OpenRouter / AI Coding Tools

Pydantic AI thinking=False silently dropped for OpenRouter and other reasoning models

Fix Pydantic AI silently dropping thinking=False setting when routing through OpenRouter, xAI, or Bedrock reasoning models Includes evidence for OpenRouter troubleshooting demand.

Source-backed Last updated May 12, 2026 1 source Needs local verification

Category: AI Coding Tools
Error signature: model_settings thinking=False silently dropped — reasoning field missing from OpenRouter request body
Quick fix: Compare the failing environment with a known working setup, then change one configuration value at a time.
Updated: May 12, 2026
Verification status: Source-backed
Evidence: 1 public source URL

Before you change production

This page includes public source URLs in the imported troubleshooting record. Compare those references with your version and environment before applying changes.

Reproduce the smallest failing action and save non-secret logs before changing configuration.
Check versions for OpenRouter, related SDKs, package managers, CI runners, and hosting providers.
Change one setting or dependency at a time, then rerun the same failing command or request.
Avoid destructive commands, credential rotation, billing changes, or security relaxations without a rollback plan.

What this error means

model_settings thinking=False silently dropped — reasoning field missing from OpenRouter request body is a OpenRouter failure pattern reported for developers trying to fix pydantic ai silently dropping thinking=false setting when routing through openrouter, xai, or bedrock reasoning models. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

Pydantic AI issue #5379 (created 2026-05-12, 3 comments). thinking=False silently dropped for reasoning models routed through OpenRouterModel, xAI, Bedrock. HTTP body contains no reasoning field. No exception or warning thrown — completely silent failure.

Common causes

Pydantic AI developers set model_settings={'thinking': False} to disable reasoning mode, but the setting is silently dropped — no exception, no warning. The HTTP body sent to OpenRouter contains no reasoning field at all. Affects cost control and response behavior for paid API usage
Pydantic AI issue #5379 (created 2026-05-12, 3 comments). thinking=False silently dropped for reasoning models routed through OpenRouterModel, xAI, Bedrock. HTTP body contains no reasoning field. No exception or warning thrown — completely silent failure.

Quick fixes

Confirm the exact error signature matches model_settings thinking=False silently dropped — reasoning field missing from OpenRouter request body.
Check the OpenRouter account, local tool state, and provider configuration involved in the failing workflow.
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

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

Diagnostic flow for this page

Match model_settings thinking=False silently dropped — reasoning field missing from OpenRouter request body exactly before applying the quick fix.
Compare the failing environment with OpenRouter versions, account scope, provider settings, and deployment context.
Check the listed common causes in order, starting with the cause that best matches your logs.
Use the evidence status below to decide whether to confirm against public sources or official documentation.
Apply one reversible change, rerun the smallest failing action, and keep rollback notes.

FAQ

What does model_settings thinking=False silently dropped — reasoning field missing from OpenRouter request body mean in OpenRouter?

model_settings thinking=False silently dropped — reasoning field missing from OpenRouter request body indicates the workflow described by "Pydantic AI thinking=False silently dropped for OpenRouter and other reasoning models" failed in a AI Coding Tools context. Start by confirming the exact signature and the component that emitted it.

What should I check first for model_settings thinking=False silently dropped — reasoning field missing from OpenRouter request body?

Check whether this cause matches your environment: Pydantic AI developers set model_settings={'thinking': False} to disable reasoning mode, but the setting is silently dropped — no exception, no warning. The HTTP body sent to OpenRouter contains no reasoning field at all. Affects cost control and response behavior for paid API usage

Is the model_settings thinking=False silently dropped — reasoning field missing from OpenRouter request body guidance source-backed?

The "Pydantic AI thinking=False silently dropped for OpenRouter and other reasoning models" page is labeled source-backed. It has 1 public source URL from github.com, so use that evidence status when deciding how much additional verification you need.

When should I avoid the quick fix for model_settings thinking=False silently dropped — reasoning field missing from OpenRouter request body?

For "Pydantic AI thinking=False silently dropped for OpenRouter and other reasoning models", avoid applying "Compare the failing environment with a known working setup, then change one configuration value at a time." when the error text differs, the affected version or provider is different, or the change would touch credentials, billing, DNS, production deploy settings, or irreversible data.

What should I collect before debugging model_settings thinking=False silently dropped — reasoning field missing from OpenRouter request body?

For "Pydantic AI thinking=False silently dropped for OpenRouter and other reasoning models", collect the failing OpenRouter command or request, non-secret configuration, versions, timestamps, request IDs when available, and the smallest reproduction that still triggers the signature.