[guojunyuan2004]

Team

旅游凑一队

Summary

Implement PowerMemMiddleware for the VLDB 2026 summer school Task 1: integrate PowerMem as long-term memory for LangChain v1 agents via the middleware API.

Solution Description

Wire PowerMem into LangChain v1 agents via three middleware hooks: before_agent retrieves memories for the latest user message, wrap_model_call injects them into the system prompt, and after_agent writes the exchange back when save_interactions=True. Both sync and async paths are supported; retrieval and write-back are fail-open.

Design notes worth keeping for future readers:

• powermem_context is overwritten on every run (including None) so a checkpointer cannot leak a previous run's memory into the next.
• An AsyncMemory in the sync hooks raises TypeError rather than silently doing nothing.
• user_id comes only from the constructor; no global or implicit identity.

Tests: 20 functions; the six names required by the scoring contract are present verbatim. See packages/powermem-langchain/ for details.

[LINxiansheng]

LangChain Contract Score

LangChain Contract Score
========================
score: 100.00 / 100
suites: 2
rule: A weighted capability receives credit only when it passes on every configured Python suite and all declared prerequisite capabilities also receive credit. Gate tests are reported but do not add points.

Public import contract: PASS (gate)
  py311: passed
  py312: passed
Retrieve memory before model call: PASS (35/35)
  py311: passed
  py312: passed
Persist interaction after agent run: PASS (25/25)
  py311: passed
  py312: passed
Disable interaction persistence: PASS (10/10)
  py311: passed
  py312: passed
Fail-open on search error: PASS (15/15)
  py311: passed
  py312: passed
Async memory injection: PASS (15/15)
  py311: passed
  py312: passed

LangChain Contract Report

LangChain Contract Report
=========================
score: 100.00 / 100
rule: A weighted capability receives credit only when it passes on every configured Python suite and all declared prerequisite capabilities also receive credit. Gate tests are reported but do not add points.

Suite Summary
-------------
py311: passed=25/25, failures=0, errors=0, skipped=0
py312: passed=25/25, failures=0, errors=0, skipped=0

Gate Checks
-----------
Public import contract [gate] PASS
  - py311: passed
  - py312: passed

Weighted Breakdown
------------------
Retrieve memory before model call [35/35] PASS
  - py311: passed
  - py312: passed
Persist interaction after agent run [25/25] PASS
  - py311: passed
  - py312: passed
Disable interaction persistence [10/10] PASS
  - py311: passed
  - py312: passed
Fail-open on search error [15/15] PASS
  - py311: passed
  - py312: passed
Async memory injection [15/15] PASS
  - py311: passed
  - py312: passed

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