fix: change model mismatch logs from WARNING to DEBUG

[milan-berri]

PR #19943 added logging when the proxy overrides model names to prevent internal provider prefixes from leaking to clients. The behavior works correctly but logs a WARNING on every request with model mismatch.

For high-traffic customers using model aliases or provider prefixes, this creates millions of warnings per day, flooding logs and causing disk space issues.

Changed log level from WARNING to DEBUG since:

• The model mismatch is expected behavior when using aliases
• The override happens correctly regardless of log level
• Operators can still enable with LITELLM_LOG=DEBUG for debugging

Relevant issues

Fixes #20990

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Type

🐛 Bug Fix

Changes

• common_request_processing.py: 2 warnings -> debug (non-streaming)
• proxy_server.py: 1 warning -> debug (streaming)

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Project	Deployment	Actions	Updated (UTC)
litellm	Ready	Preview, Comment	Feb 11, 2026 9:45pm

[greptile-apps]

Greptile Overview

Greptile Summary

Downgrades 3 model-mismatch log messages from WARNING to DEBUG across the non-streaming (common_request_processing.py) and streaming (proxy_server.py) response paths. The model override behavior is unchanged — only the log level is reduced. This prevents log flooding for high-traffic deployments that use model aliases or provider prefixes, where mismatches are expected.

• common_request_processing.py: 2 WARNING → DEBUG (dict and object response branches)
• proxy_server.py: 1 WARNING → DEBUG (streaming chunk branch)
• Minor: a comment in proxy_server.py still references "This warning" — should say "This debug log"

Confidence Score: 5/5

• This PR is safe to merge — it only changes log levels with no behavioral impact.
• The change is minimal (3 lines), purely cosmetic (log level only), and the override logic is completely untouched. No new code paths, no new dependencies, no risk of regression.
• No files require special attention.

Important Files Changed

Filename	Overview
litellm/proxy/common_request_processing.py	Two verbose_proxy_logger.warning() calls changed to .debug() for model mismatch override messages. No behavioral change.
litellm/proxy/proxy_server.py	One verbose_proxy_logger.warning() changed to .debug() for streaming chunk model mismatch. Stale comment still references "warning".

[greptile-apps]

_{2 files reviewed, 1 comment}

_{Edit Code Review Agent Settings | Greptile}

[greptile-apps]

Additional Comments (1)

litellm/proxy/proxy_server.py
Stale comment — still says "This warning is intentionally verbose" but the log is now DEBUG level.

    # Note: This debug log is intentionally verbose. A mismatch is a useful signal that an