AI Agent with Anthropic models fails: 'temperature and top_p cannot both be specified' error

[Richcantoo]

Bug Description

When using Anthropic Chat Model (Claude) in AI Agent node, the workflow fails with:

• Error: Bad request - please check your parameters
• Message: 'temperature' and 'top_p' cannot both be specified for this model

Root Cause
n8n sends both temperature and top_p parameters by default, but Anthropic's API requires only one to be set (as per their documentation: "You should either alter temperature or top_p, but not both").

To Reproduce

1. Add AI Agent node
2. Select Anthropic Chat Model
3. Choose any Claude model (tested with Claude Opus 4.1)
4. Run workflow
5. Error occurs regardless of parameter configuration

Expected Behavior

n8n should only send either temperature OR top_p to Anthropic's API, not both.

Environment

• n8n version: [your version]
• Deployment: [self-hosted/cloud]
• Node: AI Agent with Anthropic Chat Model

Workaround

Currently using HTTP Request node to directly call Anthropic API as the AI Agent node is unusable with Claude models.

To Reproduce

1. Add AI Agent node
2. Select Anthropic Chat Model
3. Choose any Claude model (tested with Claude Opus 4.1)
4. Run workflow
5. Error occurs regardless of parameter configuration

Expected behavior

n8n should only send either temperature OR top_p to Anthropic's API, not both.

Debug Info

n8n sends both temperature and top_p parameters by default, but Anthropic's API requires only one to be set (as per their documentation: "You should either alter temperature or top_p, but not both").

Operating System

macOS 13.7.7

n8n Version

1.106.3

Node.js Version

n8n Cloud

Database

SQLite (default)

Execution mode

main (default)

Hosting

n8n cloud

[Joffcom]

Hey @Richcantoo,

Thank you for reaching out! We’ve received your issue and are looking into it. To help us track this internally, we’ve created a Linear ticket with the reference: "GHC-3725".

We’ll keep you updated as we make progress, but if you have any additional details or context to share, feel free to add them here - it’s always helpful!

Thanks for your patience and for bringing this to our attention.

[ericmwhite]

I’m experiencing the same anytime I attempt to use the Anthropic node (agent or llm message)

[DevHays]

Same for me ....

[cbrooker]

Adding another confirmation to the list. I have the same error. If I manually specify these values or omit them, they are always being added to the request and Anthropic is rejecting it. Even if the values are -1 or empty string.

Version 1.107.3

[burivuhster]

Hey, thank you for the report! This was fixed just recently by this PR: #18213
It should work in 1.108.0 which is now in beta and will be available in stable release channel next Monday.

[Julian-Ayoub]

I appear to be having this same issue for Claude Sonnet 4.5, but not for Claude Sonnet 4:

No top_p set, sampling temperature set to 0.3:
top_p cannot be set to -1 for this model.

top_p set to 1.0 or 0 temperature set to 0.3
temperature and top_p cannot both be specified for this model. Please use only one.

top_p set to 0.9, sampling temperature not set:
temperature and top_p cannot both be specified for this model. Please use only one.

n8n Version
1.113.3

[simonedstrom96]

Same here, using AWS Bedrock Claude Sonnet 4.5

I appear to be having this same issue for Claude Sonnet 4.5, but not for Claude Sonnet 4:

No top_p set, sampling temperature set to 0.3: top_p cannot be set to -1 for this model.

top_p set to 1.0 or 0 temperature set to 0.3 temperature and top_p cannot both be specified for this model. Please use only one.

top_p set to 0.9, sampling temperature not set: temperature and top_p cannot both be specified for this model. Please use only one.

n8n Version 1.113.3

[mlaucis]

Same thing, no issue with Sonnet 4, but Sonnet 4.5 throws the top_p error.

v 1.113.3

[lukevr]

Same here

[mlaucis]

seems like its tracked here #20240