LiteLLM Proxy Cost Override Ignored in Upstream Proxy Chaining

What this error means

model_info cost override (input_cost_per_token/output_cost_per_token) ignored when using litellm_proxy/ prefix is a LiteLLM failure pattern reported for developers trying to fix litellm model_info cost_per_token override being ignored when calling upstream litellm proxy. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

GitHub issue 27656 (2026-05-11) reports that when a LiteLLM proxy (Y) calls another LiteLLM proxy (X) using litellm_proxy/ model prefix, cost overrides in model_info (input_cost_per_token, output_cost_per_token) are completely ignored. Upstream proxy costs are always used, breaking cost tracking for multi-layer proxy deployments.

Common causes

• When chaining LiteLLM proxy instances (Y calls X via litellm_proxy/ prefix), setting input_cost_per_token: 0 or output_cost_per_token: 0 in model_info has no effect. The upstream proxy’s costs are always used instead. This breaks cost tracking accuracy for organizations running multi-layer LiteLLM proxy setups, making budget monitoring unreliable.
• GitHub issue 27656 (2026-05-11) reports that when a LiteLLM proxy (Y) calls another LiteLLM proxy (X) using litellm_proxy/ model prefix, cost overrides in model_info (input_cost_per_token, output_cost_per_token) are completely ignored. Upstream proxy costs are always used, breaking cost tracking for multi-layer proxy deployments.

Quick fixes

1. Confirm the exact error signature matches model_info cost override (input_cost_per_token/output_cost_per_token) ignored when using litellm_proxy/ prefix.
2. Check the LiteLLM account, local tool state, and provider configuration involved in the failing workflow.
3. Compare the failing environment with a known working setup, then change one configuration value at a time.

Platform/tool-specific checks

• Verify the command, editor, extension, or API client that produced the error.
• Compare local settings with CI, deployment, or editor-level settings when the error appears in only one environment.
• Avoid deleting credentials, local model data, or project settings until the failing scope is clear.

Step-by-step troubleshooting

1. Capture the exact error message and the command, editor action, or request that triggered it.
2. Check whether the failure is account/auth, quota/rate, model/provider, local runtime, or deployment configuration.
3. Review the source evidence below and compare it with your environment.
4. Apply one change at a time and rerun the smallest failing action.
5. Keep the working fix documented for the team or deployment environment.

How to prevent it

• Keep provider/tool configuration documented.
• Record non-secret diagnostics such as tool version, provider name, model name, and command path.
• Add a lightweight check before CI or production workflows depend on the tool.

Sources checked

• https://github.com/BerriAI/litellm/issues/27656

Evidence note: GitHub issue 27656 (2026-05-11) reports that when a LiteLLM proxy (Y) calls another LiteLLM proxy (X) using litellm_proxy/ model prefix, cost overrides in model_info (input_cost_per_token, output_cost_per_token) are completely ignored. Upstream proxy costs are always used, breaking cost tracking for multi-layer proxy deployments.

Related errors

• LiteLLM cost tracking inaccurate with model routing
• LiteLLM proxy chain double-counts token costs
• LiteLLM custom model pricing not applied to routed requests

FAQ

What should I check first?

Start with the exact model_info cost override (input_cost_per_token/output_cost_per_token) ignored when using litellm_proxy/ prefix text and the smallest action that reproduces it.

Can I ignore this error?

No. Treat it as a failed LiteLLM workflow until the root cause is understood.

Is this guaranteed to have one fix?

No. The imported evidence supports the troubleshooting path above, but tool behavior can vary by account, plan, version, provider, and local configuration.

How do I know the fix worked?

Rerun the same command, editor action, or request. The fix is working when that action completes without model_info cost override (input_cost_per_token/output_cost_per_token) ignored when using litellm_proxy/ prefix.