Working paper / 2026
Conversational AI LLM Bench
Abstract
We define conversational AI LLMs as the language models at the center of cascaded voice pipelines, between speech recognition and speech synthesis, that return a first token within one second: a median time to first token of 1,000 ms or less. The Conversational AI LLM Bench (CALLM) benchmarks this category. Each model operates every agent of a multi-agent front desk in healthcare, legal, and customer support, with production-length prompts, executable tools, and per-call database state. A simulated caller pursues a locked task over a simulated phone line, so the model receives only what a speech recognizer would have transcribed, errors included. A deterministic verifier scores tool calls, handoffs, and final database state; pass@1 and pass5 measure single-attempt capability and five-attempt reliability.
Clone the repository, point a model at an industry pack, and reproduce the evaluation environment.
CALLM groups its tasks into healthcare, legal, and customer-support suites. Each suite is a complete company: a multi-agent graph, specialist prompts, domain tools, a seeded database, and locked callers.
The company stays the same for every model. Only the LLM running its agents changes, so a gap between two rows is a gap between two models, not between two setups.
Dermatology front desk across seven specialists: access, identity, scheduling, coverage, cosmetic quotes, billing, and clinical triage.
Straus Dermatology
Plaintiff-firm intake under conflict-before-facts, no legal advice, and attorney-only declines.
Halverson & Reed
Retail support behind an order-bound identity gate: delivery, returns, TechCrew, membership, and an ungated fraud desk.
Kestrel Electronics