File size: 11,905 Bytes
3d9f5ca
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
---
language:
- en
license: apache-2.0
tags:
- distillation
- knowledge-distillation
- json-extraction
- structured-output
- information-extraction
- gemma-4
- minicpm5
- edge-ai
- schemaforge
pipeline_tag: text-generation
base_model: openbmb/MiniCPM5-1B
library_name: transformers
metrics:
- accuracy
- f1
- throughput
---

# SchemaForge-1B β€” JSON Extractor

**A 1.08B-parameter edge SLM distilled from Gemma-4 for zero-shot enterprise JSON extraction.**

SchemaForge-1B converts unstructured business documents β€” invoices, bills of lading, requisitions, receipts β€” into strongly-typed, schema-conformant JSON. It was distilled from **`google/gemma-4-31B`** and **`google/gemma-4-E4B-it`** into **`openbmb/MiniCPM5-1B`** using a multi-task objective combining hard cross-entropy with temperature-scaled, log-space soft-logit KL divergence ($\alpha = 0.5$, $\tau = 2.0$), trained on an NVIDIA RTX PRO 6000 Blackwell Edition (96 GB).

| | 31B Teacher | **SchemaForge-1B** |
|---|---|---|
| In-domain JSON syntax error rate *(n = 5 docs)* | 0.0 % | **0.0 %** |
| In-domain extraction F1 *(n = 5 docs)* | 1.000 | **1.000** |
| Zero-shot validity (`suneeldk/text-json`) | β€” | **70.0 %** |
| Throughput | 12.40 tok/s | **61.91 – 76.27 tok/s** |
| Peak VRAM | β‰ˆ38.5 GB | **β‰ˆ2.4 GB** |
| Workers per 96 GB GPU | 2 | **36** |

**16.0Γ— smaller Β· 5.0Γ— faster Β· ~110Γ— aggregate system throughput**

---

## ⚠️ Read This First: The Prompt Template Is Not Optional

This model was distilled on **one exact prompt template**. Because it is a 1.08B student trained on a narrow task, it binds its behavior to the **literal surface form** of that prefix. In our experiments, changing only the instruction header dropped zero-shot validity from **70.0 % to 0.0 %** β€” worse than the *untrained* base model.

Use this string, byte for byte:

```python
TEMPLATE = "Extract structured JSON from the text:\n{doc}\nJSON Output:"
```

Do not wrap it in chat tokens. Do not prepend a system persona. Do not add a trailing newline. Treat it as a versioned API contract.

---

## πŸ“Š Benchmark Evidence

### 1. Throughput and VRAM

![Figure 1: Inference throughput vs VRAM footprint](https://huggingface.co/arrochi112/SchemaForge-1B-JSON-Extractor/resolve/main/graphs/throughput_vs_vram.png)

*Figure 1: **5.0Γ— throughput speedup** (61.91 vs. 12.40 tok/s, matched harness) and **16.0Γ— VRAM reduction** (β‰ˆ2.4 GB vs. β‰ˆ38.5 GB), measured on identical hardware.*

### 2. Zero-shot accuracy across distillation iterations

![Figure 2: Zero-shot JSON accuracy across iterations](https://huggingface.co/arrochi112/SchemaForge-1B-JSON-Extractor/resolve/main/graphs/accuracy_across_iterations.png)

*Figure 2: Validity on `suneeldk/text-json`. Iterations 1 and 3 differ from the winning Iteration 2 **only in prompt header** β€” and both collapse to 0.0 %.*

### 3. Training convergence

![Figure 3: Training loss convergence](https://huggingface.co/arrochi112/SchemaForge-1B-JSON-Extractor/resolve/main/graphs/loss_convergence.png)

*Figure 3: Loss over 3 epochs, Gemma-4-31B teacher. Iteration 2 (released): 9,132.9 β†’ 6,962.3 β†’ 6,612.7 (βˆ’27.6 %). Summed losses β€” comparable within a run, not across runs.*

---

## Quickstart

```python
import torch
from transformers import AutoTokenizer, AutoModelForCausalLM

model_id = "arrochi112/SchemaForge-1B-JSON-Extractor"

tokenizer = AutoTokenizer.from_pretrained(model_id)
model = AutoModelForCausalLM.from_pretrained(
    model_id,
    dtype=torch.bfloat16 if torch.cuda.is_available() else torch.float32,
).to("cuda" if torch.cuda.is_available() else "cpu")
# No trust_remote_code needed β€” MiniCPM5-1B is a stock LlamaForCausalLM.

# CANONICAL TEMPLATE β€” do not modify
prompt = (
    "Extract structured JSON from the text:\n"
    "INVOICE #INV-1001. Vendor: Acme Supply Co. Date: 2026-04-10. "
    "Subtotal: $480.00. Tax (8%): $38.40. Total: $518.40.\n"
    "JSON Output:"
)

inputs = tokenizer(prompt, return_tensors="pt").to(model.device)
with torch.no_grad():
    outputs = model.generate(**inputs, max_new_tokens=128, do_sample=False)

print(tokenizer.decode(outputs[0][inputs["input_ids"].size(1):],
                       skip_special_tokens=True))
```

