textilelabs/Loom-Weave-2-Flash

Loom Weave 2 Flash

19.9M parameters · 512 context · Textile Labs

The same architecture and corpus as Loom Spark 2, trained for two hours instead of one. Twice the optimiser steps, one variable changed.

Trained from scratch on a 2013 desktop CPU — randomly initialised weights, nothing fine-tuned from a pretrained base.

who are you              →  Loom, a small model from Textile Labs.
WHO ARE YOU???           →  Loom, a small model from Textile Labs.
what is my sisters name  →  I can't know that unless you tell me.
i had a rough day        →  That sounds heavy. Want to talk about it?

What the second hour bought

Identical battery, identical prompts, one variable — training time.

	Spark 1.8	Spark 2 (1h)	Weave 2 Flash (2h)
offline <lookup> leak	16/30 · 53%	0/30	0/30
clean single online lookup	8/10	10/10	10/10
identity correct	—	12/12	12/12
identity under CAPS / typos / filler	not trained for	6/6	5/6
admits an unknowable personal fact	—	4/8	6/8
answers from a supplied <result>	—	2/5	3/5
says the result doesn't contain it	—	0/4	0/4
self-termination without a Modelfile	needed one	12/12	12/12
validation loss · accuracy	—	2.69 · 0.536	2.25 · 0.589

809 steps → 1,645 steps. Calibration and grounded reading both improved; loss and accuracy improved clearly.

The one thing more training did not fix

says the result doesn't contain it stayed at 0/4. Twice the training, identical zero.

That is worth publishing rather than hiding, because it rules something out. Nearly a third of the training corpus — 30,000 human-written examples — is exactly this behaviour, and 3.3M additional tokens moved it not at all, while every neighbouring metric moved.

So this is not under-training. The likely reason: saying "the result doesn't say" requires detecting an absence — reading the whole result and concluding the answer is not in it. That is a harder computation than extracting a span that is present, and at 20M parameters it appears to be out of reach. By contrast unknowable (6/8) only needs to notice "my" or "I" in the question.

Practical consequence: if you feed this model a result, it will answer from it whether or not the answer is there. Validate the output. Treat the retrieved <result> as the trustworthy part and the model's summary of it as unreliable.

It also has almost no world knowledge. With tools off it declines factual questions, which is intended behaviour rather than a fault.

Two modes

<tools:off> (default) — conversational. Identity, limits, warmth, brevity. No harness needed.

<tools:on> — emits <lookup>query</lookup> and stops. Your harness runs the lookup and continues with a <result> block:

<tools:on>
<user>
what is the capital of Peru
<|eot|>
<loom>
<lookup>what is the capital of Peru</lookup><|eot|>
<result>
Lima is the capital and largest city of Peru.
<|eot|>
<loom>

The persona slice was trained entirely under tools:off, so identity questions asked with tools on will often be turned into a lookup. Keep tools off for chat.

Usage — the harness

harness.py in this repo runs the lookup Loom asks for and feeds the result back. Wikipedia is used because it is free and needs no key — swap the search() function for anything else; the contract is text in, text out.

python3 harness.py "who wrote Dracula"          # with lookups
python3 harness.py                              # interactive
python3 harness.py --no-tools "who are you"     # chat only

Three things any harness for this model needs:

• Never feed a failed lookup back as a <result>. The model will earnestly try to answer from the error text. Fail loudly instead — harness.py does.
• Wikipedia returns 403 without a descriptive User-Agent.
• macOS system Python often needs certifi for TLS.

Usage — Ollama

ollama run hf.co/textilelabs/Loom-Weave-2-Flash "who are you"
# Loom, a small model from Textile Labs.

Ollama reads the template and params files in this repo — nothing to set up. The template defaults to tools:off. To build locally: ollama create loom-weave-2-flash -f Modelfile.

Usage — transformers

import torch
from transformers import AutoTokenizer, AutoModelForCausalLM

tok = AutoTokenizer.from_pretrained("textilelabs/Loom-Weave-2-Flash")
model = AutoModelForCausalLM.from_pretrained("textilelabs/Loom-Weave-2-Flash").eval()
eot = tok.convert_tokens_to_ids("<|eot|>")

def ask(message, tools=False):
    p = f"<tools:{'on' if tools else 'off'}>\n<user>\n{message}\n<|eot|>\n<loom>\n"
    ids = tok(p, return_tensors="pt", add_special_tokens=False).input_ids
    with torch.no_grad():
        out = model.generate(ids, max_new_tokens=64, do_sample=False, eos_token_id=eot,
                             pad_token_id=tok.convert_tokens_to_ids("<|pad|>"))[0]
    return tok.decode(out[ids.shape[1]:], skip_special_tokens=True).strip()

ask("who are you")   # -> 'Loom, a small model from Textile Labs.'

Prompt format is exact: <tools:off>\n<user>\n{message}\n<|eot|>\n<loom>\n.

Which one should I use?

This one, unless you specifically want the one-hour model. It is better on calibration, grounded reading, and both loss metrics, and marginally worse on a single identity probe. Spark 2 exists as the one-hour tier and as the control in this comparison.

Files

config.json / model.safetensors           the model
tokenizer.json / tokenizer_config.json    custom BPE tokenizer, 4,096 tokens
loom-weave-2-flash-f16.gguf               40MB, for Ollama / llama.cpp
harness.py                                runnable harness — runs lookups, feeds results back
template / params                         read automatically by `ollama run hf.co/...`
Modelfile                                 for building locally
ATTRIBUTION.md                            required credits for the training corpora

Training data

Openly licensed corpora of real human text, plus a persona curriculum written for Loom. See ATTRIBUTION.md — several of these licences require credit.

slice	source
grounded reading, and "the result doesn't say"	SQuAD 2.0 (CC BY-SA 4.0)
when to reach for a tool	MASSIVE (CC BY 4.0) · CLINC150 (CC BY 3.0)
instruction following	databricks-dolly-15k (CC BY-SA 3.0)
multi-turn dialogue structure	OpenAssistant OASST1 (Apache 2.0)
identity, limits, warmth, brevity	Textile Labs — written for Loom

~11.4M tokens, 43% multi-turn. Validation is a held-out split of the same corpora.

License

Model: MIT. Training data retains its original licences and attribution.