Add unsupported claude code beta headers in json

[Sameerlite]

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Type

🆕 New Feature
🐛 Bug Fix
🧹 Refactoring
📖 Documentation
🚄 Infrastructure
✅ Test

Changes

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Project	Deployment	Actions	Updated (UTC)
litellm	Ready	Preview, Comment	Feb 6, 2026 1:06pm

[greptile-apps]

Greptile Overview

Greptile Summary

• Adds a centralized anthropic_beta_headers_manager + JSON config to drop unsupported anthropic-beta values per provider.
• Wires the filter into Anthropic, Azure AI, Vertex AI, Bedrock Invoke, and Bedrock Converse transformation paths.
• Replaces prior provider-specific filtering logic (Bedrock/Vertex) with the centralized config-driven approach.
• Adds unit tests covering basic filtering/support checks and header update behavior.

Confidence Score: 2/5

• This PR should not be merged until the Bedrock runtime regression and Opus 4.6 structured-outputs handling are fixed.
• Centralizing beta header filtering is a reasonable refactor and tests cover the manager basics, but the Bedrock Converse change can raise UnboundLocalError at runtime and the Bedrock Invoke exception for Opus 4.6 structured-outputs is currently ineffective; both directly impact request correctness.
• litellm/llms/bedrock/chat/converse_transformation.py; litellm/llms/bedrock/messages/invoke_transformations/anthropic_claude3_transformation.py; litellm/anthropic_beta_headers_config.json

Important Files Changed

Filename	Overview
litellm/anthropic_beta_headers_config.json	Adds JSON config listing provider-specific unsupported Anthropic beta headers; contains a duplicate entry in the bedrock list.
litellm/anthropic_beta_headers_manager.py	Introduces a centralized loader/filter to drop unsupported values from the anthropic-beta header based on a JSON config; uses module-level caching.
litellm/llms/anthropic/experimental_pass_through/messages/transformation.py	Calls centralized header filter in Anthropic messages environment validation.
litellm/llms/azure_ai/anthropic/transformation.py	Filters anthropic-beta header for Azure AI requests via centralized manager.
litellm/llms/bedrock/chat/converse_transformation.py	Replaces inline bedrock converse beta filtering with centralized filter and adds model-based computer-use header; introduces UnboundLocalError risk around computer_use_tools usage.
litellm/llms/bedrock/messages/invoke_transformations/anthropic_claude3_transformation.py	Switches bedrock invoke beta filtering to centralized config and adds structured-outputs exception; current re-add logic is ineffective so Opus 4.6 won’t restore structured-outputs.
litellm/llms/vertex_ai/vertex_ai_partner_models/anthropic/experimental_pass_through/transformation.py	Removes bespoke Vertex unsupported-beta removal and uses centralized filter; behavior depends on JSON config.
tests/test_litellm/test_anthropic_beta_headers_manager.py	Adds unit tests for new header manager; tests don’t cover bedrock structured-outputs Opus 4.6 exception or converse computer_use_tools regression.

Sequence Diagram

sequenceDiagram
    participant Caller as LiteLLM caller
    participant ProviderCfg as Provider transform
    participant BetaMgr as anthropic_beta_headers_manager
    participant JSON as anthropic_beta_headers_config.json
    participant Upstream as Provider API

    Caller->>ProviderCfg: create request (headers/optional_params)

    alt Anthropic / Azure AI / Vertex AI
        ProviderCfg->>BetaMgr: update_headers_with_filtered_beta(headers, provider)
        BetaMgr->>BetaMgr: parse 'anthropic-beta' header (comma split)
        BetaMgr->>JSON: load unsupported list (cached)
        BetaMgr-->>ProviderCfg: headers updated (drop unsupported / delete if empty)
        ProviderCfg->>Upstream: send request
    else Bedrock Converse
        ProviderCfg->>BetaMgr: filter_and_transform_beta_headers(beta_headers, bedrock_converse)
        BetaMgr->>JSON: load unsupported list (cached)
        BetaMgr-->>ProviderCfg: filtered list
        ProviderCfg->>Upstream: send request with additional_request_params.anthropic_beta
    else Bedrock Invoke
        ProviderCfg->>ProviderCfg: map advanced-tool-use -> tool-search-tool (+tool-examples)
        ProviderCfg->>BetaMgr: filter_and_transform_beta_headers(beta_headers, bedrock)
        BetaMgr->>JSON: load unsupported list (cached)
        BetaMgr-->>ProviderCfg: filtered list
        ProviderCfg->>Upstream: send request
    end

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[greptile-apps]

_{8 files reviewed, 3 comments}

_{Edit Code Review Agent Settings | Greptile}

[greptile-apps]

Incorrect tool-use gating

anthropic_beta_list.append(computer_use_header) is inside if computer_use_tools:, but computer_use_tools is only defined in the if filtered_tools and self.is_computer_use_tool_used(...) branch. In the else-branch (no computer use tools), computer_use_tools is undefined, which can raise UnboundLocalError at runtime depending on control flow. Consider checking if filtered_tools and self.is_computer_use_tool_used(...): (or guarding with a local computer_use_tools = [] default) before referencing it.

[greptile-apps]

Additional Comments (2)

litellm/anthropic_beta_headers_config.json
Duplicate unsupported header

"code-execution-2025-08-25" appears twice in the bedrock unsupported list. This will cause inconsistent expectations (e.g., in tests that compare lengths) and makes the config harder to reason about. Please remove the duplicate entry so the JSON remains a clean source of truth.

---

litellm/llms/bedrock/messages/invoke_transformations/anthropic_claude3_transformation.py
Structured-outputs never re-added

In _filter_unsupported_beta_headers_for_bedrock, the re-add logic checks if is_opus_4_6 and "structured-outputs-2025-11-13" in beta_list:, but beta_list is built after filtering has already removed structured-outputs (since it’s in the provider unsupported list). This condition will therefore always be false, so Opus 4.6 will never get structured-outputs-2025-11-13 even if the user requested it. Preserve the pre-filter set/list (or check the original beta_set before filtering) for the re-add decision.