.
3536 Compaction configuration.
35663537
3567 The summarization prompt is the server's own unless `instructions` are
3568 given, which then replace it for this request; a value that is empty or
3569 only whitespace counts as absent.
3538 When set on `POST /v1/messages`, the request is a compaction request: the conversation in `messages` is summarized and the response holds only the resulting `compaction` block (`stop_reason` `"compaction"`), which later requests send first in `messages` in place of the messages it summarizes. `POST /v1/messages/count_tokens` accepts this parameter and ignores it: the count it returns is for the conversation in `messages` as sent. Cannot be combined with `context_management`.
35703539
35713540 - `type: "summarize"`
35723541
from line 3575
36063575
36073576 Skill ID
36083577
3609 maxLength: 64, minLength: 1
3578 minLength: 1, maxLength: 64
36103579
36113580 - `version: optional string`
36123581
36133582 Skill version or 'latest' for most recent version
36143583
3615 maxLength: 64, minLength: 1
3584 minLength: 1, maxLength: 64
36163585
36173586 - `string`
36183587
from line 3595
36263595
36273596 List of context management edits to apply
36283597
3629 minItems: 0
3630
36313598 - `BetaClearToolUses20250919Edit object`
36323599
36333600 - `type: "clear_tool_uses_20250919"`
from line 3693
37263693
37273694- `diagnostics: optional BetaDiagnosticsParam or null`
37283695
3729 Request-level diagnostics. Currently carries the previous response
3730 id for prompt-cache divergence reporting.
3696 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.
37313697
37323698 - `previous_message_id: optional string or null`
37333699
from line 3740
37743740
37753741 The opaque `fallback_credit_token` from a prior refusal's `stop_details` — the same string the bare-string form carries.
37763742
3777 maxLength: 2048, minLength: 1
3743 minLength: 1, maxLength: 2048
37783744
37793745 - `mode: optional "strict" or "best_effort"`
37803746
from line 3768
38023768
38033769 - `effort: optional "low" or "medium" or "high" or 2 more or null`
38043770
3805 All possible effort levels.
3771 How much effort the model should put into its response. Higher effort levels may result in more thorough analysis but take longer.
38063772
3773 Valid values are `low`, `medium`, `high`, `xhigh`, or `max`.
3774
38073775 - `"low"`
38083776
38093777 - `"medium"`
from line 3794
38263794
38273795 - `task_budget: optional BetaTokenTaskBudget or null`
38283796
3829 User-configurable total token budget across contexts.
3797 Configuration for token budget tracking across contexts.
38303798
38313799 - `type: "tokens"`
38323800
from line 3838
38703838
38713839 - `block_binding: optional BetaThinkingBlockBinding or null`
38723840
3873 Controls for block binding: what happens when a thinking block this
3874 request sends back fails the conversation check. Every field is optional;
3875 an empty object means every default.
3841 Controls for block binding: what happens when a thinking block this request sends back fails the conversation check. `null`, absent or an empty object means every default.
38763842
38773843 - `prefix_mismatch_behavior: optional BetaThinkingPrefixMismatchBehavior or null`
38783844
3879 What happens when a thinking block in `messages` fails the conversation
3880 check: it was created in a different conversation, or the messages before
3881 it have changed since. `"error"` (the default) fails the request with a
3882 400 error. `"drop_block"` removes the failing blocks and the request
3883 proceeds; the model no longer sees the dropped reasoning.
3845 "error" (default) | "drop_block". What happens when a thinking block in `messages` fails the conversation check (it was created in a different conversation, or the messages before it have changed since). "error" fails the request with a 400 error. "drop_block" removes the failing blocks and the request proceeds; each removal is reported in `input_transformations`.
38843846
38853847 - `"error"`
38863848
from line 3868
39063868
39073869 - `block_binding: optional BetaThinkingBlockBinding or null`
39083870
3909 Controls for block binding: what happens when a thinking block this
3910 request sends back fails the conversation check. Every field is optional;
3911 an empty object means every default.
3871 Controls for block binding: what happens when a thinking block this request sends back fails the conversation check. `null`, absent or an empty object means every default.
39123872
39133873 - `display: optional "summarized" or "omitted" or "updates" or null`
39143874
from line 3934
39743934
39753935- `speed: optional "standard" or "fast" or null`
39763936
3977 Inference speed mode. `fast` provides significantly faster output token generation at premium pricing. Not all models support `fast`; invalid combinations are rejected at create time.
