lfm2.5-audio-tool-aware-v4

LFM2.5-Audio-1.5B — Tool-Aware Fine-Tune (v4)

Full fine-tune of LiquidAI/LFM2.5-Audio-1.5B that handles both turns of a tool-augmented voice flow plus chitchat and refusals.

Results vs v3

Held-out eval, 120 rows × 30 per class:

Novel-facts narration (60 OOD tool results never in training): 95% faithful / 0% memorized.

What changed in v4

1. tool_miss ratio bumped 14% → 28%.
2. Hard-negative tools_listed: 60% of tool_miss rows include a semantically adjacent tool (e.g. scenario=traffic with maps listed but not traffic).
3. 19 diversified refusal templates (v3 had 5; v3 memorized phrasings).
4. Explicit "if not listed, decline" clause in the instruction line.
5. Tighter non_tool filter — drops DailyDialog context-fragments ("Spring .", "About 6:00 .").

Two-turn flow

# turn 1 — model emits "let me check the weather." and stops
# coordinator runs the weather tool, gets "Weather in Tokyo: 72°F, sunny."
await ctrl.<audio_node>.set_context("Weather in Tokyo: 72°F, sunny.")
# turn 2 — re-feed same user audio; model narrates ("it's 72 and sunny in tokyo.")

Training recipe

• Base: LiquidAI/LFM2.5-Audio-1.5B, full bf16 finetune
• Hardware: 2× RTX 4090
• 3000 train + 400 eval, mix 22/24/28/26 (tool_match / tool_result_speak / tool_miss / non_tool)
• bs=2/GPU × 2 GPUs × 1120 steps (~1.5 epochs)
• lr 5e-5, cosine + 100 warmup, ctx=512
• PYTORCH_CUDA_ALLOC_CONF=expandable_segments:True
• Final val_loss = 0.89

Recipe + scripts: matbee/lfm2-tool-aware-dataset-v4.

Known limitations

• 4/30 tool_match failures use a refusal template when the tool IS listed — refusal signal slightly over-corrected vs v3. v4.1 will rebalance.
• 3/60 novel-facts mixed verdicts on iot_lights and weather.

Usage

import torch
from liquid_audio import LFM2AudioModel, LFM2AudioProcessor

processor = LFM2AudioProcessor.from_pretrained("matbee/lfm2.5-audio-tool-aware-v4", device="cuda")
model = LFM2AudioModel.from_pretrained(
    "matbee/lfm2.5-audio-tool-aware-v4", device="cuda", dtype=torch.bfloat16
).eval()

Predecessors

• matbee/lfm2.5-audio-tool-aware-v1 — initial; mastered turn 1, regressed on turn 2 narration.
• matbee/lfm2.5-audio-tool-aware-v2 — added tool_result_speak; 100% ack + 20/20 narration on its eval.
• v3 (not published) — added distilled non_tool class; fixed narration but classifier-boundary regressed.
• v4 (this release) — fixes tool_miss/non_tool boundary via hard negatives + diversified refusals.

License

Inherited from base: LFM Open License v1.0.