Voice AI applications are gaining popularity as advances in large language models (LLMs) enable more natural and accessible spoken interactions. Serving these applications requires accounting not only for what users say, but also for how they speak (e.g., speaking rate) and the conditions under which their audio is captured and transmitted (e.g., background noise and packet loss). However, existing LLM systems represent conversation context as a flat, growing sequence of messages, leaving voice-specific context implicit in the audio. As a result, they can generate responses that are poorly aligned with user preferences, degrade interaction quality under adverse environmental conditions, and incur high costs over long voice sessions. We present llmovoice, a context-management middleware that explicitly models voice context and orchestrates its use. At each turn, llmovoice constructs a bounded voice context from the current user input, relevant interaction history, and explicit paralinguistic and environmental states. It then uses the serving LLM to reason over this context and generate runtime directives that guide how the system responds. We evaluate llmovoice on real-world voice applications and benchmarks. It reduces speaking-rate alignment error by 52.4%, lowers the false-interruption rate from 46.0% to 0.9% under packet loss, and reduces model usage cost by 79.2%. For long sessions, llmovoice reduces per-turn cost by up to 24.9 times while retaining up to 98.7% of baseline answer quality.
Figures & tables
Figure 1. Overview of the LLM-over-voice serving pipeline.
Figure 2
Figure 4. System overview of llmovoice .
Figure 5. Context orchestrator maps the current states and runtime configuration to validated runtime directives.
Figure 6. Memory layout and context-window construction. The context projector uses vthreads and vpages to construct projected history under a context budget, selecting among audio, transcript, and summary representations.
Policy
FIR
Latency (ms)
Network cost ($/trace)
Fixed-500
46.0%
1286.1
0.003344
Static-Max
0.0%
4021.4
0
llmovoice
0.9%
1830.7
0.000695
Table 1. Turn-control results over ICASSP PLC traces.
Figure 7. Cost per turn versus conversation history length.