3937 The inference speed mode for this request. `"fast"` enables high output-tokens-per-second inference.
39783938
39793939 - `"standard"`
39803940
from line 4203
42434203
42444204 Note that even with `temperature` of `0.0`, the results will not be fully deterministic.
42454205
4246 maximum: 1, minimum: 0
4206 minimum: 0, maximum: 1
42474207
42484208- `top_k: optional number`
42494209
from line 4227
42674227
42684228 Recommended for advanced use cases only.
42694229
4270 maximum: 1, minimum: 0
4230 minimum: 0, maximum: 1
42714231
42724232### Returns
42734233
from line 4249
42894249
42904250 - `container: BetaContainer or null`
42914251
4292 Information about the container used in the request (for the code execution tool)
4252 Information about the container used in this request.
42934253
4254 This will be non-null if a container tool (e.g. code execution) was used.
4255
42944256 - `id: string`
42954257
42964258 Identifier for the container used in this request
from line 4279
43174279
43184280 Skill ID
43194281
4320 maxLength: 64, minLength: 1
4282 minLength: 1, maxLength: 64
43214283
43224284 - `version: string`
43234285
43244286 The resolved version: a skill version ID for custom skills.
43254287
4326 maxLength: 64, minLength: 1
4288 minLength: 1, maxLength: 64
43274289
43284290 - `content: array of BetaContentBlock`
43294291
from line 4458
44964458
44974459 - `text: string`
44984460
4499 minLength: 0
4500
45014461 - `BetaThinkingBlock object`
45024462
45034463 - `type: "thinking"`
from line 4536
45764536
45774537 For a toolset member tool_use, the toolset family.
45784538
4579 maxLength: 64, minLength: 1, pattern: ^[a-zA-Z0-9_-]+$
4539 minLength: 1, maxLength: 64, pattern: ^[a-zA-Z0-9_-]+$
45804540
45814541 - `BetaServerToolUseBlock object`
45824542
from line 5040
50805040
50815041 - `tool_name: string`
50825042
5083 maxLength: 256, minLength: 1, pattern: ^[a-zA-Z0-9_-]{1,256}$
5043 minLength: 1, maxLength: 256, pattern: ^[a-zA-Z0-9_-]{1,256}$
50845044
50855045 - `tool_use_id: string`
50865046
from line 5090
51305090
51315091 - `text: string`
51325092
5133 minLength: 0
5134
51355093 - `is_error: boolean`
51365094
51375095 default: false
from line 5227
52695227
52705228 This is how the tool will be called by the model and in `tool_use` blocks.
52715229
5272 maxLength: 128, minLength: 1, pattern: ^[a-zA-Z0-9_-]{1,128}$
5230 minLength: 1, maxLength: 128, pattern: ^[a-zA-Z0-9_-]{1,128}$
52735231
52745232 - `allowed_callers: optional array of "direct" or "code_execution_20250825" or "code_execution_20260120" or "code_execution_20260521"`
52755233
from line 5491
55335491
55345492 - `configs: optional BetaBrowserToolsetConfigs or null`
55355493
5536 Per-member configuration for `browser_toolset_20260801`: one
5537 optional field per member tool, keyed by the member name — the same
5538 name the member's `tool_use` blocks carry. Every member is an
5539 accepted key, and a member's defaults apply wherever its key is
5540 absent. Unknown keys are rejected: the field set is this toolset
5541 version's complete member set.
5494 Sparse per-member overrides, keyed by member name. Absent, null, and {} are equivalent; a member's defaults apply wherever its key is absent.
55425495
55435496 - `type: optional BetaBrowserTypeConfig or null`
55445497
from line 6112
61596112
61606113 - `configs: optional BetaComputerToolsetConfigs or null`
61616114
6162 Per-member configuration for `computer_toolset_20260801`: one
6163 optional field per member tool, keyed by the member name — the same
6164 name the member's `tool_use` blocks carry. Every member is an
6165 accepted key, and a member's defaults apply wherever its key is
6166 absent. Unknown keys are rejected: the field set is this toolset
6167 version's complete member set.
6115 Sparse per-member overrides, keyed by member name. Absent, null, and {} are equivalent; a member's defaults apply wherever its key is absent.
61686116
61696117 - `type: optional BetaComputerTypeConfig or null`
61706118
from line 6466
65186466
65196467 Maximum number of times the tool can be used in the API request.
65206468
6521 exclusiveMinimum: 0
6469 minimum: 1
65226470
65236471 - `strict: optional boolean`
65246472
from line 6482
65346482
65356483 The city of the user.
65366484
6537 maxLength: 255, minLength: 1
6485 minLength: 1, maxLength: 255
65386486
65396487 - `country: optional string or null`
65406488
65416489 The two letter [ISO country code](https://en.wikipedia.org/wiki/ISO_3166-1_alpha-2) of the user.
65426490
6543 maxLength: 2, minLength: 2
6491 minLength: 2, maxLength: 2
65446492
65456493 - `region: optional string or null`
65466494
65476495 The region of the user.
65486496
6549 maxLength: 255, minLength: 1
6497 minLength: 1, maxLength: 255
65506498
65516499 - `timezone: optional string or null`
65526500
65536501 The [IANA timezone](https://nodatime.org/TimeZones) of the user.
65546502
6555 maxLength: 255, minLength: 1
6503 minLength: 1, maxLength: 255
65566504
65576505 - `BetaWebFetchTool20250910 object`
65586506
from line 6548
66006548
66016549 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.
