Outcome Instruction tuning completed successfully. The model is demonstrably more instruction-following, but benchmark and qualitative evidence show it remains an experimental small language model—not yet a generally reliable production assistant.

Prepared 21 August 2026

Jhelum Labs / W-1.1 research program

Executive summary

W-1.1 Project Instruct converted the pretrained W-1.1-125M causal language model into an instruction-following checkpoint using 300,000 question–answer and task examples. The run completed on an NVIDIA H100 80GB GPU in approximately 60 minutes and produced a final validation loss of 1.951 (perplexity 7.03).

Indicator

Result

Interpretation

Base model

123,688,704 parameters

GPT-style decoder-only causal LM

Instruction data

300,000 examples

285k train / 7.5k validation / 7.5k test

Training

8,906 optimizer steps, 2 epochs

Completed and checkpointed

Final validation

Loss 1.951; perplexity 7.03

Strong fit to held-out instruction format

Full benchmark mean

41.68% preferred accuracy

Mixed capability; weak reasoning consistency

Deployment status

Research preview

Needs stronger evals, safety, serving, and monitoring

Bottom line The training pipeline worked. The model learned the answer format and improved fluency, but its 125M-parameter capacity and data quality limit factual reliability, multi-step math, and robust reasoning. Use it for controlled demonstrations and research, not high-stakes answers.

Report map

Section

Contents

1

Model and experiment definition

2

Dataset construction and governance

3

Instruction-training configuration

4

Training results and diagnostics

5

Qualitative generation tests

6

Benchmark evaluation

7–8

Risk assessment and recommended next phase

Appendices

Artifacts, full metrics, and conclusion

1. Model and experiment definition

The project starts from W-1.1-125M, a pretrained next-token predictor. Instruction tuning does not replace next-token prediction: it teaches the same objective on structured prompts where the desired continuation is an answer. At inference time, the model still predicts one token at a time, conditioned on the instruction and all previously generated tokens.

Component

Specification

Architecture

Decoder-only Transformer / causal language model

Parameters

123,688,704

Vocabulary

32,000 BPE tokens

Context window

2,048 tokens (instruction sequences prepared at 1,024)

Hidden width

768

Transformer blocks

14

Attention heads

12

Feed-forward width

2,048

Core layers

RMSNorm, RoPE, SwiGLU, tied token embedding / LM head

Pretraining corpus consumed

2,825,248,272 tokens

Base checkpoint

best.safetensors (~471.8 MB shown in Drive)

Experiment objective

The objective was to produce an instruction-following variant capable of answering general questions, science prompts, basic mathematics, coding requests, classification, summarization, and creative tasks while retaining the pretrained language knowledge.

Pipeline

Stage

Action

Primary compute

1

Prepare and split 300k instruction examples

Local CPU

2

Stage dataset and base checkpoint from Google Drive to a persistent Modal Volume

CPU / network

3

Tokenize to fixed 1,024-token input and label binaries

CPU

4

Fine-tune the pretrained model with supervised next-token loss

NVIDIA H100

5

Validate, checkpoint, and sync final outputs to Google Drive

GPU + CPU / network

6

Run qualitative generation and standardized benchmarks

GPU

2. Dataset construction and governance

The final instruction corpus contains 300,000 examples. A deterministic split reserved 285,000 examples for training and 7,500 each for validation and testing. The mixture is dominated by OpenOrca, with targeted additions for general instruction following, code, science, and grade-school mathematics.

Source: dataset statistics.json produced by the W-1.1 instruction-data preparation pipeline.

Source

Examples

Share

OpenOrca

198,081

66.0%

Alpaca Cleaned

50,000

16.7%

Python Instructions

18,000

6.0%

Dolly 15k

14,774

4.9%

SciQ

11,672

3.9%

GSM8K

7,473

2.5%

Category coverage

Category

Examples

Category

Examples

Mixed

198,081

Science

11,672

General

50,000

Math

7,473

Code

18,000

Open QA

3,673

Classification

2,131

General QA

2,090

Brainstorming

1,755

Closed QA

1,753

Information extraction

1,500

Summarization

1,178

Creative writing

694

Data-quality and contamination cautions

  • OpenOrca supplies 66.0% of the corpus, so its style and any duplicated or benchmark-derived content can dominate learned behavior.
  • GSM8K and SciQ were directly included in training; they should not be reported as clean independent benchmarks without a decontaminated holdout.
  • Public instruction datasets vary in factuality, formatting, licensing, safety coverage, and duplication. A production release needs documented filtering and provenance checks.

3. Instruction-training configuration

Hyperparameter

Value

Purpose

Sequence length

1,024

Fixed instruction/response training window

Microbatch

8 sequences

Per-forward-pass batch

Gradient accumulation

8

Effective batch: 64 sequences / up to 65,536 tokens

Epochs

2

Two passes through the 285k-example training split

Peak learning rate

1.0 × 10⁻⁵

Conservative adaptation of pretrained weights

Minimum learning rate

1.0 × 10⁻⁶

Cosine-decay floor

Warmup

3%

Stabilizes early optimization

Weight decay

0.05

Regularization

Gradient clipping

1.0

Limits unstable updates

Validation / save interval

250 steps

Frequent monitoring and resumability

Evaluation batches

50

Held-out estimate per validation event

Seed

42

Reproducibility control

Precision / hardware

CUDA on NVIDIA H100 80GB HBM3

High-throughput fine-tuning

The run targeted 8,908 optimizer steps and completed 8,906. The two-step difference is operationally negligible and is consistent with sequence-count rounding or end-of-epoch batching. Checkpoints were committed throughout the run, enabling recovery.

