Sweep 19 Sep 2026 · 02:36Z Build v2.1.278 500 read Stable v2.1.267 Latest v2.1.278 Next v2.1.280 Feeds RSS JSON llms.txt Unofficial
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api/messages

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Lines+82added
Lines−130removed
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from line 1072
10721072 
10731073 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
10741074 
1075 - `"claude-sonnet-5" or "claude-fable-5" or "claude-mythos-5" or 12 more`
1075 - `"claude-fable-5-1" or "claude-mythos-5-1" or "claude-sonnet-5" or 14 more`
10761076 
10771077 The model that will complete your prompt.
10781078 
10791079 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
10801080 
1081 - `"claude-fable-5-1"`
1082 
1083 Frontier intelligence for ambitious tasks across coding, scientific discovery, and enterprise workflows
1084 
1085 - `"claude-mythos-5-1"`
1086 
1087 Our most capable model for cybersecurity and biology research, available through trusted access programs
1088 
10811089 - `"claude-sonnet-5"`
10821090 
10831091 High-performance model for coding and agents
from line 1675
16671675 
16681676 - `type: "browser_toolset_20260801"`
16691677 
1670 - `allowed_callers: optional array of "direct" or "code_execution_20250825" or "code_execution_20260120" or "code_execution_20260521"`
1671 
1672 - `"direct"`
1673 
1674 - `"code_execution_20250825"`
1675 
1676 - `"code_execution_20260120"`
1677 
1678 - `"code_execution_20260521"`
1679 
16801678 - `cache_control: optional CacheControlEphemeral or null`
16811679 
16821680 Create a cache control breakpoint at this content block.
from line 2107
21092107 
21102108 - `type: "computer_toolset_20260801"`
21112109 
2112 - `allowed_callers: optional array of "direct" or "code_execution_20250825" or "code_execution_20260120" or "code_execution_20260521"`
2113 
2114 - `"direct"`
2115 
2116 - `"code_execution_20250825"`
2117 
2118 - `"code_execution_20260120"`
2119 
2120 - `"code_execution_20260521"`
2121 
21222110 - `cache_control: optional CacheControlEphemeral or null`
21232111 
21242112 Create a cache control breakpoint at this content block.
from line 3745
37573745 
37583746 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
37593747 
3760 - `"claude-sonnet-5" or "claude-fable-5" or "claude-mythos-5" or 12 more`
3748 - `"claude-fable-5-1" or "claude-mythos-5-1" or "claude-sonnet-5" or 14 more`
37613749 
37623750 The model that will complete your prompt.
37633751 
37643752 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
37653753 
3754 - `"claude-fable-5-1"`
3755 
3756 Frontier intelligence for ambitious tasks across coding, scientific discovery, and enterprise workflows
3757 
3758 - `"claude-mythos-5-1"`
3759 
3760 Our most capable model for cybersecurity and biology research, available through trusted access programs
3761 
37663762 - `"claude-sonnet-5"`
37673763 
37683764 High-performance model for coding and agents
from line 5381
53855381 
53865382 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
53875383 
5388 - `"claude-sonnet-5" or "claude-fable-5" or "claude-mythos-5" or 12 more`
5384 - `"claude-fable-5-1" or "claude-mythos-5-1" or "claude-sonnet-5" or 14 more`
53895385 
53905386 The model that will complete your prompt.
53915387 
53925388 See [models](https://docs.anthropic.com/en/docs/models-overview) for additional details and options.
53935389 
5390 - `"claude-fable-5-1"`
5391 
5392 Frontier intelligence for ambitious tasks across coding, scientific discovery, and enterprise workflows
5393 
5394 - `"claude-mythos-5-1"`
5395 
5396 Our most capable model for cybersecurity and biology research, available through trusted access programs
5397 
53945398 - `"claude-sonnet-5"`
53955399 
53965400 High-performance model for coding and agents
from line 5904
59005904 
59015905 - `type: "browser_toolset_20260801"`
59025906 
5903 - `allowed_callers: optional array of "direct" or "code_execution_20250825" or "code_execution_20260120" or "code_execution_20260521"`
5904 
5905 - `"direct"`
5906 
5907 - `"code_execution_20250825"`
5908 
5909 - `"code_execution_20260120"`
5910 
5911 - `"code_execution_20260521"`
5912 
59135907 - `cache_control: optional CacheControlEphemeral or null`
59145908 
59155909 Create a cache control breakpoint at this content block.
from line 6336
63426336 
63436337 - `type: "computer_toolset_20260801"`
63446338 
6345 - `allowed_callers: optional array of "direct" or "code_execution_20250825" or "code_execution_20260120" or "code_execution_20260521"`
6346 
6347 - `"direct"`
6348 
6349 - `"code_execution_20250825"`
6350 
6351 - `"code_execution_20260120"`
6352 
6353 - `"code_execution_20260521"`
6354 
63556339 - `cache_control: optional CacheControlEphemeral or null`
63566340 
63576341 Create a cache control breakpoint at this content block.
from line 8270
82868270 
82878271 - `type: "browser_toolset_20260801"`
82888272 
8289 - `allowed_callers: optional array of "direct" or "code_execution_20250825" or "code_execution_20260120" or "code_execution_20260521"`
8290 
8291 - `"direct"`
8292 
8293 - `"code_execution_20250825"`
8294 
8295 - `"code_execution_20260120"`
8296 
8297 - `"code_execution_20260521"`
8298 
82998273 - `cache_control: optional CacheControlEphemeral or null`
83008274 
83018275 Create a cache control breakpoint at this content block.
from line 8418
84448418 
84458419 - `enabled: optional boolean or null`
84468420 
8447 Whether this member is offered to the model. Default i
8421 Whether this member is offered to the model. Default is per member, per the toolset's documentation. A member whose enabled resolves false is withheld from the served schema.
8422 
8423 - `left_click: optional BrowserLeftClickConfig or null`
8424 
8425 `left_click`'s config overrides.
8426 
8427 - `defer_loading: optional boolean or null`
8428 
8429 Defer loading for this member. Must resolve to the same value on every enabled member of the toolset.
8430 
8431 - `enabled: optional boolean or null`
8432 
8433 Whether this member is offered to the model. De