Selective Knowledge Control for Continual GUI Agent Learning over Application Streams
Authors: Zirui Shang, Xin Shu, Yang Liu, Zhi Gao, Xinxiao Wu, Lifeng Fan
Organizations: Beijing Key Laboratory of Intelligent Information Technology, School of Computer Science & Technology, Beijing Institute of Technology · State Key Laboratory of General Artificial Intelligence, BIGAI · Wuhan University · Guangdong Laboratory of Machine Perception and Intelligent Computing, Shenzhen MSU-BIT University
Continual learning is a crucial capability for Graphical User Interface (GUI) agents to adapt to evolving applications while retaining knowledge acquired from previous applications. Such application streams pose a challenging knowledge modeling problem: new applications often share underlying knowledge with past ones, yet also introduce specific knowledge that must not interfere with historical knowledge. In this paper, we propose activation-conditioned selective knowledge control, a lightweight method that achieves selective knowledge retention via neuron-level gradient manipulation. Our method maintains a compact historical knowledge state to protect highly activated MLP neurons that preserve previous knowledge. When a new application arrives, it performs real-time gradient surgery conditioned on forward activation. Concretely, the protected neurons are categorized into two types: unactivated neurons holding specific knowledge, whose gradients are truncated to prevent interference; and activated neurons holding shared knowledge, whose gradients are orthogonally projected to preserve stability while enabling adaptation. After each application stage, newly identified critical neurons are merged into the historical state for future learning. Empirical evaluations on multi-app sequential benchmark demonstrate that our method effectively mitigates catastrophic forgetting on prior applications while sustaining robust adaptation to new ones.
Figures & tables
Figure 1: Example of shared and application-specific knowledge across GUI tasks. Exporting a spreadsheet in LibreOffice Calc and an image in GIMP shares the procedure of opening the File menu, selecting Export , and interacting with an export dialog, while the subsequent steps are application-specific.
Figure 2: Overview of the proposed activation-conditioned selective knowledge control framework. Within each training stage, forward activations partition protected historical neurons into shared and application-specific subsets, and backward gradient surgery applies different update rules to these subsets. After the stage ends, the historical knowledge state is updated with newly identified important neurons and their historical direction subspaces.
Method
Stage
VLC
Thunderbird
Writer
Impress
Calc
GIMP
VS Code
Chrome
Overall
Baseline
Stage 1
37.3
–
–
–
–
–
–
–
37.3
Stage 2
33.3
42.2
–
–
–
–
–
–
37.5
Stage 3
29.4
33.3
47.6
–
–
–
–
–
37.7
Stage 4
33.3
42.2
46.0
37.9
–
–
–
–
39.5
Stage 5
25.5
48.9
39.7
42.4
15.1
–
–
–
31.9
Stage 6
23.5
53.3
33.3
45.5
13.5
57.7
–
–
35.5
Table 1: Average success rates (%) over three runs on all seen applications after each training stage. Parentheses show signed percentage-point differences between ours and the baseline. Column-best results are bolded, and “–” denotes unavailable results.
Stage
Method
RP (%)
CP (%)
RAH (%)
Stage 2
Baseline
89.3
42.2
57.3
Ours
100.0 (+10.7)
51.1 (+8.9)
67.6 (+10.3)
Stage 3
Baseline
78.9
47.6
59.4
Ours
97.7 (+18.9)
57.1 (+9.5)
72.1 (+12.7)
Stage 4
Baseline
95.6
37.9
54.3
Ours
96.5 (+0.9)
47.3 (+9.4)
63.5 (+9.2)
Table 2: Retained performance (RP), current-application performance (CP), and retention–adaptation harmonic score (RAH) during Stages 2–8. Parentheses report the signed percentage-point difference (Ours − Baseline).
Method
Stage
VLC
Thunderbird
Writer
Overall
Baseline
Stage 1
37.3
–
–
37.3
Stage 2
33.3
42.2
–
37.5
Stage 3
29.4
33.3
47.6
37.7
Replay
Stage 1
37.3
–
–
37.3
Stage 2
39.5
40.5
–
40.0
Stage 3
35.3
51.1
46.0
44.0
Table 3: Comparison under the same training configuration. The table reports stage-wise success rates and overall performance for the baseline, replay, EWC, LoRA, and the proposed method.
Setting
Stage 2 (%)
Stage 3 (%)
Mean (%)
Baseline
37.5
37.7
37.6
Static Projection
42.7
40.3
41.5
Static Freezing
41.7
38.4
40.1
Ours
43.8
50.3
47.1
Table 4: Ablation studies on selective control with four update-control settings.
Selection Ratio
VLC
Thunderbird
Writer
Overall
ρ=1%
27.5
51.1
44.4
40.9
ρ=3%
33.3
48.9
48.3
44.2
Ours ( ρ=2% )
35.3
57.8
57.1
50.3
Table 5: Hyperparameter analysis of the selection ratio ρ .
Figure 3: Shared procedural knowledge reuse on a Chrome task.
SVD Rank
rsvd=2
rsvd=4
rsvd=8
Overall Success Rate (%)
38.5
42.7
38.7
Table 6: Hyperparameter analysis of the truncated SVD rank rsvd , reporting the overall success rate (%) at Stage 8 under different numbers of retained historical update directions.
Method
Time (s/step)
Tokens/s
TFLOPs
Baseline
4279.23
400.07
289.79
Ours
4324.00
386.73
284.30
Table 7: Training overhead evaluation. We report per-step training time, token throughput (Tokens/s), and compute throughput (TFLOPs) under the same training configuration.
Method
Stage
VLC
VS Code
GIMP
Overall
Baseline
Stage 1
37.3
–
–
37.3
Stage 2
39.2
65.2
–
54.2
Stage 3
41.2
59.4
66.2
57.4
Ours
Stage 1
37.3
–
–
37.3
Stage 2
39.2
69.6
–
56.7
Stage 3
37.3
63.8
75.6
61.6
Table 8: Application-stream order ablations. The table reports stage-wise success rates and overall performance of the baseline and the proposed method under a shuffled application-stream order.
Figure 4: Shared scope-aware formatting knowledge transferred from Stage 3 Writer to Stage 4 Impress.
Figure 5: Shared destination-aware procedural knowledge transferred from Stage 1 VLC to Stage 8 Chrome.
Figure 6: Layer-wise comparison of stage-wise MLP parameter offsets between ours and the baseline. Rows correspond to the 28 decoder layers, indexed from 0 to 27. (a) Direction similarity Dℓ,t , where zero denotes orthogonal directions. (b) Log displacement ratio log2Rℓ,t , where zero denotes equal update magnitudes. S2–S8 correspond to Thunderbird, Writer, Impress, Calc, GIMP, VS Code, and Chrome, respectively.