LiteLLM / LiteLLM

LiteLLM Structured Output Fails for Anthropic Models on AWS Bedrock

Fix structured output / JSON schema responses failing when using Anthropic models via AWS Bedrock through LiteLLM Includes evidence for LiteLLM troubleshooting demand.

Source-backed Last updated May 13, 2026 1 source Needs local verification

Category: LiteLLM
Error signature: BedrockException - structured output (JSON schema) does not work correctly for Anthropic models on Bedrock/converse
Quick fix: Compare the failing environment with a known working setup, then change one configuration value at a time.
Updated: May 13, 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 LiteLLM, 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

BedrockException - structured output (JSON schema) does not work correctly for Anthropic models on Bedrock/converse is a LiteLLM failure pattern reported for developers trying to fix structured output / json schema responses failing when using anthropic models via aws bedrock through litellm. Based on the imported evidence, treat this as a tool-specific troubleshooting page rather than a generic API error.

Why this happens

LiteLLM issue #27846 reports structured output (JSON schema) failing on Converse API for Anthropic models on Bedrock. Users get BedrockException instead of valid structured responses.

Common causes

Developers using LiteLLM's Responses API with Anthropic Claude models on AWS Bedrock expect structured JSON output but get BedrockException. This breaks production pipelines relying on typed responses.
LiteLLM issue #27846 reports structured output (JSON schema) failing on Converse API for Anthropic models on Bedrock. Users get BedrockException instead of valid structured responses.

Quick fixes

Confirm the exact error signature matches BedrockException - structured output (JSON schema) does not work correctly for Anthropic models on Bedrock/converse.
Check the LiteLLM 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 BedrockException - structured output (JSON schema) does not work correctly for Anthropic models on Bedrock/converse exactly before applying the quick fix.
Compare the failing environment with LiteLLM 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 BedrockException - structured output (JSON schema) does not work correctly for Anthropic models on Bedrock/converse mean in LiteLLM?

BedrockException - structured output (JSON schema) does not work correctly for Anthropic models on Bedrock/converse indicates the workflow described by "LiteLLM Structured Output Fails for Anthropic Models on AWS Bedrock" failed in a LiteLLM context. Start by confirming the exact signature and the component that emitted it.

What should I check first for BedrockException - structured output (JSON schema) does not work correctly for Anthropic models on Bedrock/converse?

Check whether this cause matches your environment: Developers using LiteLLM's Responses API with Anthropic Claude models on AWS Bedrock expect structured JSON output but get BedrockException. This breaks production pipelines relying on typed responses.

Is the BedrockException - structured output (JSON schema) does not work correctly for Anthropic models on Bedrock/converse guidance source-backed?

The "LiteLLM Structured Output Fails for Anthropic Models on AWS Bedrock" 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 BedrockException - structured output (JSON schema) does not work correctly for Anthropic models on Bedrock/converse?

For "LiteLLM Structured Output Fails for Anthropic Models on AWS Bedrock", 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 BedrockException - structured output (JSON schema) does not work correctly for Anthropic models on Bedrock/converse?

For "LiteLLM Structured Output Fails for Anthropic Models on AWS Bedrock", collect the failing LiteLLM command or request, non-secret configuration, versions, timestamps, request IDs when available, and the smallest reproduction that still triggers the signature.