[v6.0] fix(amazon-bedrock): support reasoningContent.redactedContent from the Converse API - #19139

Background

redactedContent is the second member of the documented ReasoningContentBlock union (reasoningText | redactedContent) and a member of ReasoningContentBlockDelta, but neither the response schema nor the stream schema accepts it. Models that emit it — e.g. OpenAI models on Converse such as us.openai.gpt-5.6-luna, which return their encrypted reasoning in this shape alongside tool calls — currently fail validation:

• generateText / generateObject with tools throw AI_APICallError: Invalid JSON response on an HTTP 200 response, making tool calling unusable
• streamText with tools emits a spurious AI_TypeValidationError error part on every request and loses the reasoning block

Summary

• Both Zod schemas accept redactedContent (response ReasoningContentBlock and stream contentBlockDelta.delta).
• The payload is surfaced as a reasoning part carrying providerMetadata.{amazonBedrock,bedrock}.redactedContent, mirroring how redactedReasoning is surfaced today.
• convert-to-amazon-bedrock-chat-messages replays it as reasoningContent: { redactedContent } on subsequent turns.
• Streaming deltas are accumulated in the content-block state and attached once via reasoning-end: a reasoning part's merged provider metadata is last-write-wins, so per-delta metadata would drop earlier chunks if the payload ever arrives split.
• Existing redactedReasoning / data handling is left untouched.

Surfacing + replay (rather than accept-and-drop) matters because the encrypted payload restores the model's reasoning state across tool-use turns. Verified against the raw Converse API with a two-turn tool conversation: replaying the block verbatim yields a correct answer from restored state (22 output tokens); stripping it forces the model to re-reason from scratch (509 output tokens) and it loses its earlier conclusion. Replaying via the legacy redactedReasoning: { data } shape is silently ignored by the current API, so a dedicated replay path for the documented shape is required.

Verification

• pnpm test in packages/amazon-bedrock: 465 tests pass. The new tests (response mapping, stream accumulation across split deltas, multi-block separation, replay conversion) fail without the fix.
• End-to-end against real Bedrock (us-east-1, us.openai.gpt-5.6-luna), both doGenerate and doStream: turn 1 surfaces the reasoning part with redactedContent metadata, the turn-2 request contains the replayed reasoningContent.redactedContent block on the wire, no error parts, and the model answers from its restored reasoning state.

Tasks

• Tests have been added / updated (for bug fixes / features)
• Documentation has been added / updated (for bug fixes / features) — provider docs describe reasoning provider metadata generically; no doc change needed
• A patch changeset for relevant packages has been added (for bug fixes / features - run pnpm changeset in the project root)
• Formatting issues have been fixed (run pnpm prettier-fix in the project root)

Future Work

Anthropic models' redacted reasoning on the current Converse API is also documented as redactedContent; this change covers them as well, while keeping the legacy redactedReasoning / data paths for compatibility.

Related Issues

Closes #19062 (full reproduction and multi-turn replay measurements). Related: #19024 (closed; streaming variant of this validation error), #14720 (precedent for OpenAI-on-Converse reasoning handling).

Closes #19115

Backport of #19058