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xAI grok-4-latest model retirement

Stopped workingSubscribe to xAIShare

Calls to the model grok-4-latest on xAI stopped working on May 15, 2026.


The error you get

What xAI answers a call to grok-4-latest once the model is gone, as recorded from real responses:

HTTP 400
{"code":"invalid-argument","error":"Model not found: grok-4-latest"}

What to use instead of grok-4-latest

Move to grok-4.3. Maps to grok-4.3 with reasoning effort "low". Grok 4 had no non-reasoning mode at all, so this is the first time the workload can be run without thinking tokens if you want that.


Facts

API
xAI api.x.ai
Model
grok-4-latest
Kind
Model retirement
Takes effect
May 15, 2026
Calls after that day
Fail
Source
models.dev
Last updated
Verified
, against xAI's own pages

Questions

When does grok-4-latest shut down?

Calls to the model grok-4-latest on xAI stopped working on May 15, 2026.

What happens to calls after May 15, 2026?

They have failed since May 15, 2026.

What error does grok-4-latest return once it is shut down?

xAI answers HTTP 400: "Model not found: grok-4-latest". Send another model to fix it.

How do I find the calls this hits in my code?

Okapi reads your repository, finds the calls this change hits and opens a pull request with the fix. It never commits to your branches: every change comes as a pull request you review.


More from xAI 10

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  2. grok-4Model retirement Stopped working
  3. grok-4-0709Model retirement Redirected
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  5. grok-4-1-fast-reasoningModel retirement Redirected
  6. grok-4-fast-non-reasoningModel retirement Redirected
  7. grok-4-fast-reasoningModel retirement Redirected
  8. grok-code-fast-1Model retirement Redirected
  9. grok-imagine-image-proModel retirement Redirected
  10. grok-2Model retirement Stopped working

You fixed this one by hand.

Okapi opens the pull request with the fix before the next breaking change reaches your code.

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