Where does the bug appear (feature/product)?
Cursor IDE
Describe the Bug
Attempting to use Claude Fable 5 through AWS Bedrock (Access Key) with model ID: global.anthropic.claude-fable-5.
When attempting to submit a request, the Cursor attempts to submit a request, but returns this response after 10 attempts:
Error:
Request ID: 2bf782ca-8beb-46d9-9a95-6d168f45c5e4
{"error":"ERROR_OPENAI","details":{"title":"Unable to reach the model provider","detail":"We encountered an issue when using your API key: Provider was unable to process your request\n\nAPI Error:\n\n```\n10 validation errors detected: Value null at 'toolConfig.tools.1.member.toolSpec.name' failed to satisfy constraint: Member must not be null; Value null at 'toolConfig.tools.2.member.toolSpec.name' failed to satisfy constraint: Member must not be null; Value null at 'toolConfig.tools.3.member.toolSpec.name' failed to satisfy constraint: Member must not be null; Value null at 'toolConfig.tools.4.member.toolSpec.name' failed to satisfy constraint: Member must not be null; Value null at 'toolConfig.tools.5.member.toolSpec.name' failed to satisfy constraint: Member must not be null; Value null at 'toolConfig.tools.6.member.toolSpec.name' failed to satisfy constraint: Member must not be null; Value null at 'toolConfig.tools.7.member.toolSpec.name' failed to satisfy constraint: Member must not be null; Value null at 'toolConfig.tools.8.member.toolSpec.name' failed to satisfy constraint: Member must not be null; Value null at 'toolConfig.tools.9.member.toolSpec.name' failed to satisfy constraint: Member must not be null; Value null at 'toolConfig.tools.10.member.toolSpec.name' failed to satisfy constraint: Member must not be null\n```","additionalInfo":{},"buttons":[],"planChoices":[]},"isExpected":true}
Steps to Reproduce
- Enable AWS Bedrock in Models (Set Access Key ID, Secret Access Key, Region)
- Add
global.anthropic.claude-fable-5custom model ID. - Run an agent with selected model
global.anthropic.claude-fable-5.
Expected Behavior
It works as expected with Claude Sonnet and Opus, tested with model ID: global.anthropic.claude-opus-4-8.
Operating System
MacOS
Version Information
Version: 3.7.21
VS Code Extension API: 1.105.1
Commit: 517f696d8ab6c53eb04fbfdaae705cd146bf3460
Date: 2026-06-07T21:46:09.237Z
Layout: editor
Build Type: Stable
Release Track: Default
Electron: 39.8.1
Chromium: 142.0.7444.265
Node.js: 22.22.1
V8: 14.2.231.22-electron.0
xterm.js: 6.1.0-beta.256
OS: Darwin arm64 25.3.0
Does this stop you from using Cursor
No - Cursor works, but with this issue