Organizations: Institute of Software Chinese Academy of Sciences, Beijing, China · Science & Technology on Integrated Information System Laboratory, Beijing, China · State Key Laboratory of Complex System Modeling and Simulation Technology, Beijing, China · University of Chinese Academy of Sciences, Beijing, China · Beijing University of Post and Telecommunications, Beijing, China
Agents increasingly rely on reusable skills to encode task knowledge, tool-use procedures, and validation rules. Existing skill self-evolution methods primarily revise skills using execution trajectories collected from current tasks, leaving the evolution knowledge accumulated in public skill version histories largely untapped. Our pilot study reveals a clear complementarity between the two sources: public skill changes provide reusable evolution priors, whereas trajectories provide evidence grounded in the current task. Motivated by this, we propose VCE-Skill, which distills noisy and implementation-specific public skill changes into reusable, structured version-change experience and adaptively fuses it with trajectory-derived proposals from the base evolver, thereby exploiting external experience while retaining task-specific evidence. Extensive experiments demonstrate that VCE-Skill improves skill self-evolution, increasing mean scores by 3.20--4.98 points; transfer experiments further show that the resulting skills achieve stronger cross-model transfer performance. Our work highlights public skill version changes as a previously underexplored yet effective source of prior knowledge and advances trajectory-driven skill self-evolution.
Figures & tables
Figure 1: Public and trajectory-derived skill changes.
Figure 2: Overview of VCE-Skill. The left stage distills the version-change experience from public skill versions. The right stage enhances the skill self-evolution by allocating adaptive attention between external experience and trajectory-derived proposals.
Figure 3: Illustration of experience distillation.
Model
Skill
SearchQA
OfficeQA
ALFWorld
Spreadsheet
BFCL-v4
Avg.
No Skill
68.42
33.79
52.87
26.93
54.75
47.35
LLM Skill
67.29
33.41
54.74
29.48
55.12
48.01
EvoSkill
67.08
34.13
57.46
39.45
58.45
51.31
EvoSkill+VCE
70.46 (+3.38)
41.79 (+7.66)
59.13 (+1.67)
45.13 (+5.68)
60.71 (+2.26)
55.44 (+4.13)
SkillClaw
69.41
36.12
59.01
42.46
61.23
53.65
SkillClaw+VCE
72.48 (+3.07)
41.48 (+5.36)
62.48 (+3.47)
46.73 (+4.27)
63.77 (+2.54)
57.39 (+3.74)
Table 1: Performance comparison on different models and benchmarks. For VCE-enhanced variants, red (green) parenthesized values indicate improvements (declines) over their corresponding baseline. Bold indicates the best result.
Figure 4: The performance of different variants of VCE-Skill.
Target Model
Source Skill
SearchQA
OfficeQA
ALFWorld
Spreadsheet
BFCL-v4
Avg.
SkillOpt
78.01
47.47
79.16
52.11
64.10
64.17
GPT-5.2
SkillOpt+VCE
83.24
55.34
86.05
57.89
68.54
70.21 (+6.04)
SkillOpt
71.16
44.94
69.60
38.16
62.10
57.19
DeepSeek-v3.2
SkillOpt+VCE
78.12
49.53
75.11
43.94
65.48
62.44 (+5.25)
SkillOpt
81.10
53.03
83.69
56.01
66.42
68.05
Claude Sonnet 5
SkillOpt+VCE
87.37
58.14
86.80
61.73
71.97
73.20 (+5.15)
Table 2: Cross-model transfer performance of skills.
Appendix figures & tables15 assets
Supplementary material from the paper’s appendix.
Appendix
Dimension
Annotation target
Decision rule
Component
Affected skill artifacts
Assign all affected artifact types, including instructions, scripts, references, configurations, and templates.
Intent
Objective of the update
Assign the primary outcome pursued by the change.
Pattern
Modification strategy
Abstract the operational mechanism into a repository-independent family.
Appendix
Table 1: Annotation dimensions and selected taxonomy labels used in the representative skill-change units.
