AWS Bedrock model - ERROR_BAD_MODEL_NAME

[dido (Deyan Slavov)]

Where does the bug appear (feature/product)?

Cursor IDE

Describe the Bug

When run a prompt with Anthropic model provided via AWS Bedrock throws error

ERROR_BAD_MODEL_NAME
AI Model Not Found
Model name is not valid: \"us.anthropic.claude-opus-4-5-20251101-v1:0

Steps to Reproduce

Add AWS Bedrock models from Anthropic family and prompt it.

Screenshots / Screen Recordings

Operating System

MacOS

Current Cursor Version (Menu → About Cursor → Copy)

Version: 2.4.0-pre.35.patch.0 (Universal)
VSCode Version: 1.105.1
Commit: cd27035e3d5f14f5bece2ba854fddf0368f6c1c0
Date: 2026-01-15T02:06:39.762Z
Build Type: Stable
Release Track: Early Access
Electron: 37.7.0
Chromium: 138.0.7204.251
Node.js: 22.20.0
V8: 13.8.258.32-electron.0
OS: Darwin arm64 25.2.0

For AI issues: which model did you use?

All Anthropic models from Claude family in AWS Bedrock

Additional Information

Bug appeared while using cursor last night. I am on Nightly channel updates.

Does this stop you from using Cursor

No - Cursor works, but with this issue

[dido (Deyan Slavov)]

Downgrading Cursor to 2.3.35 stable fixed the problem. I can confirm issue is present on the nightly version only.

[deanrie]

Hey, thanks for the detailed report and for testing on the stable version.

This is a regression in the Early Access build 2.4.0-pre.35. It’s a known issue with AWS Bedrock model validation. Good to hear that downgrading to 2.3.35 stable fixed it.

Until this is fixed in Early Access, please stay on the stable 2.3.35 version.