AI agents increasingly operate over extended time horizons, yet their ability to retain, organize, and recall multimodal experiences remains a critical bottleneck. Building effective lifelong memory requires navigating a vast design space spanning architecture, retrieval strategies, prompt engineering, and data pipelines; this space is too large and interconnected for manual exploration or traditional AutoML to explore effectively. We deploy an autonomous research pipeline to discover Omni-SimpleMem, a unified multimodal memory framework for lifelong AI agents. Starting from a naïve baseline (F1=0.117 on LoCoMo), the pipeline autonomously executes ∼50 experiments across two benchmarks, diagnosing failure modes, proposing architectural modifications, and repairing data pipeline bugs, all without human intervention in the inner loop. The resulting system achieves state-of-the-art on both benchmarks, improving F1 by +411% on LoCoMo (0.117→0.598) and +214% on Mem-Gallery (0.254→0.797) relative to the initial configurations. Critically, the most impactful discoveries are not hyperparameter adjustments: bug fixes (+175%), architectural changes (+44%), and prompt engineering (+188% on specific categories) each individually exceed the cumulative contribution of all hyperparameter tuning, demonstrating capabilities fundamentally beyond the reach of traditional AutoML. We provide a taxonomy of six discovery types and identify four properties that make multimodal memory particularly suited for autoresearch, offering guidance for applying autonomous research pipelines to other AI system domains. Code is available at this https://github.com/aiming-lab/SimpleMem.
Figures & tables
Figure 1: Overview of the Discovery Process of Omni-SimpleMem . (a) Discovered architecture: multimodal inputs are filtered for novelty, compressed into MAUs, and retrieved via hybrid dense-sparse-graph search with pyramid expansion. (b) Autonomous optimization trajectory on Mem-Gallery: 39 experiments improve F1 from 0.254 to 0.793 (+214%).
Figure 2: Omni-SimpleMem architecture overview. Left: Selective ingestion filters multimodal inputs (text, image, audio, video) via modality-specific novelty detectors and creates MAUs with LLM-generated summaries and embeddings. Center: MAUs are stored in hot storage (summaries, embeddings, metadata) and cold storage (raw content), with entity extraction building a knowledge graph with typed entities and relations. Right: Retrieval combines dense (FAISS), sparse (BM25), and graph ( h -hop) search via set-union merging, then progressively expands results through a pyramid mechanism (summaries → full text → raw content) under a token budget B .
Figure 3: Optimization trajectories on LoCoMo (top, 9 iterations) and Mem-Gallery (bottom, 39 experiments across 7 phases). Solid lines denote accepted iterations; failed/reverted experiments are marked with × . The dashed red line indicates the previous SOTA. Key discoveries at each stage are annotated.
LoCoMo
Mem-Gallery
Backbone
Method
MH
SH
Tmp
Open
Adv
All
F1
EM
B
B-1
B-2
GPT-4o
MemVerse
0.260
0.157
0.196
0.192
0.944
0.365
0.505
0.330
0.270
0.440
0.355
Mem0
0.309
0.156
0.217
0.295
0.857
0.397
0.298
0.192
0.182
0.268
0.224
Claude-Mem
0.294
0.153
0.167
0.243
0.915
0.383
0.210
0.148
0.148
0.194
0.170
A-MEM
0.295
0.174
0.200
0.266
0.898
0.394
0.370
0.252
0.240
0.332
0.285
MemGPT
0.305
0.188
0.246
0.305
0.843
0.404
0.435
0.298
0.275
0.390
0.335
Table 1: Comparison across five LLM backbones on LoCoMo (left) and Mem-Gallery (right). LoCoMo columns: MH = multi-hop, SH = single-hop, Tmp = temporal, Open = open-domain, Adv = adversarial, All = overall F1. Mem-Gallery columns: F1, EM = exact match, B/B-1/B-2 = BLEU/BLEU-1/BLEU-2. Best baseline (excl. Omni-SimpleMem ) is underlined ; best overall is bold .
Component Removed
Δ F1
Rel.
w/o Pyramid Expansion
− 10.2
− 17%
w/o BM25 Hybrid
− 8.5
− 14%
w/o LLM Summarization
− 7.3
− 12%
Reduced top- k (5 vs 20)
− 4.2
− 7%
w/o Metadata Context
− 1.4
− 2%
Table 2: Component ablation on LoCoMo (mean Δ F1 × 100 across 4 backbones).
Figure 4: Throughput vs. F1. Omni-SimpleMem with 8 workers achieves 3.5 × higher throughput.
Method
q/s
Ret.
Gen.
SimpleMem
1.68
45
550
MemVerse
1.48
70
596
Mem0
1.46
18
665
Omni-SimpleMem (w=1)
1.05
118
846
Omni-SimpleMem (w=8)
5.81
461
821
Ret./Gen. in milliseconds.
Table 3: Latency breakdown.
Appendix figures & tables5 assets
Supplementary material from the paper’s appendix.
Appendix
Component
Parameter
Value
Visual Ingestion
CLIP threshold τhigh
0.9
CLIP threshold τlow
0.7
Frame buffer size
3
Audio Ingestion
VAD threshold
0.5
Text Ingestion
Jaccard threshold τdup
0.8
Entity Resolution
Merge threshold τres
0.85
Appendix
Table 4: Hyperparameter specification of Omni-SimpleMem .
Parameter
LoCoMo
Mem-Gallery
Embedding
text-emb-3-large
MiniLM-L6-v2
Embedding dim
3072
384
top- k
20–30
20–40 †
Token budget
6,000
2K–8K †
Per-doc memory
No
Yes
System prompt
Yes
Yes
Appendix
Table 5: Per-benchmark configurations discovered by the autonomous pipeline ( † varies per question category).
Iter
Key Discovery
F1
Δ
Type
0
Naïve baseline
0.117
—
—
1
JSON response_format missing
0.322
+175%
Bug fix
2
BM25 hybrid
0.464
+44%
Architecture
3
Anti-hallucination prompting
0.516
+11%
Prompt
4b
Evaluation format alignment
0.543
+5%
Format
5
MAU timestamp correction
0.580
+7%
Data repair
Appendix
Table 6: Optimization trajectory on LoCoMo. The pipeline autonomously discovers 7 successive improvements and correctly reverts 2 failed experiments.
Phase
Focus
F1 Range
Δ
Key Discovery
1
Environment setup
0.254 → 0.353
+39%
LLM upgrade + local embedding
2
Architecture
0.353 → 0.690
+96%
Full-text retrieval + image BM25
3
Fine-tuning
0.690 → 0.717
+4%
Constraint position sensitivity
4
Scale validation
0.717 → 0.726
+1%
Data completeness > algorithms
5
Exact citation
0.726 → 0.771
+6%
BM25 tokenization fix (+0.018)
6
Visual reasoning
0.771 → 0.789
+2%
Image catalog + context
Appendix
Table 7: Optimization trajectory on Mem-Gallery (39 experiments, 7 phases). Each phase represents a qualitative shift in the pipeline’s optimization strategy.
Iter
Cat1 (MH)
Cat2 (T)
Cat3 (O)
Cat4 (SH)
Cat5 (A)
Baseline
0.093
0.047
0.116
0.219
0.000
Iter 1
0.206
0.117
0.229
0.381
0.447
Iter 2
0.292
0.117
0.282
0.418
1.000
Iter 3
0.351
0.335
0.346
0.444
1.000
Iter 4b
0.389
0.309
0.382
0.466
1.000
Iter 5
0.398
0.487
0.388
0.445
1.000
Appendix
Table 8: LoCoMo per-category F1 across iterations (conv-26, 199 QA pairs).