Mode.BEDROCK_TOOLS missing from from_response parsing

[aum-wmcginnis]

https://github.com/567-labs/instructor/blob/main/instructor/function_calls.py#L190

When using Mode.BEDROCK_TOOLS I get an exception here that object dict doesn't have attribute choices. It looks like it's missing from the if else ladder so is not parsed at all, Mode.BEDROCK_JSON seems to work.

[jxnl]

@claude please fix and make a PR

[claude[bot]]

Claude finished @jxnl's task —— View job

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Analysis and Fix for Mode.BEDROCK_TOOLS Parsing Issue

Todo List:

• [x] Read repository guidelines (CLAUDE.md)
• [x] Investigate function_calls.py parsing logic around line 190
• [x] Identify how BEDROCK_JSON and other modes are handled
• [x] Implement fix for Mode.BEDROCK_TOOLS
• [ ] Run linting and type checking (requires Bash tool permission)
• [ ] Commit changes and create PR (requires Bash tool permission)

Issue Analysis:

Found that Mode.BEDROCK_TOOLS was missing from the if-else ladder in function_calls.py around line 190. The mode exists in mode.py and is supported by the bedrock client, but the response parsing was not implemented.

Solution Implemented:

• Added Mode Handler: Added Mode.BEDROCK_TOOLS case to the from_response method at lines 220-221
• Implemented Parser Method: Created parse_bedrock_tools method to handle Bedrock's tool response format
• Error Handling: Includes proper handling for incomplete outputs and malformed responses
• AWS Bedrock Compliance: Works with the AWS Bedrock Converse API response structure

Implementation Details:

The parse_bedrock_tools method:

1. Checks for incomplete output by comparing outputTokens with maxTokens
2. Extracts content from Bedrock's nested response format (output.message.content)
3. Filters for tool_use type content items
4. Extracts the input field containing function arguments
5. Validates exactly one tool call and returns validated Pydantic model

Files Modified:

• instructor/function_calls.py: Added missing Mode.BEDROCK_TOOLS handler and parse_bedrock_tools method

Status:

✅ Implementation Complete - The core fix has been implemented and follows existing patterns in the codebase.

⚠️ Pending Tasks - Need Bash tool permission to complete:

• Linting: uv run ruff check instructor examples tests
• Type checking: uv run pyright
• Git operations: git add, git commit, git push

The implementation should resolve the issue where Mode.BEDROCK_TOOLS caused "object dict doesn't have attribute choices" errors, allowing proper structured output parsing for AWS Bedrock when using tool calling.

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