Create a Message changedapi/messages/create
Nearest release: v2.1.301, published 11 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+20added
Lines−1removed
From line
1,273
where the diff opens
First seen
14 Aug 2026
this site's first read of the page
Recorded edits24to this page, all time
The whole hunk
from line 1273, old and new numbered
/
from line 1273
12731273
12741274 - `"standard_only"`
12751275
1276- `speed: optional "standard" or "fast" or null`
1277
1278 The inference speed mode for this request. `"fast"` enables high output-tokens-per-second inference.
1279
1280 Some models require the `fast-mode-2026-02-01` beta header for any `speed` value. See [fast mode](https://platform.claude.com/docs/en/build-with-claude/fast-mode?sdk_languages=http) for which models.
1281
1282 - `"standard"`
1283
1284 - `"fast"`
1285
12761286- `stop_sequences: optional array of string`
12771287
12781288 Custom text sequences that will cause the model to stop generating.
from line 4208
41984208
41994209 - `"batch"`
42004210
4211 - `speed: "standard" or "fast" or null`
4212
4213 The inference speed mode used for this request.
4214
4215 - `"standard"`
4216
4217 - `"fast"`
4218
42014219- `RawMessageStreamEvent = RawMessageStartEvent or RawMessageDeltaEvent or RawMessageStopEvent or 3 more`
42024220
42034221 - `RawMessageStartEvent object`
from line 4525
45074525 "web_fetch_requests": 2,
45084526 "web_search_requests": 0
45094527 },
4510 "service_tier": "standard"
4528 "service_tier": "standard",
4529 "speed": "standard"
45114530 }
45124531}
45134532```
No line in this hunk matches that.