[FEATURE] Avoid initializing boto client every single time for S3SessionManager and AgentCore memory.

[CrysisDeu]

Problem Statement

This issue also exist with AgentCore memory

There are a couple issues with the S3SessionManager:

• There is no way to pass an S3SessionManager into the class. A new boto3 s3 client is created every single time.
• The sessionManager class is tied to a sessionId upon initialization. There is no way to update it afterwards. It means there is no way to save a singleton class.

These issue results in added latency for every single agent conversation turn and should be considered anti-patterns.

Proposed Solution

• Let client pass in an S3 client, only create a new one if None is passed in
• Allow the S3SessionManager to be used as a singleton and can be invoked/set to different sessionIds

Use Case

Using strands with S3Session manager or AgentCore memory

Alternatives Solutions

No response

Additional Context

No response

[pgrayy]

I agree that we should allow for reuse of the session manager instance so that user do not have to reinitialize the underlying client. Will consult with team on this.

Regarding the second bullet, can you elaborate a bit more on the concern? Session id being tied to the session manager instance is key for identifying the resources to load upon init.

[yaramubarak-artera]

Im running into a similar issue now when wanting to use agentcore with the s3sessionmanager

[MukundaKatta]

Opened #2301 which adds an optional s3_client= kwarg to S3SessionManager.__init__. When provided, the manager reuses the caller's boto3 S3 client directly instead of constructing a new boto3.Session + client per instance.

The PR is backward-compatible (existing path unchanged when s3_client is omitted) and ships with four new moto-backed tests; the full session/S3 suite is 50 passed locally.

It only addresses the S3 half of this issue — the AgentCore memory side would benefit from the same treatment but lives outside this SDK repo as far as I can see. Happy to take a follow-up if there's a target repo for that piece.