TacitVLA: Reasoning Vision-Language-Action Models Without Reasoning Latency
Textual reasoning before acting has improved vision-language-action (VLA) models, but at the cost of latency: every action conditioned on the reasoning text must wait for autoregressive decoding.

ProofPaper ↗
Key points
- We show that actions do not need to wait for or condition on the generated reasoning to benefit from it, because the reasoning supervision already improves the backbone representation.
- We introduce TacitVLA, a reasoning VLA whose action expert never attends to the reasoning it generates for the current call.
- On long-horizon tasks where the reasoning text also serves as episodic memory, it can generate each entry during action execution rather than before acting.
- We evaluate it in a controlled study on four benchmarks spanning manipulation and autonomous driving, memory and non-memory tasks: RoboMME, RMBench, LIBERO, and PhysicalAI-AV.
Sources (2)
- [1]TacitVLA: Reasoning Vision-Language-Action Models Without Reasoning LatencyHugging Face Daily Papers · Oct 13, 12:00 AM
Textual reasoning before acting has improved vision-language-action (VLA) models, but at the cost of latency: every action conditioned on the reasoning text must wait for autoregressive decoding.
We show that actions do not need to wait for or condition on the generated reasoning to benefit from it, because the reasoning supervision already improves the backbone representation.
- [2]TacitVLA: Reasoning Vision-Language-Action Models Without Reasoning LatencyarXiv (AI, ML, NLP, CV, robotics, multi-agent) · Oct 13, 01:09 AM · same content
Extractive summary: sentences quoted from the sources.
Before this
- Oct 12, 2026Listen Before Act: Audio-Conditioned Robot Manipulation with ListenVLA
- Oct 12, 2026AUGUstus: Autonomous Driving VLA Model with Unified Generation and Understanding
- Oct 11, 2026$Δ$ Flow Matching for Robot Foundation Models
- Oct 11, 2026Vision-Predictor-Action: Towards Efficient Embodied AI via Neuro-Symbolic JEPA Predictors
- Oct 11, 2026Exploring the Limits of Combinatorial Generalization in Embodied Manipulation
- Oct 10, 2026Verify, Act, Distill: Turning Test-Time Compute into Test-Time Adaptation for Vision-Language-Action Models