66026550
6603 exclusiveMinimum: 0
6551 minimum: 1
66046552
66056553 - `max_uses: optional number or null`
66066554
66076555 Maximum number of times the tool can be used in the API request.
66086556
6609 exclusiveMinimum: 0
6557 minimum: 1
66106558
66116559 - `strict: optional boolean`
66126560
from line 6562
66146562
66156563 - `url_sources: optional BetaWebFetchURLSources or null`
66166564
6617 Which sources contribute to the set of URLs web fetch may fetch.
6565 Which sources contribute to the set of URLs the tool may fetch. Omitted means every source.
66186566
6619 Each key is a tagged variant: `user_input` is `all` or `none`; the
6620 two tool filters are `all`, `none`, `only` (only the named tools'
6621 results) or `except` (every result but the named tools'). A named tool
6622 must be declared in this request's `tools[]`.
6623
66246567 - `client_tool_results: optional BetaWebFetchURLSourceAll or BetaWebFetchURLSourceNone or BetaWebFetchURLSourceOnly or BetaWebFetchURLSourceExcept`
66256568
66266569 Which client tools' results contribute fetchable URLs: "all", "none", or an only or except list of client tool names from tools[].
from line 6686
67436686
67446687 Maximum number of times the tool can be used in the API request.
67456688
6746 exclusiveMinimum: 0
6689 minimum: 1
67476690
67486691 - `strict: optional boolean`
67496692
from line 6740
67976740
67986741 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.
67996742
6800 exclusiveMinimum: 0
6743 minimum: 1
68016744
68026745 - `max_uses: optional number or null`
68036746
68046747 Maximum number of times the tool can be used in the API request.
68056748
6806 exclusiveMinimum: 0
6749 minimum: 1
68076750
68086751 - `strict: optional boolean`
68096752
from line 6754
68116754
68126755 - `url_sources: optional BetaWebFetchURLSources or null`
68136756
6814 Which sources contribute to the set of URLs web fetch may fetch.
6757 Which sources contribute to the set of URLs the tool may fetch. Omitted means every source.
68156758
6816 Each key is a tagged variant: `user_input` is `all` or `none`; the
6817 two tool filters are `all`, `none`, `only` (only the named tools'
6818 results) or `except` (every result but the named tools'). A named tool
6819 must be declared in this request's `tools[]`.
6820
68216759 - `BetaWebFetchTool20260309 object`
68226760
68236761 Web fetch tool with use_cache parameter for bypassing cached content.
from line 6802
68646802
68656803 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.
68666804
6867 exclusiveMinimum: 0
6805 minimum: 1
68686806
68696807 - `max_uses: optional number or null`
68706808
68716809 Maximum number of times the tool can be used in the API request.
68726810
6873 exclusiveMinimum: 0
6811 minimum: 1
68746812
68756813 - `strict: optional boolean`
68766814
from line 6816
68786816
68796817 - `url_sources: optional BetaWebFetchURLSources or null`
68806818
6881 Which sources contribute to the set of URLs web fetch may fetch.
6819 Which sources contribute to the set of URLs the tool may fetch. Omitted means every source.
68826820
6883 Each key is a tagged variant: `user_input` is `all` or `none`; the
6884 two tool filters are `all`, `none`, `only` (only the named tools'
6885 results) or `except` (every result but the named tools'). A named tool
6886 must be declared in this request's `tools[]`.
6887
68886821 - `use_cache: optional boolean`
68896822
68906823 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 6862
69296862
69306863 Maximum number of times the tool can be used in the API request.
69316864
6932 exclusiveMinimum: 0
6865 minimum: 1
69336866
69346867 - `response_inclusion: optional "full" or "excluded"`
69356868
from line 6924
69916924
69926925 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.