Compute separation The notebook UI could remain on a small CPU kernel while the detached Modal function trained on H100. The notebook submitted and monitored the remote job; the GPU lived inside the training container.

4. Training results and diagnostics

Source: Pasted instruction-training history and final completion metadata.

Validation loss declined smoothly from approximately 2.38 at step 250 toward 2.00 by step 8,750, followed by a final reported evaluation of 1.951. The overall trend is healthy: the model adapted steadily without a sustained validation reversal. Training loss fluctuated batch-to-batch, as expected for a heterogeneous mixture.

Training outcome

Recorded value

Completed steps

8,906

Elapsed time

~60 minutes

Final validation loss

1.9508458743

Final perplexity

7.0346354822

Best periodic validation metric

2.0000909448 at step 8,750

Final checkpoint

Jhelum Labs 125M-instruct-v1.safetensors

Final checkpoint size

593,068,584 bytes (~565.6 MiB)

Training status

Completed and synchronized to Google Drive

Perplexity interpretation

Perplexity is exp(loss). For the final loss, exp(1.9508459) ≈ 7.03. This means the model’s average uncertainty on the held-out instruction tokens is equivalent to choosing among roughly seven plausible next tokens. It is a useful optimization signal, but it does not directly measure truthfulness, safety, or question-answer accuracy.

Operational incidents resolved

Incident

Cause

Resolution

Google Drive token not found

Lightning path was reused inside Modal

Upload token.json to /root and point the script to that location

Function disk request out of bounds

Modal disk value below current allowed minimum

Increase ephemeral disk request to the platform-supported range

CUDA Graph tensor overwrite

torch.compile CUDA Graph interaction across accumulated steps

Disable CUDA Graphs / use safe compile configuration

torch.compile options conflict

mode and options supplied together

Specify only one configuration path

Checkpoint key mismatch

Instruction model used abbreviated norm names

Restore original attn_norm / ffn_norm module names and tied-head handling

5. Qualitative generation tests

Post-training prompts showed clear paragraph-level fluency and instruction-style formatting. The model generated topical continuations for artificial intelligence, education, and narrative prompts. However, the samples also exposed hallmark small-model weaknesses: unsupported citations, repetition, semantic drift, and unreliable arithmetic.

Test area

Observed behavior

Assessment

General expository text

Maintained topic and article-like structure; invented MIT/Nature-style claims

Fluent, not reliably factual

Education prompt

Produced headings and bullet-like advice; grammar and redundancy remained

Useful formatting, weak editing

Creative continuation

Produced a coherent scientist narrative before drifting into unrelated drug-making language

Local coherence, poor long-range control

Discount arithmetic

Repeated the price, confused percentages, and failed to complete the calculation

Unreliable multi-step reasoning

Instruction format

Generally returned an answer continuation rather than raw web-style prose

Instruction tuning worked

Qualitative verdict W-1.1 can demonstrate an answer-oriented interface, but outputs require external verification. It should not be positioned as “fully accurate” or equivalent to a modern production assistant.

6. Benchmark evaluation

Two evaluation passes were observed. The first used small samples and produced wide uncertainty. The final run evaluated the complete benchmark sets and is the authoritative scorecard. Preferred accuracy uses normalized accuracy where provided, otherwise raw accuracy.

Source: W-1.1 smoke benchmark summary and full lm-evaluation-harness result file.

Source: Full benchmark scores; reference baselines are random choice except BoolQ majority-class baseline (approx. 62.2%).

Benchmark

Raw acc.

Preferred

Std. error

Reading

ARC Easy

44.78%

40.70%

±1.01 pp

Above 25% chance

ARC Challenge

20.22%

24.40%

±1.26 pp

Near 25% chance

HellaSwag

27.45%

28.33%

±0.45 pp

Slightly above 25% chance

PIQA

60.17%

58.98%

±1.15 pp

Above 50% chance

WinoGrande

50.43%

50.43%

±1.41 pp

Near 50% chance

BoolQ

59.30%

59.30%

±0.86 pp

Below ~62.2% majority baseline

OpenBookQA

17.60%

29.60%

±2.04 pp

Above 25% chance

The unweighted mean preferred score is 41.68%. This average is a convenient report-card summary, not an official aggregate benchmark because the tasks have different sizes, baselines, and difficulty.

What the scores say

  • Strongest relative result: PIQA at 58.98%, indicating some practical commonsense discrimination.
  • Moderate result: ARC Easy at 40.70%, showing partial elementary science knowledge.
  • Weakest areas: ARC Challenge, HellaSwag, WinoGrande, and OpenBookQA remain close to simple baselines.
  • BoolQ accuracy is below the dataset’s approximate majority baseline, so the raw percentage should not be interpreted as strong yes/no reasoning.
  • The full-run results are lower than several smoke estimates, demonstrating why small-sample scores should not be used for release claims.

