coconut — TRM-SVFT: recursive steering adapters in a frozen LLM

Train an LLM to reason without words. Instead of generating chain-of-thought tokens, the model thinks in continuous vectors inside its own layers.

Two papers motivate this:

• COCONUT showed a language model can reason in a continuous latent space — feeding its own hidden state back in as the next "token" — instead of reasoning out loud in chain-of-thought text.
• TRM (Tiny Recursive Model) showed a tiny network can beat much bigger ones on hard puzzles by recursively refining its answer: run the same small block many times over a scratchpad state and an answer state, instead of one big forward pass.

This repo combines the two ideas. Take a small frozen math model (Qwen3-0.6B-Math-Expert). Give some of its layers a small add-on module that, at each token, thinks for a few recursive steps TRM-style and then nudges what that layer outputs. The base model never changes. Only the add-ons learn, trained on grade-school math word problems (GSM8k), graded only on the final answer.

Did it work?

Partially. It learned math a bit better than chance, then overfit.

Peak accuracy on a small GSM8k subset (84 questions, greedy eval):

model	eval/acc (peak)
base model, no training	0.00 (0/84)
TRM-SVFT, canonical run trmsvft-qwen3-0.6b_20251105-185222, epoch 15	0.095 (8/84)
same run, epochs 16–28	collapses to 0.01–0.04 as train loss → 3e-5

So: 0% → ~10% peak, then it memorizes the train set. Loss kept falling while accuracy collapsed, classic overfit. Details in mjc_research_journal.md and outputs/*/terminal.log. An earlier hybrid run peaked at 0.205 on a similar eval, but it mixed other changes so treat it as a hint, not a result.

How it works (pseudocode)

Before: a plain SVFT/LoRA-style adapter. Each adapted frozen layer gets a rank-r SVD decomposition, and training only rescales the singular values:

# frozen decomposition of an adapted Qwen matrix
W ≈ U @ diag(S) @ V.T + W_res        # U, S, V, W_res all frozen

# a normal adapter: one shot, no state
scale ← head(x @ V)                  # tiny learned vector
y ← frozen_linear(x) + apply_svd_adapter(x, U, transform(S, scale), V, W_res)

After: TRM recursion inside the adapter. The singular-value scale is no longer computed in one shot — it comes from a small recurrent state that is refined over several weight-shared cycles (canonical version, commit 2c99374):

xV ← x @ V                          # project layer input into rank-r SVD space
zL ← cache.zL or learned_zL         # two latent states, b r
zH ← cache.zH or learned_zH

xV ← fold_sequence_into_batch(xV)   # canonical code treats token positions independently
zL, zH ← repeat_per_token(zL, zH)

def recurse(xV, zL, zH):
    for _ in range(l_cycles):
        zL ← L_net(zL, xV + zH)     # L_net: small weight-shared transformer block
    zH ← L_net(zH, zL)
    return zL, zH

with no_grad():
    for _ in range(h_cycles - 1):
        zL, zH ← recurse(xV, zL, zH)   # early cycles detached
zL, zH ← recurse(xV, zL, zH)           # only the final cycle gets gradients

scale ← output_head(zH)
S_eff ← transform(S, scale)
y ← frozen_linear(x) + apply_svd_adapter(x, U, S_eff, V, W_res)
cache.zL, cache.zH ← last_token(zL, zH)   # persists across autoregressive steps

Properties worth knowing:

• zL/zH live in the adapter rank (64–128), not the 2560-dim residual stream.
• One shared L_net is reused across all cycles and all adapted layers.
• The adapter modifies the frozen layer's output directly, not a side channel.
• Trained only on answer tokens.

---

Messy notes below — legacy / WIP material, read with care

Everything from here down is rough working notes and leftovers from older branches. Parts may not apply to the TRM-SVFT branch above.

Full experiment log: mjc_research_journal.md.

Branch map

branch	what it is	did it work?
master	TRM-SVFT recursive steering adapters (this)	partially: 0% → ~10% peak, then overfits
try_seq_vcr	latent-token COCONUT variant (the "seq-vcr" branch)	did not work (per notes)
wip-trm-seq	newest WIP: recursion over the whole sequence instead of per-token	self-labeled "wrong track" in its own commit message; kept for reference

Run

Configs and run targets may lag the code.

just install          # uv: flash-attn, pytorch, etc.
uv run scripts/check_gpu.py
just coconut-svft     # train TRM-SVFT on GSM8k
just coconut-svft-eval

Old readme: COCONUT experiments (older branches)

Code for the paper "Training Large Language Model to Reason in a Continuous Latent Space".

LLMs usually reason by producing chain-of-thought. But the most efficient part of the language might be the text it generates. Humans instead reason in a latent space, so why can't we get AI to do the same? If we can, we might be able to learn a super language, plan and more.

The COCONUT paper solves this. I gave this my own shot, using SFT with tensors instead of LoRA.

Setup

just install
uv run scripts/check_gpu.py

Results

ICOCONUT PROSOCIAL

Same method as the original paper except with PROSOCIAL instead of GSM8k. More info in the research journal.

Eval commands

# evaluate GSM8k
just eval gsm_icoconut
just eval gsm_coconut
just eval gsm_cot

# evaluate prosocial
just eval prosocial_icoconut
just eval prosocial_coconut
just eval prosocial_cot

Training commands

# TRAININGS
# gsm8k runs
uv run coconut.py gsm_coconut.yaml
uv run coconut.py gsm_icoconut.yaml
uv run coconut.py gsm_cot.yaml

# prosocial runs
uv run coconut.py prosocial_coconut.yaml
uv run coconut.py prosocial_icoconut.yaml
uv run coconut.py prosocial_cot.yaml