Strands integration ignores RetrievalConfig.relevance_score when injecting AgentCore Memory context

[nakedible]

Summary

In the Strands integration, RetrievalConfig.relevance_score is defined/configurable but appears to be ignored when retrieving and injecting AgentCore Memory results into agent.messages. This leads to low-relevance memories being injected even when a high threshold is configured.

Where

src/bedrock_agentcore/memory/integrations/strands/session_manager.py

• AgentCoreMemorySessionManager.retrieve_customer_context(...) (and its inner retrieval/injection logic)

Expected behavior

If RetrievalConfig.relevance_score is set (e.g. 0.9), only memory records with relevanceScore >= relevance_score should be injected into the <user_context>...</user_context> block, mirroring the behavior in:

• src/bedrock_agentcore/memory/session.py → MemorySessionManager._retrieve_memories_for_llm(...) (client-side filtering by relevanceScore)

Actual behavior

The Strands integration injects whatever the service returns in the top_k results (and concatenates their content.text), without applying the configured minimum relevance threshold.

Why this matters

• Injects irrelevant context → worse model outputs
• Increased context size / token usage
• Confusing UX because the option exists (and has a default) but does not affect behavior

Steps to reproduce

1. Configure Strands with AgentCore Memory session manager and a high threshold:

   RetrievalConfig(top_k=10, relevance_score=0.9, ...)

2. Ensure retrieval returns at least one record with a low relevanceScore (e.g. 0.1–0.3) and at least one with a high score (e.g. 0.9+). (This can be done by mocking memory_client.retrieve_memories(...) in a unit test.)
3. Send a user message that triggers retrieve_customer_context.
4. Observe that the injected <user_context> includes the low-score record(s) despite the threshold.

Suggested fix

Apply the same client-side filtering used by MemorySessionManager._retrieve_memories_for_llm(...) inside the Strands retrieval path before building the injected context:

• If relevance_score is non-zero, filter memory records by record.get("relevanceScore", ...) >= relevance_score.

Environment

• bedrock-agentcore-sdk-python: v1.1.1 (also reproducible on main as of Dec 2025)
• strands-agents: (please fill)
• Python: (please fill)