7. Risk and production-readiness assessment

Dimension

Status

Evidence / gap

Training pipeline

Green

Resumable run completed; artifacts synchronized

Instruction following

Amber

Answer-oriented behavior learned, but inconsistent

Language fluency

Amber

Readable short-form output with repetition and drift

Factual reliability

Red

Hallucinated sources and claims observed

Math / reasoning

Red

Basic discount problem failed

Benchmark strength

Amber–Red

41.68% mean; several tasks near baseline

Safety alignment

Red

No documented safety preference tuning or red-team suite

Data governance

Amber–Red

Public mixture; provenance, licensing, and decontamination incomplete

Serving stack

Amber

Weights exist; API, batching, quotas, monitoring still required

High-stakes use

Red

Not suitable without retrieval, guardrails, and human review

Production definition

A model becomes usable by people only after the weights are wrapped in a reliable product system. For W-1.1 this means a versioned inference service, tokenizer/config packaging, prompt template, output controls, authentication, rate limits, logging, latency tests, abuse safeguards, evaluation gates, rollback, and clear user-facing limitations.

Recommended release label W-1.1 Instruct v1 — experimental research preview. Do not claim GPT-2 parity or general-answer accuracy until direct, reproducible comparisons and safety evaluations are complete.

8. Recommended next phase

Priority

Action

Success criterion

P0

Freeze and hash the final checkpoint, tokenizer, config, metrics, and dataset manifest

Reproducible release bundle with SHA-256 checksums

P0

Create a decontaminated evaluation set not represented in training

Reliable generalization estimate

P0

Build a 200–500 prompt human evaluation across factuality, math, code, safety, and refusal

Scored rubric with error taxonomy

P1

Clean and rebalance instruction data; reduce low-quality or duplicated OpenOrca dominance

Higher validation quality and fewer repeated patterns

P1

Add targeted supervised data for arithmetic, concise QA, grounding, and refusals

Improvement on held-out targeted tests

P1

Run preference tuning only after SFT data quality is stable

Better instruction adherence without benchmark regression

P2

Package an inference API with deterministic mode, sampling controls, monitoring, and quotas

Stable pilot endpoint

P2

Quantize and profile on target hardware

Measured memory, latency, and quality trade-off

P2

Publish a model card and known-limitations statement

Responsible research release

Suggested acceptance gates

  • No regression on the seven full benchmarks; statistically meaningful improvement on at least three.
  • ≥90% format compliance on a held-out instruction suite.
  • Substantial reduction in arithmetic and factual error rates in human review.
  • Safety and abuse tests documented, including refusal behavior and leakage checks.
  • End-to-end serving tests cover load, latency, failures, logging, rollback, and cost.

Appendix A. Artifact inventory

Artifact

Purpose

Location / status

Jhelum Labs 125M-instruct-v1.safetensors

Final instruction-tuned weights

Google Drive project output; ~565.6 MiB

best.safetensors

Best periodic checkpoint

Instruction output folder

config.json

Architecture and tokenizer configuration

Packaged with checkpoints

tokenizer.json

32k BPE tokenizer

Base project / instruction bundle

instruct-metrics.json

Training and validation history

Instruction output folder

_TRAINING_COMPLETE.json

Completion marker and final metadata

Instruction output folder

train/validation/test JSONL

Raw 300k instruction corpus splits

W-1.1-project-instruct/dataset

tokenized binaries

1,024-token inputs and response-masked labels

Persistent Modal Volume

jhelum-labs-1.1-instruct-full-results.json

Full benchmark output

/vol/evaluation/

Appendix B. Full benchmark record

Task

Raw acc.

Raw SE

Norm. acc.

Norm. SE

ARC Easy

0.447811

0.010204

0.406987

0.010081

ARC Challenge

0.202218

0.011737

0.244027

0.012551

HellaSwag

0.274547

0.004454

0.283310

0.004497

PIQA

0.601741

0.011422

0.589771

0.011476

WinoGrande

0.504341

0.014052

—

—

BoolQ

0.592966

0.008593

—

—

OpenBookQA

0.176000

0.017048

0.296000

0.020435

Benchmark runtime: 2.47 minutes. Results file: /vol/evaluation/jhelum-labs-1.1-instruct-full-results.json.

Appendix C. Research conclusion

The W-1.1 instruction experiment is technically successful: a custom 123.7M-parameter pretrained model was converted into an answer-oriented checkpoint through a reproducible H100 workflow, and the final artifacts were preserved. The evidence does not support calling it a fully accurate or general production GPT. Its main value today is as a functioning research platform for data curation, fine-tuning, evaluation, quantization, and serving experiments. The most productive next investment is not simply more epochs; it is cleaner targeted data, uncontaminated evaluation, and a guarded inference system.

Source: User-supplied W-1.1 preprocessing, pretraining, instruction-training, generation, and benchmark logs dated 19–21 August 2026. All numerical claims in this report are derived from those project records.

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