Expected:

```json
{
  "invoice_number": "INV-1001",
  "vendor_name": "Acme Supply Co",
  "invoice_date": "2026-04-10",
  "subtotal": 480.00,
  "tax": 38.40,
  "grand_total": 518.40
}
```

---

## Production Serving (vLLM)

```python
from vllm import LLM, SamplingParams

llm = LLM(
    model="arrochi112/SchemaForge-1B-JSON-Extractor",
    dtype="bfloat16",
    gpu_memory_utilization=0.90,
    max_model_len=2048,
    max_num_seqs=36,               # 36 workers fit in 96 GB at 2.4 GB each
)

sampling_params = SamplingParams(temperature=0.0, max_tokens=256)

TEMPLATE = "Extract structured JSON from the text:\n{doc}\nJSON Output:"
docs = [
    "Invoice #INV-881, Vendor: Globex Corp, Date: 2026-08-03, Total: $450.00",
    "Invoice #INV-882, Vendor: Initech LLC, Date: 2026-08-04, Total: $1200.00",
]

for out in llm.generate([TEMPLATE.format(doc=d) for d in docs], sampling_params):
    print(out.outputs[0].text)
```

### Recommended: layer schema-constrained decoding

Distillation supplies *semantics*; FSM-guided decoding guarantees *syntax*. Run both.

```python
from pydantic import BaseModel
from vllm.sampling_params import GuidedDecodingParams

class Invoice(BaseModel):
    invoice_number: str
    vendor_name: str
    invoice_date: str
    subtotal: float
    tax: float
    grand_total: float

sampling_params = SamplingParams(
    temperature=0.0,
    max_tokens=256,
    guided_decoding=GuidedDecodingParams(json=Invoice.model_json_schema()),
)
```

---

## Evaluation

### Five-domain enterprise suite (in-domain, n = 5 documents)

| Domain | Document type | Base MiniCPM5-1B | **SchemaForge-1B** | F1 | Throughput |
|---|---|---|---|---|---|
| BMK-01 Finance | Tax invoices | 65.8 % | **100.0 %** | 1.000 | 61.91 tok/s |
| BMK-02 Supply chain | Bills of lading | 67.1 % | **100.0 %** | 1.000 | 62.40 tok/s |
| BMK-03 IT hardware | Procurement bills | 64.2 % | **100.0 %** | 1.000 | 61.80 tok/s |
| BMK-04 Biomedical | Lab requisitions | 66.5 % | **100.0 %** | 1.000 | 62.15 tok/s |
| BMK-05 Cloud ops | Billing records | 65.4 % | **100.0 %** | 1.000 | 62.05 tok/s |

### Model comparison

| Variant | Teacher | JSON error rate | F1 | Throughput | VRAM |
|---|---|---|---|---|---|
| Base MiniCPM5-1B | none | 34.2 % | 0.612 | 62.00 tok/s | β‰ˆ2.4 GB |
| **SchemaForge-1B** | `gemma-4-E4B-it` | **0.0 %** | **1.000** | **61.91 tok/s** | **β‰ˆ2.4 GB** |
| **SchemaForge-1B** | `gemma-4-31B` | **0.0 %** | **1.000** | 56.12 tok/s | **β‰ˆ2.4 GB** |
| Gemma-4-31B | reference | 0.0 % | 1.000 | 12.40 tok/s | β‰ˆ38.5 GB |

Teacher scale conferred **no measurable quality advantage** on this task β€” the 4B teacher is the cost-effective choice.

### Out-of-domain (`suneeldk/text-json`)

| Iteration | Prompt template | Validity | Throughput |
|---|---|---|---|
| iter1 | chat tokens (`<start_of_turn>`) | 0.0 % | 76.94 tok/s |
| **iter2 (this model)** | **canonical** | **70.0 %** | **76.27 tok/s** |
| iter3 | system persona header | 0.0 % | 74.12 tok/s |
| base | canonical | 34.2 % | 62.00 tok/s |

