feat(bedrock): pass strict and additionalProperties to Converse API toolSpec

[Ryze0323]

Relevant issues

Closes the gap where Anthropic direct API path already supports strict (PR #16725) but Bedrock Converse path does not.

Related: #10062, #16725, #6136

Summary

Bedrock Converse API supports strict: true in toolSpec since 2026-02-04 (GA) — AWS API Reference: ToolSpecification.

Previously, both strict and additionalProperties were implicitly dropped during OpenAI-to-Bedrock tool conversion because ToolSpecBlock and ToolJsonSchemaBlock only whitelisted a subset of fields (introduced in #10062, which was correct at the time since Bedrock didn't support strict).

Without additionalProperties: false in the schema, Bedrock rejects strict: true requests with:

"For 'object' type, 'additionalProperties' must be explicitly set to false"

This PR:

• Adds strict: Optional[bool] to ToolSpecBlock TypedDict
• Adds additionalProperties: bool to ToolJsonSchemaBlock TypedDict
• Passes through both parameters in _bedrock_tools_pt() when present
• Adds unit test verifying both fields are passed through (and absent when not specified)

Pre-Submission checklist

• I have Added testing in the tests/test_litellm/ directory, Adding at least 1 test is a hard requirement - see details
• My PR passes all unit tests on make test-unit
• My PR's scope is as isolated as possible, it only solves 1 specific problem
• I have requested a Greptile review by commenting @greptileai and received a Confidence Score of at least 4/5 before requesting a maintainer review

Type

🆕 New Feature

Changes

• litellm/types/llms/bedrock.py: Added strict: Optional[bool] to ToolSpecBlock, additionalProperties: bool to ToolJsonSchemaBlock
• litellm/litellm_core_utils/prompt_templates/factory.py: Pass through strict and additionalProperties from OpenAI tool format to Bedrock toolSpec
• tests/llm_translation/test_bedrock_completion.py: Updated test_bedrock_tools_pt_strict_parameter test to cover both fields

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Project	Deployment	Actions	Updated (UTC)
litellm	Ready	Preview, Comment	Apr 8, 2026 3:56am

[Ryze0323]

@greptileai - Updated: applied P2 style feedback (dict-spread instead of post-construction mutation)

[greptile-apps]

Greptile Summary

This PR closes the gap between the Anthropic direct API path (which already supports strict) and the Bedrock Converse path by passing strict and additionalProperties through _bedrock_tools_pt() to the Bedrock toolSpec. The changes are minimal and well-scoped: two TypedDict fields are added, the conversion function is updated with proper None-safe conditional dict-spread, and a focused unit test validates both the pass-through and the absence cases.

Key changes:

• ToolJsonSchemaBlock gains additionalProperties: bool — required by Bedrock when strict: true is requested (Bedrock returns an error without it)
• ToolSpecBlock gains strict: Optional[bool] — minor nit: since the TypedDict is already total=False, plain bool would be cleaner (see inline comment)
• _bedrock_tools_pt() correctly guards both fields with is not None checks, so additionalProperties: False (falsy but valid) is still forwarded
• The test covers the two main branches: both fields present and neither field present

Confidence Score: 5/5

Safe to merge — only one P2 style nit remains; no correctness or reliability issues.

The change is narrow and correct: two optional fields are forwarded through an existing conversion function with proper falsy-safe guards. The test validates both the pass-through and absence paths. The only open finding is a P2 type-annotation nit (Optional[bool] vs bool in a total=False TypedDict) which has no runtime impact.

No files require special attention.

Vulnerabilities

No security concerns identified. The change only passes through user-supplied schema fields (strict, additionalProperties) to the Bedrock Converse API — no auth, credential, or injection surface is touched.

Important Files Changed

Filename	Overview
litellm/types/llms/bedrock.py	Adds additionalProperties: bool to ToolJsonSchemaBlock and strict: Optional[bool] to ToolSpecBlock; minor nit: Optional[bool] in a total=False TypedDict allows None values that the production code deliberately avoids.
litellm/litellm_core_utils/prompt_templates/factory.py	Correctly extracts additionalProperties from parameters and strict from tool["function"], passing each through only when non-None via dict-spread; logic is clean and handles False (falsy) values properly.
tests/llm_translation/test_bedrock_completion.py	New unit test covers both the "with strict + additionalProperties" and "without either field" paths; no network calls; could also test each field independently but the primary scenarios are exercised.

Flowchart

%%{init: {'theme': 'neutral'}}%%
flowchart TD
    A["OpenAI tool format\n{ function: { name, strict, parameters: { ..., additionalProperties } } }"] --> B["_bedrock_tools_pt()"]
    B --> C{additionalProperties\nin parameters?}
    C -- yes --> D["Include additionalProperties\nin BedrockToolJsonSchemaBlock"]
    C -- no --> E["Omit additionalProperties"]
    D --> F["BedrockToolInputSchemaBlock"]
    E --> F
    B --> G{strict in\nfunction?}
    G -- yes --> H["Include strict\nin BedrockToolSpecBlock"]
    G -- no --> I["Omit strict"]
    F --> J["BedrockToolSpecBlock\n{ inputSchema, name, description, [strict] }"]
    H --> J
    I --> J
    J --> K["BedrockToolBlock\n{ toolSpec: ... }"]
    K --> L["Bedrock Converse API"]

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_{Reviews (7): Last reviewed commit: "feat(bedrock): pass strict and additiona..." | Re-trigger Greptile}

[Ryze0323]

@ishaan-jaff @krrishdholakia This PR is ready for review — all CI checks pass and Greptile gave 5/5 confidence. Could you take a look when you get a chance? Thanks!

[Ryze0323]

@greptileai review

[codspeed-hq]

Merging this PR will not alter performance

✅ 16 untouched benchmarks

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_{Comparing Ryze0323:feat/bedrock-strict-tool-support (c51fb46) with main (62757ff)}

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

📢 Thoughts on this report? Let us know!

[Ryze0323]

@yuneng-berri Could you take a look when you get a chance? All CI checks pass and Greptile gave 5/5 confidence. Thanks!

[github-actions]

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