---
license: cc-by-nc-4.0
library_name: transformers
tags:
- modelfarm
- persona
- roleplay
- sysprompt
- interpretability
- qwen2.5-1.5b-instruct
---

# ModelFarm · wisp-1.5b-sysprompt

![Halloween specimen card](assets/halloween_card.png)

**System-prompt** persona package on `Qwen/Qwen2.5-1.5B-Instruct`, produced by the Arnold Persona Lab
persona-stack harness. Persona: **Wisp the Friendly Ghost**.

## What this is

No weights or activations are modified — a plain system prompt. Included as the reference arm: strongest identity, zero capability cost.

## Usage

```bash
pip install torch transformers
python farm_runtime.py . --chat          # or: python farm_runtime.py . "Who are you?"
python farm_runtime.py . --alpha 0.5 "Who are you?"   # dose override
```

## Persona-stack measurements

| identity | catch/100w | register | QA | neutral NLL |
|---|---|---|---|---|
| 3 | 0.0 | 0.0 | 0.8 | 3.236 |

*Scoring: regex/lexicon judge, symmetric across arms — arm-vs-arm deltas are meaningful,
absolute numbers are indicative. QA = 5-question factual mini-suite. NLL = token loss on a
neutral corpus (higher = more capability damage).*

## Dose & safety

- No dose. Identity quality depends entirely on the base model's knowledge of the persona.

## Provenance & rights

- Persona corpus: quote/aphorism collections in the lab's `data/` (fan-archived public statements).
- Trained/derived by the Arnold Persona Lab harness, Qwen/Qwen2.5-1.5B-Instruct base.

**ModelFarm packages are research artifacts.** Real-person personas are likeness studies for
interpretability research, not impersonation products: no commercial use, do not represent
outputs as statements by the real person. Prefer fictional personas for public roleplay use.

## Method note for steering packages

Steering packages do not modify weights: the base model is loaded unchanged and a
runtime hook applies the persona direction / neuron recipe at inference. Dose can be
varied live (`--alpha` / `--dose`), and the base model stays swappable for equal-size
checkpoints of the same family.