Adapting language models to new domains via continual pre-training raises a basic evaluation problem: if the training corpus overlaps with what the model already knows, performance gains cannot be cleanly attributed to new learning rather than pre-existing knowledge. This matters most for knowledge-intensive, task-light (KHTL) robot deployments - pharmaceutical dispensing, hazardous-material handling, facility-specific protocols, where the physical task is simple but the governing rules are proprietary and safety-critical, and where extensive live testing is costly or unsafe. We introduce ORDER (Ontology-driven Decision-making for Embodied Reasoning), a benchmark built on a fictitious world: a 342,069-token synthetic corpus defining a self-consistent physics that cannot appear in any model's pre-training data. ORDER pairs a 500-question knowledge test (ORDER-BENCH) with a harder compositional task, ORDER-SPATIAL: ordering objects for safe manipulation across both familiar and entirely novel scenes. GPT-4.1 without adaptation scores below chance on ORDER-SPATIAL (Kendall's tau = 0.441), showing its priors actively conflict with the invented physics. After continual pre-training, small models improve substantially on both familiar and novel scenes alike evidence of genuine world-model induction rather than memorization. We then carry this through to a robot pipeline: models that answer the knowledge test well often cannot produce valid, executable plans without a further skill-adaptation stage, after which small, fully offline models outperform GPT-4.1 even when GPT-4.1 is given retrieval access to the same rules (Kendall's tau = 0.848 vs. 0.606), on a full perception-to-execution loop demonstrated on a simulated iiwa7 arm with human-in-the-loop correction. Throughout, ORDER-SPATIAL performance, not knowledge-test accuracy is what predicts real plan quality.
Figures & tables
Fig. 2 : The Order framework. Left: the Order-World knowledge pyramid; all upstream context is injected into downstream generation calls. Centre: the two-stage adaptation pipeline, instantiated across seven K-LoRA variants for three SLM families and then extended with S-LoRA skill fine-tuning to produce Domain-BT-LMs (Sections VII – VIII ). Right: Order-Bench , comprising the MCQ component and the Order-Spatial seen/unseen ordering task, with the metric suite of Section IV-C .
Section
Tokens
Role
Master Ontology (0)
67,389
Physics foundation
Axioms (1)
11,886
Global constraints
Counterfactuals (2)
16,336
Constraint stress-tests
QnA (3)
47,836
Format diversification
Spatial Configs (4)
100,214
Scenes & priority orders
Paraphrases (5)
98,408
Format diversification
TABLE I : Order-World token distribution ( D=342,069 tokens).
Category
N
wc
wcN
Intrinsic Semantics
10
1.0
10.0
QnA
30
1.0
30.0
Axioms
60
1.5
90.0
Spatial (MCQ)
72
2.0
144.0
Pairwise
150
2.5
375.0
Counterfactuals
111
2.5
277.5
TABLE II : Order-Bench MCQ composition and Bloom weights. Total weight mass: 1127.5; random baseline: 25%.
Variant
Description
Normal
Packed causal LM over all D sections; all-token CLM loss.
Overfit
Normal extended to near-zero training loss ( L≈0 ).
DKL *
Base ← instruct embedding replacement before CPT [ 43 ] .
RAFT
Retrieval-augmented fine-tuning with hard-negative distractors [ 44 ] .
SSR-CLM
Packed CLM on non-spatial entries; loss-masked SSR (Structured Scene Reasoning) on spatial entries (loss on assistant tokens only, preventing format overfitting).
Unified
SSR-CLM + RAFT + DPO pairs (chosen = oracle-faithful, rejected = parametric-bias) in one training script.
TABLE III : K-LoRA knowledge-ingestion variants.
Model
PPL ↓
Sagg
Sp.MCQ
GPT-4.1
NA
70.4
70.8
M-7B
13.72
48.9
65.3
L-8B
21.79
34.7
44.4
Q-4B
24.22
57.0
69.4
TABLE IV : Closed-book zero-shot performance (PPL on a held-out split of D ). Sp.MCQ ≫Sagg for all SLMs reflects common-sense ordering priors, not domain knowledge; the gap closes only after CPT (Appendix G ).
Category
GPT-4.1
M-7B
L-8B
Q-4B
Axioms
100.0
96.67
98.33
98.33
Intrinsic
100.0
100.0
100.0
100.0
Pairwise
100.0
98.67
96.67
98.67
Higher-Order
100.0
100.0
97.01
100.0
Counterfact.
98.2
93.69
90.09
96.4
QnA
100.0
100.0
100.0
100.0
TABLE V : Order-Bench MCQ with retrieval (global hybrid BM25 + dense pipeline, Appendix A-A ). Non-spatial categories saturate ( ≥90% ), validating corpus coherence. Spatial remains harder for smaller models.
