MS Foundry + Kimi Code 2.7 - 400 Unrecognized request argument supplied: prompt_cache_key

What version of Kimi Code is running?

0.32.0

Which open platform/subscription were you using?

.

Which model were you using?

kimi-k2.7-code

What platform is your computer?

Linux 5.15.167.4-microsoft-standard-WSL2 x86_64 x86_64

What issue are you seeing?

Kimi Code CLI sends prompt_cache_key in a request to an OpenAI-compatible endpoint, and the endpoint rejects it with HTTP 400: Unrecognized request argument supplied: prompt_cache_key.

Config (redacted)

default_model = "azure/kimi-k2.7-code"

[providers.azure-foundry]
type = "openai"
base_url = "https://<redacted>/openai/v1"
api_key = "<redacted>"

[providers.azure-foundry.custom_headers]
api-key = "<redacted>"

[models."azure/kimi-k2.7-code"]
provider = "azure-foundry"
model = "Kimi-K2.7-Code"
max_context_size = 262144
capabilities = [ "thinking", "tool_use", "image_in" ]
reasoning_key = "reasoning_content"

[thinking]
enabled = false



### What steps can reproduce the bug?

### Steps to reproduce

1. Configure provider/model as above.
2. Start a session (simple prompt like test).
3. First LLM turn fails.

### What is the expected behavior?

_No response_

### Additional information

_No response_

Start by tracing how the Kimi Code CLI builds the first request for the configured OpenAI-compatible provider and where prompt_cache_key is added. Reproduce the failure with the supplied Azure Foundry configuration, then verify that the session starts successfully without sending an argument the endpoint rejects.