fix(bedrock): read reasoningText on non-streaming Converse responses

[Jiaaqiliu]

What does this PR do?

AWS Converse has two different shapes for reasoning content:

• non-streaming ReasoningContentBlock — a union whose text member is {"reasoningText": {"text", "signature"}}
• streaming ReasoningContentBlockDelta — puts "text" at the top level

normalize_converse_response used the streaming shape on the non-streaming response:

elif "reasoningContent" in block:
    reasoning = block["reasoningContent"]
    if isinstance(reasoning, dict):
        thinking_text = reasoning.get("text", "")     # always "" here
        if thinking_text:
            reasoning_parts.append(str(thinking_text))

So reasoning.get("text") was always empty and reasoning_content always None on non-streaming calls. The reasoning box never rendered, reasoning-token accounting saw nothing, and nothing was stored for replay. reasoningText appears nowhere in the tree (grep -rn reasoningText → 0 hits before this PR).

The streaming handler in stream_converse_response is correct for its shape, so this is a mismatch between the two functions rather than a systematic omission.

Reproduction

from agent.bedrock_adapter import normalize_converse_response

resp = normalize_converse_response({
    "output": {"message": {"role": "assistant", "content": [
        {"reasoningContent": {"reasoningText": {"text": "MY REASONING", "signature": "sig"}}},
        {"text": "done"},
    ]}},
    "stopReason": "end_turn",
    "usage": {"inputTokens": 10, "outputTokens": 5},
})

resp.choices[0].message.reasoning_content
# before: None
# after:  'MY REASONING'

Hit by any model that emits reasoningContent on a non-streaming converse() call — us.deepseek.r1-v1:0 emits it unconditionally, and Claude models do with extended thinking enabled via additionalModelRequestFields.

Related Issue

No open issue found. #21202 (merged) added reasoningContent handling to normalized responses but used the delta shape; #36261 is about preserving the reasoning signature on interleaved-thinking replay, which is a separate concern and unaffected by this change.

Fixes #

Type of Change

• 🐛 Bug fix (non-breaking change that fixes an issue)

Changes Made

• agent/bedrock_adapter.py — normalize_converse_response reads the reasoningText.text union member, falling back to the flat text form so a caller passing an already-flattened block keeps working. A block carrying only redactedContent correctly yields no text.
• tests/agent/test_bedrock_adapter.py — new TestNonStreamingReasoningContent: union member preserved, flat form still accepted, redacted-only yields None, absent reasoning yields None.

How to Test

pytest tests/agent/test_bedrock_adapter.py -q

70 passed (66 existing + 4 new). Reverting only the source change makes test_reasoning_text_union_member_is_preserved fail with None != 'The user wants the file. I should call read_file.'.

Checklist

Code

• I've read the Contributing Guide
• My commit messages follow Conventional Commits
• I searched for existing PRs to make sure this isn't a duplicate
• My PR contains only changes related to this fix
• I've run pytest tests/agent/test_bedrock_adapter.py -q and all tests pass
• I've added tests for my changes

[Enough1122]

AI code review — automated review for reference; please use your judgment.

Correct shape fix with the AWS union documented inline where future readers need it: non-streaming ReasoningContentBlock nests text under reasoningText, and the tolerant fallback keeps already-flattened delta blocks working. Tests cover the union member, the flat legacy shape, redacted-only blocks (no phantom text), and full absence — all four outcomes that matter.

— reviewer-b (automated review)

No blocking issues found.