TABLE VI : Order-Spatial : τorder and par for all K-LoRA variants across the three SLM families, on the 70 seen and 183 unseen scenes. Best per family in bold . The random baseline is τorder=0.500 on both splits (Appendix I ); par floors are 0.333 seen and 0.309 unseen. Off-the-shelf Qwen3 already exceeds GPT-4.1; Mistral-RAFT and LLaMA-Unified show inverted seen/unseen gaps.
Fam.
KI
Instruct
Post-KI
Gain
τorders
τorderu
τorders
τorderu
Δs
Δu
M-7B
RAFT
0.528
0.509
0.71
0.73
+ 0.18
+ 0.21
L-8B
Unified
0.513
0.554
0.77
0.81
+ 0.26
+ 0.26
Q-4B
Combined
0.582
0.597
0.79
0.74
+ 0.21
+ 0.14
TABLE VII : Absolute τorder improvement to the best K-LoRA variant per family. Both seen and unseen improve substantially, providing evidence against memorisation ( HA ).
Family
Variant
svr
τorder
sdhr
L-8B
Instruct
12.2
0.057
53.4
Normal
70.7
0.524
72.4
RAFT
31.7
0.216
87.9
Unified
4.9
0.037
53.4
M-7B
Instruct
2.4
0.019
25.9
Normal
4.9
0.035
44.8
TABLE VIII : Zero-shot BT generation of KI-models (82 novel samples, no fine-tuning). Near-zero svr for Mistral and LLaMA variants confirms that domain knowledge and BT-generation skill are separable capabilities. GPT-4.1 vanilla is included as a frontier reference.
Fam.
KI Var.
svr
τorder
par
P-PAR
sdhr
L-8B
Inst. + S-LoRA
100.0
0.830
0.629
36
100.0
Normal
100.0
0.799
0.675
43
100.0
Overfit
100.0
0.813
0.702
46
100.0
DKL
100.0
0.815
0.718
46
100.0
RAFT
100.0
0.833
0.743
50
100.0
Unified
98.8
0.848
0.724
49
98.3
TABLE IX : S-LoRA results - Instruct mounting (82 novel samples). Best per family in bold . P-PAR: n /82 exactly correct sequences.
Fam.
KI Var.
svr
τorder
par
P-PAR
sdhr
L-8B
Normal
100.0
0.781
0.649
40
100.0
Overfit
100.0
0.848
0.736
46
100.0
DKL
100.0
0.831
0.697
44
96.6
RAFT
100.0
0.767
0.574
32
98.3
SSR-CLM
97.6
0.844
0.705
45
91.4
Unified
75.6
0.601
0.497
31
74.1
TABLE X : S-LoRA results - Matched mounting (82 novel samples). Matching the S-LoRA initialisation to the KI-variant benefits LLaMA (Overfit/SSR-CLM) and uniformly stabilises Qwen; most Mistral KI-variants collapse.
Setup
svr
τorder
Closed-book best (RAFT, Instruct)
100.0%
0.833
SLM + full assembled context (unadapted)
0.0%
0.000
SLM + two-stage-cs (adapted)
100.0%
0.798
TABLE XI : Context-hijacking failure and recovery (LLaMA-3.1-8B). Injecting the full assembled ontology context directly into the BT-generation call collapses svr from 100% to 0% in the fine-tuned SLM; the two-stage pipeline with a condensed ( ≤ 800-token) priority-reasoning call restores functional output, though still below the closed-book peak.
Fig. 3 : The two structured retrieval pipelines. Both delegate Stage 1 priority reasoning to a condensed SLM call ( ≤ 800 tokens) rather than injecting the full assembled context into the generation call; the CS variant additionally forces an XML prefix to prevent prose-opening failures. Both share the same weighted retrieval index and no-spatial few-shot conditioning.
Variant / Mount
Pipeline
svr
τorder
par
CB- τorder
LLaMA-3.1-8B
Base-Inst / Inst.
two-stage
100%
0.819
0.686
0.830
Base-Inst / Inst.
two-stage-cs
100%
0.798
0.663
0.830
Overfit / Match.
two-stage
100%
0.811
0.713
0.848
Overfit / Match.
two-stage-cs
99%
0.801
0.714
0.848
12-Comb. / Match.
two-stage
100%
0.824
0.719
0.806
TABLE XII : Structured retrieval results (82 novel samples). CB- τorder is the closed-book reference for the same (variant, mounting) pair. Retrieval revives variants that collapsed closed-book, but does not reach the closed-book peak of 0.848 .