---

## Training Details

| | |
|---|---|
| Architecture | `LlamaForCausalLM` β€” 24 layers, hidden 1536, GQA 16/2 heads, vocab 130,560 |
| Parameters | 1,080,632,832 total (679,552,512 non-embedding) |
| Objective | $\mathcal{L}_{KD} = \alpha\mathcal{L}_{CE} + (1-\alpha)\tau^2\mathcal{L}_{KL}$ |
| $\alpha$ / $\tau$ | 0.5 / 2.0 |
| Vocabulary projection | 256,000 β†’ 130,560 (shared-subspace truncation) |
| Optimizer | AdamW, lr 2e-5, cosine, warmup 0.05 |
| Epochs | 3 (early-stopped on val loss) |
| Runtime | bfloat16, single-GPU PyTorch, eager attention (no ZeRO-3 / FlashAttention-2) |
| Max sequence length | 2,048 |
| Hardware | 1 Γ— NVIDIA RTX PRO 6000 Blackwell Edition (96 GB), Nebius AI Cloud |
| Software | Python 3.12 Β· PyTorch 2.5 Β· transformers 5.x |

Full methodology, mathematics, compatibility patches, and ablations: **[`SCHEMAFORGE_WHITEPAPER.md`](./SCHEMAFORGE_WHITEPAPER.md)**.

---

## Limitations

Please read these before deploying.

- **Evaluation scale is small.** The in-domain suite is **n = 5 documents** (one per domain). The 100 % validity / 1.000 F1 figures are exact-match results on a small curated set, not population estimates β€” the Wilson 95 % CI on 5/5 is **[56.6 %, 100.0 %]**.
- **Training scale is small.** This checkpoint was distilled on **n = 5 samples**. An SFT control ($\alpha = 1.0$, no teacher logits) was **not run**, so we cannot presently separate the contribution of knowledge distillation from that of prompt-format conditioning.
- **Single seed.** No variance estimates or error bars. Sub-2B models vary substantially run-to-run on small datasets.
- **Prompt-template brittleness.** The headline failure mode. Deviating from the canonical template drops accuracy to ~0, not to a degraded-but-usable level.
- **Out-of-domain ceiling β‰ˆ 70 %.** Roughly 30 % of unseen real-world documents produce unparseable output. Use constrained decoding in production.
- **Synthetic in-domain documents.** Clean ASCII, consistent labeling, no OCR noise, English-only. Real scanned documents will be harder.
- **Teacher outputs as targets.** Where the teacher was wrong, the student learned the error. No human-annotated gold standard exists for this checkpoint.
- **Not evaluated against alternatives.** No comparison to Qwen2.5-1.5B, Phi-3-mini, rule-based extractors, or commercial document-AI APIs.

**Intended use:** structured extraction from short English business documents, behind a schema-validation layer.
**Out of scope:** open-domain chat, reasoning, code, multilingual input, medical/legal decision-making, or any use where an unvalidated extraction reaches a system of record.

### Planned v2 run

This is a **v1 release**, and the accuracy numbers above should be read as provisional. A second training and evaluation campaign is planned to address the limitations listed here directly:

- **Real-world evaluation corpus** replacing the synthetic 5-document suite β€” $n \geq 500$ held-out documents per domain, including OCR-noisy scans, multi-column layouts, and non-English fields, with a **human-annotated gold subset** so accuracy is no longer measured against teacher output.
- **The SFT control** ($\alpha = 1.0$, no teacher logits) to determine whether the distillation objective contributes anything beyond prompt-format conditioning.
- **Competitive baselines** β€” Qwen2.5-1.5B, Phi-3-mini, prompt-engineered base MiniCPM5-1B with constrained decoding, and a rule-based extractor β€” under one unified harness.
- **Multi-seed runs** (β‰₯3) with reported variance and confidence intervals on every metric.
- **Expanded metrics** beyond validity/F1/throughput/VRAM: per-field accuracy, schema-conformance rate, hallucinated-key rate, time-to-first-token, p50/p95 latency under concurrency, and cost per thousand documents.

Results will be published as a v2 card revision with the v1 numbers retained for comparison rather than quietly replaced.

---

## Citation

```bibtex
@techreport{ty2026schemaforge,
  title  = {SchemaForge: Distilling Ultra-Large Foundation Models into Edge SLMs
            for Real-Time Enterprise JSON Extraction --
            A Comparative Study of Gemma-4 Teachers and MiniCPM5-1B},
  author = {Ty, Arjhine A.},
  year   = {2026},
  note   = {Model: SchemaForge-1B (schemaforge-1b-iter2)},
  url    = {https://huggingface.co/arrochi112/SchemaForge-1B-JSON-Extractor}
}
```

## Acknowledgements

Teachers: `google/gemma-4-31B`, `google/gemma-4-E4B-it`. Student architecture: `openbmb/MiniCPM5-1B`. Compute: Nebius AI Cloud. Serving: vLLM. Constrained decoding: Outlines.

**License:** Apache 2.0 β€” subject to the upstream licenses of the base and teacher models.