69936926
6994 exclusiveMinimum: 0
6927 minimum: 1
69956928
69966929 - `max_uses: optional number or null`
69976930
69986931 Maximum number of times the tool can be used in the API request.
69996932
7000 exclusiveMinimum: 0
6933 minimum: 1
70016934
70026935 - `response_inclusion: optional "full" or "excluded"`
70036936
from line 6946
70136946
70146947 - `url_sources: optional BetaWebFetchURLSources or null`
70156948
7016 Which sources contribute to the set of URLs web fetch may fetch.
6949 Which sources contribute to the set of URLs the tool may fetch. Omitted means every source.
70176950
7018 Each key is a tagged variant: `user_input` is `all` or `none`; the
7019 two tool filters are `all`, `none`, `only` (only the named tools'
7020 results) or `except` (every result but the named tools'). A named tool
7021 must be declared in this request's `tools[]`.
7022
70236951 - `use_cache: optional boolean`
70246952
70256953 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 6962
70346962
70356963 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
70366964
6965 - `string`
6966
70376967 - `"claude-fable-5-1" or "claude-opus-5-5" or "claude-mythos-5-1" or 15 more`
70386968
70396969 The model that will complete your prompt.
from line 7006
70767006
70777007 Powerful intelligence for long-running agents and coding
70787008
7079 - `"claude-mythos-preview"`
7080
7081 New class of intelligence, strongest in coding and cybersecurity
7082
70837009 - `"claude-opus-4-6"`
70847010
70857011 Powerful intelligence for long-running agents and coding
from line 7038
71127038
71137039 High-performance model for agents and coding
71147040
7115 - `string`
7041 - `"claude-mythos-preview"`
71167042
7043 **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.
7044
7045 New class of intelligence, strongest in coding and cybersecurity
7046
71177047 - `name: "advisor"`
71187048
71197049 Name of the tool.
from line 7082
71527082
71537083 Maximum number of times the tool can be used in the API request.
71547084
7155 exclusiveMinimum: 0
7085 minimum: 1
71567086
71577087 - `strict: optional boolean`
71587088
from line 7118
71887118
71897119 - `defer_loading: optional boolean`
71907120
7191
7121 If true, tool will not be included in initial system prompt. Only loaded when returned via tool_reference from tool search.
7122
7123 - `strict: optional boolean`
7124
7125 When true, guarantees schema validation on tool names and inputs
7126
7127 - `BetaToolSearchToolRegex20251119 object`
7128
7129 - `type: "tool_search_tool_regex_20251119" or "tool_search_tool_regex"`
7130
7131 - `"tool_search_tool_regex_20251119"`
7132
7133 - `"tool_search_tool_regex"`
7134
7135 - `name: "tool_search_tool_regex"`
7136
7137 Name of the tool.
7138
7139 This is how the tool will be called by the model and in `tool_use` blocks.
7140
7141 - `allowed_callers: optional array of "direct" or "code_execution_20250825" or "code_execution_20260120" or "code_execution_20260521"`
7142
7143 - `"direct"`
7144
7145 - `"code_execution_20250825"`
7146
7147 - `"code_execution_20260120"`
7148
7149 - `"code_execution_20260521"`
7150
7151 - `cache_control: optional BetaCacheControlEphemeral or null`
7152
7153 Create a cache control breakpoint at this content block.
7154
7155 - `defer_loading: optional boolean`
7156
7157 If true, tool will not be included in initial system prompt. Only loaded when returned via tool_reference from tool search.
7158
7159 - `strict: optional boolean`
7160
7161 When true, guarantees schema validation on tool names and inputs
7162
7163 - `BetaMCPToolset object`
7164
7165 Configuration for a group of tools from an MCP server.
7166
7167 Allows configuring enabled status and defer_loading for all tools
7168 from an MCP server, with optional per-tool overrides.
7169
7170 - `type: "mcp_toolset"`
7171
7172 - `mcp_server_name: string`
7173
7174 Name of the MCP server to configure tools for
7175
7176 minLength: 1, maxLength: 255
7177
7178 - `cache_control: optional BetaCacheControlEphemeral or null`
7179
7180 Create a cache control breakpoint at this content block.
7181
7182 - `configs: optional map[BetaMCPToolConfig] or null`
7183
7184 Configuration overrides for specific tools, keyed by tool name
7185
7186 - `defer_loading: optional boolean`
7187
7188 - `enabled: optional boolean`
7189
7190 - `default_config: optional BetaMCPToolDefaultConfig`
7191
7192 Default configuration applied to all tools from this server
7193
7194 - `defer_loading: optional boolean`
7195
7196 - `enabled: optional boolean`
7197
7198 - `tools: optional array of BetaMCPToolParam or null`
7199
7200 The server's tool listing, pinned: when present, the server is not asked for its tools before sampling and exactly these entries, with `default_config` and `configs` applied, are the toolset's tools. Copy it from the `mcp_tool_listing` block of an earlier response.
7201
7202 - `input_schema: map[unknown]`
7203
7204 The tool's input schema as the MCP server lists it, verbatim.
7205
7206 - `name: s
No line in this hunk matches that.