Fig. 4 : End-to-end pipeline snapshots on the iiwa7 in Gazebo. Left: the direct LLM-generated BT XML and execution summary for Configuration #88, given the VLM {O,C,P,R} JSON and the NL user input; the tree commits two errors, placing the grey cylinder at priority 1 (correct: priority 3) and emitting the blue disc as a standalone top-level sequence instead of inside the required Fallback accessibility guard. Centre: the corrected BT XML after a single HITL operator re-prompt, in which EnsureAccessible_brown_cube becomes the first child of MainTask and the blue disc appears only as the conditional blocker-removal step inside it. Top right: the initial Gazebo scene for Configuration #88. Bottom right: the iiwa7 arm grasping the first-priority object (the blue disc, the stacking blocker) and placing it in the blue colour bin.
Fig. 5 : Worked HITL correction example (Configuration #88). Top: the scene, with the blue disc stacked on the brown cube (blocking access), and the Order priority order. Left: the LLM-generated tree commits two errors: (i) the grey cylinder is placed at P1 instead of P3, and (ii) the blue disc appears as a standalone top-level Sequence rather than inside the required Fallback guard, missing the CheckStackSafety structure entirely. Right: the gold tree places EnsureAccessible_brown_cube as the first Fallback child of MainTask ; the blue disc appears only inside it as the conditional blocker-removal step, and the remaining three children follow the correct Order -derived priority order. Bottom: the single operator correction prompt that drives the Domain-BT-LM to regenerate the gold tree in one pass. The operator either approves the BT with ‘y’ or starts with ‘n’ followed by the correction prompt.
Fam.
KI / S-LoRA
τorderu
svr
sdhr
τorder
par
P-PAR
GPT-4.1 Vanilla
0.44
96.3
100
0.480
0.420
22
GPT-4.1 + two-stage-cs
-
-
-
0.606
-
10
LLaMA-3.1-8B - Instruct S-LoRA (closed-book)
L-8B
Unified / Inst.
0.81
98.8
98.3
0.848
0.724
49
L-8B
RAFT / Inst.
0.60
100
100
0.833
0.743
50
L-8B
DKL / Inst.
0.58
100
96.6
0.815
0.718
46
TABLE XIII : Domain-BT-LMs vs. GPT-4.1 (82 novel samples). All Domain-BT-LM results are closed-book (no retrieval at inference); the GPT-4.1 reference uses its best structured pipeline (two-stage-cs). τorderu is the Order-Spatial unseen concordance from Section VI-E (random baseline =0.500 ), included to trace the knowledge-to-action chain. † SSR-CLM collapses under Instruct mounting ( \textscsvr=0 ); the Matched result is shown. ‡ Mistral-RAFT/Inst. is the best Mistral result overall.
Appendix figures & tables12 assets
Supplementary material from the paper’s appendix.
Appendix
Knowledge Type
Weight
Order
Counterfactual constraints
1.00
1st
Pairwise inter-object (contact)
0.90
2nd
Dominance axioms
0.85
3rd
Higher-order emergent regimes
0.80
4th
Pairwise intra-object
0.70
5th
Intrinsic primitive semantics
0.55
6th
Appendix
TABLE XIV : Knowledge-type weighting used for context assembly.
M-7B
L-8B
Q-4B
Variant
PPL
Loss
PPL
Loss
PPL
Loss
Normal
3.82
0.230
7.22
0.820
8.89
1.110
Overfit
3.10
0.021
6.04
0.016
6.79
0.059
DKL
2.07
0.027
4.72
0.015
6.06
0.085
RAFT
3.44
0.823
5.27
1.660
6.53
2.650
SSR-CLM
1.52
0.003
2.52
0.002
4.62
0.001
Appendix
TABLE XV : PPL and training loss for all K-LoRA variants. SSR-CLM achieves the lowest PPL but dissociates from spatial performance. Mistral-Unified collapses silently.
Seen ( n=70 )
Unseen ( n=183 )
Metric
Mean
Std
Mean
Std
t
Structural
Num. objects
3.29
0.97
3.53
0.97
−1.76
Unique primitives
9.53
2.06
9.63
2.47
−0.34
Spatial relations
2.29
0.97
2.45
0.98
−1.19
Physics (activation counts)
Appendix
TABLE XVI : Complexity distribution across Order-Spatial splits. Seen and unseen are statistically comparable across all axes (Welch t -tests: all ∣t∣<2 , p>0.05 ). The mild four-object skew in unseen ( 30.6% vs. 18.6% ) slightly disfavours unseen performance.
Family
Variant
τ^s
zs
τ^u
zu
M-7B
RAFT
0.710
+3.51∗∗∗
0.730
+6.20∗∗∗
L-8B
Unified
0.770
+4.52∗∗∗
0.810
+8.39∗∗∗
Q-4B
Combined
0.790
+4.85∗∗∗
0.740
+6.49∗∗∗
GPT-4.1
Vanilla
0.441
−0.99
0.415
−2.30∗
Appendix
TABLE XVII : One-sided z -test results. ∗p<0.05 , ∗∗p<0.01 , ∗∗∗p<0.001 .
Variant
Intr.
