SKILL-DISCO: Distilling and Compiling Agent Traces into Reusable Procedural Skills
Pith reviewed 2026-06-26 05:01 UTC · model grok-4.3
The pith
SkillDisCo distills reusable parameterized control-flow subgraphs from successful agent traces and compiles them into callable procedural skills.
A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.
Core claim
In FSM-defined scenarios, successful traces can be viewed as paths in an unknown transition graph, and procedural skills can be formulated as reusable parameterized control-flow subgraphs. SkillDisCo distills these PFSM subgraphs from traces and compiles them into callable, executable, and verifiable procedural skills, which improves success rates and reduces agent turns on ALFWorld and WebArena across benchmarks and model scales.
What carries the argument
Reusable parameterized control-flow subgraphs (PFSM subgraphs) distilled from traces, which capture shared execution structure and compile into callable procedural skills.
Load-bearing premise
Successful traces can be viewed as paths in an unknown transition graph and procedural skills can be formulated as reusable parameterized control-flow subgraphs in FSM-defined scenarios.
What would settle it
A test in which SkillDisCo is applied to the same traces and models on ALFWorld and WebArena but produces no increase in success rates or decrease in agent turns.
Figures
read the original abstract
Agents often repeatedly solve similar task instances from scratch, leading to unnecessary reasoning cost and long execution traces. Prior work has explored workflow reuse and executable skill induction, but it remains unclear which task scenarios admit procedural skills and how the shared procedural structure should be represented across successful traces. We study this problem in FSM-defined scenarios, where successful traces can be viewed as paths in an unknown transition graph, and formulate procedural skills as reusable parameterized control-flow subgraphs. Based on this view, we introduce SkillDisCo, a distillation-and-compilation framework that distills reusable PFSM subgraphs from successful traces and compiles them into callable, executable, and verifiable procedural skills. Experiments on ALFWorld and WebArena show that SkillDisCo improves success rates and reduces agent turns across benchmarks and model scales, demonstrating the benefits of representing shared experience as reusable execution structures.
Editorial analysis
A structured set of objections, weighed in public.
Referee Report
Summary. The paper claims that in FSM-defined scenarios, successful agent traces can be viewed as paths in an unknown transition graph, and formulates procedural skills as reusable parameterized control-flow subgraphs (PFSM). It introduces SkillDisCo, a distillation-and-compilation framework that extracts such subgraphs from traces and compiles them into callable, executable, and verifiable skills. Experiments on ALFWorld and WebArena report improved success rates and reduced agent turns across benchmarks and model scales.
Significance. If the central modeling assumptions and empirical gains hold, the work offers a structured approach to reusing procedural experience as verifiable execution structures rather than repeated reasoning from scratch. The PFSM representation provides a concrete, potentially falsifiable way to capture shared control-flow across task instances.
major comments (2)
- [§3] §3 (Modeling): The central claim requires that successful traces admit a clean decomposition into reusable parameterized PFSM subgraphs whose parameters transfer across instances. For WebArena, dynamic page states, JavaScript execution, and partial observability make a fixed transition graph difficult to maintain without heavy abstraction; the paper must show that the distillation step reliably recovers such subgraphs rather than relying on environment-specific engineering.
- [§5] §5 (Experiments): The reported gains in success rate and reduced turns are load-bearing for the claim that the PFSM representation is beneficial. The manuscript must include ablations that isolate the contribution of the parameterized subgraph representation versus alternative distillation methods or non-FSM skill induction, along with statistical significance, variance across runs, and controls for trace quality.
minor comments (1)
- [Abstract] Abstract: The phrase 'across benchmarks and model scales' should specify the exact models, number of runs, and precise metrics (e.g., success rate deltas) to allow immediate assessment of the strength of the empirical claim.
Simulated Author's Rebuttal
We thank the referee for the detailed and constructive comments. We address each major point below and indicate the revisions we will make to strengthen the manuscript.
read point-by-point responses
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Referee: [§3] §3 (Modeling): The central claim requires that successful traces admit a clean decomposition into reusable parameterized PFSM subgraphs whose parameters transfer across instances. For WebArena, dynamic page states, JavaScript execution, and partial observability make a fixed transition graph difficult to maintain without heavy abstraction; the paper must show that the distillation step reliably recovers such subgraphs rather than relying on environment-specific engineering.
Authors: The framework is explicitly scoped to FSM-defined scenarios where an underlying transition structure can be abstracted from observations. For WebArena we employ a state abstraction that encodes page elements and action effects while abstracting away transient JavaScript dynamics; the distillation procedure then operates uniformly on the resulting traces. We will revise §3 to explicitly document this abstraction, include examples of recovered parameterized subgraphs that transfer across WebArena task instances, and add a short analysis showing that the extracted subgraphs are not artifacts of bespoke engineering. revision: yes
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Referee: [§5] §5 (Experiments): The reported gains in success rate and reduced turns are load-bearing for the claim that the PFSM representation is beneficial. The manuscript must include ablations that isolate the contribution of the parameterized subgraph representation versus alternative distillation methods or non-FSM skill induction, along with statistical significance, variance across runs, and controls for trace quality.
Authors: We agree that isolating the contribution of the parameterized PFSM representation and providing statistical support are necessary. In the revised §5 we will add (i) an ablation replacing parameterized subgraphs with non-parameterized and non-FSM baselines, (ii) mean and standard deviation of success rate and turn count over five independent runs per setting, (iii) paired t-tests for significance, and (iv) a control experiment that substitutes lower-quality traces. These additions will be reported for both ALFWorld and WebArena. revision: yes
Circularity Check
No circularity: framework formulation with no equations or fitted predictions
full rationale
The paper presents SkillDisCo as a distillation-and-compilation framework based on viewing traces as paths in an FSM transition graph and skills as parameterized PFSM subgraphs. This is introduced as a modeling choice in the abstract and full text, without any equations, derivations, parameter fitting, or predictions that reduce to inputs by construction. No self-citations, ansatzes, or uniqueness theorems are invoked in a load-bearing way. The experimental claims rest on empirical results rather than any self-referential reduction. This is the common case of a self-contained descriptive framework.
Axiom & Free-Parameter Ledger
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