docs(bedrock): document userContext for Knowledge Base search

[mateo-berri]

TLDR

Documents the userContext field for Bedrock Knowledge Base searches, which BerriAI/litellm#41475 forwards on the Retrieve request so stores with document-level ACLs return only what the named user may see

Adds a "Restrict Results to a User" section to the Bedrock Knowledge Bases page covering the LiteLLM SDK, the OpenAI SDK against the proxy, curl against the proxy, and a user_context set on the store in vector_store_registry, with the precedence rule between the two

Pairs with LIT-4415

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Note

Low Risk
Documentation-only change with no runtime or security behavior changes in this diff.

Overview
Adds a Restrict Results to a User section to the Bedrock Knowledge Bases docs, explaining how to pass Bedrock userContext so ACL-enabled Knowledge Bases return only chunks visible to the named user.

The section documents four call paths—LiteLLM SDK vector_stores.search via extra_body, proxy search with the OpenAI SDK and curl, and default identity via user_context in vector_store_registry—and notes that per-request userContext overrides config, that userId must be a string, and that LiteLLM does not bind userId to the proxy API key (trusted callers only).

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Project	Deployment	Actions	Updated
litellm	Ready	Preview	Sep 16, 2026 8:07pm UTC

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