Component
Instruction + Script
Operation
Modify + Modify
Intent
INTENT_10 : Compatibility and interoperability
Pattern Family
FAMILY_08 : Executable workflow automation
Appendix
Figure 1: Representative skill-change units from public version histories and trajectory-driven evolution. The public update coordinates instruction and executable-code changes to preserve compatibility with an external service. The trajectory-derived update adds a local extraction rule in response to an observed SearchQA failure.
Figure 2: Skill counts, substantive version updates, and affected-component shares across 12 task domains in the broader public-history survey. Component shares are non-exclusive because one update may affect several artifacts.
Figure 3: Trajectory utility and validation-score change across skill-evolution iterations.
Failure-mode coverage
Δ Train ↑
Δ Test ↑
Gap ↓
P2F ↓
Low (1–3 modes)
4.82
2.54
2.28
12.7
Medium (4–8 modes)
4.17
2.81
1.36
9.7
High (9–10 modes)
4.23
3.19
1.04
5.9
Appendix
Table 2: Training-test gaps and pass-to-fail regressions under different failure-mode coverage.
Symbol
Meaning
uj
update event ⟨dj,{cj},oj,ij⟩ containing a raw diff segment, affected components, semantic operation, and intent
B
version-change experience bank containing update patterns, evolution insights, and domain insights
St
target skill retained by the base evolver after online iteration t
τt
task-execution trajectory produced with St
zt
selection context containing target task, current skill, and available prior feedback
Xt
at most five experience entries selected from B
Appendix
Table 3: Core notation used in the implementation.
Figure 13Figure 14Figure 15Figure 16Figure 17
Figure 13: Ablation results averaged over all five benchmarks. Each panel uses EvoSkill, SkillClaw, or SkillOpt as the base self-evolver. w/o Dist replaces distilled experience with raw version changes, and w/o Atte assigns equal weights to external experience and self-generated proposals. Higher is better.
Source Model
Target Model
Source Skill
SearchQA
OfficeQA
ALFWorld
Spreadsheet
BFCL-v4
Avg.
Avg. Gain
Qwen3.5-27B
GPT-5.2
SkillOpt
78.01
47.47
79.16
52.11
64.10
64.17
–
SkillOpt+VCE-Skill
83.24
55.34
86.05
57.89
68.54
70.21
6.04
DeepSeek-v3.2
SkillOpt
71.16
44.94
69.60
38.16
62.10
57.19
–
SkillOpt+VCE-Skill
78.12
49.53
75.11
43.94
65.48
62.44
5.25
Claude Sonnet 5
SkillOpt
81.10
53.03
83.69
56.01
66.42
68.05
–
SkillOpt+VCE-Skill
87.37
58.14
86.80
61.73
71.97
73.20
5.15
Appendix
Table 4: Complete cross-model transfer results over all 12 directed source–target model pairs. Each source-trained skill is directly applied to the target model without further evolution. Avg. reports the mean performance across the five benchmarks, and Avg. Gain reports the mean improvement of SkillOpt+VCE-Skill over SkillOpt computed from the unrounded results. Bold indicates the higher result within each source–target pair.
Parameter
Value
SearchQA
OfficeQA
ALFWorld
Spreadsheet
BFCL-v4
K
3
76.24
47.54
61.30
51.39
55.98
4
78.75
49.34
63.38
52.12
57.42
5
78.86
49.42
63.43
52.14
57.52
6
78.03
48.82
62.76
51.59
57.03
7
76.98
48.07
61.90
50.89
56.41
η
0.01
75.16
46.96
61.42
50.67
56.34
Appendix
Table 5: Hyperparameter sensitivity of SkillOpt+VCE-Skill with Qwen3.5-27B. Each row reports mean performance on five benchmarks while varying one hyperparameter and fixing the remaining settings to their defaults. Bold indicates the best score within each hyperparameter group.
Decision Type
Samples
HAR (%) ↑
κ↑
Motivation study
Motivation-study Taxonomy
200
94.0
0.84
Skill-Change Coding
200
100.0
0.84
VCE-Skill method
Change Abstraction
200
92.5
0.82
Experience Generation
200
90.5
0.78
Appendix
Table 6: Human audit results for the LLM-based semantic decisions. HAR is computed from the final adjudicated labels, whereas κ measures agreement between the two initial annotators before adjudication.