Lowering AWS bedrock context window?

[icsy7867]

I'm having some issues, and I'm not sure if I understood the docs correctly.

I am connecting to claude sonnet via AWS bedrock. I'm wanting to lower the context window, or at least the input window via max_input_tokens.

However i have a test chat going that is going way beyond that window. Reading more I also enabled the enable pre check boolean.

Im using litellm as a proxy. And I'm running v1.81.0

Thank you.!!

[icsy7867]

Posted in discord as well. I've tried the converse and bedrock prefixes.

• model_name: Claude-Sonnet-Test
  litellm_params:
  model: bedrock/us-gov.anthropic.claude-sonnet-4-5-20250929-v1:0
  api_base: https://bedrock-runtime-fips.us-gov-east-1.amazonaws.com
  aws_access_key_id: os.environ/AWS_SECRET_BEDROCK_ID
  aws_secret_access_key: os.environ/AWS_SECRET_BEDROCK_KEY
  aws_region_name: us-gov-east-1
  drop_params: true
  model_info:
  input_cost_per_token: 0.0000035
  output_cost_per_token: 0.000018
  max_input_tokens: 1000

Maybe because its in govcloud?

[icsy7867]

Appears to have been this issue:
fix(bedrock): respect api_base and aws_bedrock_runtime_endpoint in count_tokens endpoint by @stias in #24199 ?

I upgrade to 1.82.x and things started to work.