QnA
Axioms
Pair
CFact
HO
Spat.
Sagg
Normal
80.0
60.0
58.3
62.0
64.0
53.7
69.4
61.8
Overfit
70.0
70.0
45.0
68.0
64.9
50.8
63.9
61.9
DKL
80.0
66.7
58.3
70.0
65.8
56.7
52.8
63.5
RAFT
70.0
36.7
25.0
54.0
36.9
41.8
44.4
43.8
SSR-CLM
66.7
61.7
69.3
72.1
77.6
43.1
67.7
Unified
10.0
0.0
1.7
3.3
1.8
0.0
0.0
1.8
Appendix
TABLE XVIII : Mistral-7B-Instruct-v0.3 - section-wise MCQ (%).
Variant
Intr.
QnA
Axioms
Pair
CFact
HO
Spat.
Sagg
Normal
60.0
30.0
48.3
43.3
48.7
49.3
36.1
45.0
Overfit
80.0
66.7
63.3
59.3
61.3
52.2
45.8
57.5
DKL
90.0
83.3
58.3
78.0
58.6
59.7
61.1
66.5
RAFT
80.0
33.3
40.0
42.7
52.3
46.3
55.6
47.2
SSR-CLM
90.0
88.3
84.0
79.3
70.1
65.3
78.6
Unified
70.0
83.3
60.0
79.3
70.3
71.6
68.1
72.8
Appendix
TABLE XIX : LLaMA-3.1-8B-Instruct - section-wise MCQ (%).
Variant
Intr.
QnA
Axioms
Pair
CFact
HO
Spat.
Sagg
Normal
80.0
73.3
83.3
74.0
52.3
55.2
73.6
66.0
Overfit
90.0
83.3
86.7
81.3
56.8
73.1
69.4
72.9
DKL
90.0
83.3
98.3
94.0
75.7
98.5
62.5
86.3
RAFT
90.0
63.3
71.7
63.3
47.7
56.7
59.7
58.8
SSR-CLM
83.3
94.0
78.4
95.5
70.8
87.5
Unified
93.3
90.0
89.3
70.3
91.0
80.6
84.1
Appendix
TABLE XX : Qwen3-4B-Instruct-2507 (thinking mode) - section-wise MCQ (%).
Variant
MMLU-Pro
GSM8K
BBH
IFEval
Instruct
37.5
84.4
51.0
75.0
Normal
33.8
74.5
50.6
56.8
Overfit
34.3
76.3
50.7
57.9
DKL
36.6
82.6
50.4
73.2
RAFT
36.2
83.4
50.3
74.5
SSR-CLM
33.1
76.2
50.6
62.3
Appendix
TABLE XXI : General benchmark retention: LLaMA-3.1-8B-Instruct.
Variant
MMLU-Pro
GSM8K
BBH
IFEval
Instruct
30.6
51.9
44.9
47.9
Normal
26.9
52.5
43.4
44.9
Overfit
27.2
48.9
42.6
46.8
DKL
27.6
48.3
43.1
43.8
RAFT
28.3
50.7
44.9
47.1
SSR-CLM
25.7
33.0
41.2
38.3
Appendix
TABLE XXII : General benchmark retention: Mistral-7B-Instruct-v0.3.
Variant
MMLU-Pro
GSM8K
BBH
IFEval
Instruct
43.9
77.6
54.6
82.4
Normal
43.4
86.4
55.9
81.3
Overfit
43.8
82.4
54.9
79.3
DKL
38.9
74.0
50.8
79.8
RAFT
38.6
73.6
51.4
77.2
SSR-CLM
39.2
76.5
50.8
79.6
Appendix
TABLE XXIII : General benchmark retention: Qwen3-4B-Instruct-2507.
Family
Variant
ΔSagg
Δτorderu
ΔGen↓
Profile
L-8B
Unified ⋆
+38.1
+0.26
2.2
best spatial
L-8B
SSR-CLM
+43.9
+0.19
6.4
best MCQ
L-8B
Combined
+43.4
+0.15
8.4
high risk
M-7B
RAFT ⋆
−5.1
+0.21
1.1
spatial + min. forg.
M-7B
DKL ⋆
+14.6
+0.18
4.1
factual + spatial
M-7B
SSR-CLM
+18.8
+0.00
9.3
MCQ only
Appendix
TABLE XXIV : Retention–domain trade-off summary per family. ΔSagg and Δτorderu are improvements over the instruct baseline; ΔGen is the mean absolute drop across the four general benchmarks (0 if improved; lower is better). ⋆ Pareto-recommended: strong domain gains with low forgetting cost.
Fig. 6 : The perception layer is a fixed, domain-agnostic prompt over the visual grammar of Eq. 1 . All interaction semantics live in Order-World , not in the VLM, which is why the same perception module serves any KHTL domain expressed over these primitives.