The frontier model field guide: what you actually pay per million tokens
Context windows, list prices, latency under load and the lock-in clauses nobody reads. I ran the same twelve-task suite across nine flagship models.
Issue No. 14 · The Business AI Beat
Eighteen months of demos have finally given way to procurement, invoices and postmortems. I spent the last quarter inside eleven deployments — here is what actually survived contact with a P&L.
Two Novembers ago I sat in a boardroom while a vendor promised that an agent would "own" a client’s accounts-payable function by spring. It did not. What it did do — and this is the part nobody puts on a slide — was reduce a nine-step invoice exception workflow to three, and cut the median handling time from eleven minutes to four. The finance director called that a failure for a quarter, then quietly renewed.
That gap between the pitch and the payoff is the whole beat now. The frontier labs ship a new flagship roughly every eleven weeks; the interesting question stopped being which model wins some time in 2025. It is now: what does inference cost you at volume, how much of your engineering week is spent babysitting retries, and what happens to your pricing when your vendor raises output-token rates by forty per cent with thirty days’ notice?
I test with my own money and my own logs. Every claim in this issue comes with a number attached, or it does not run. Where I have not tested something myself, I say so. And where a vendor refused to give me a straight answer on per-seat versus per-outcome pricing — which happened three times this quarter — I say that too.
In this issue — five dispatches
Context windows, list prices, latency under load and the lock-in clauses nobody reads. I ran the same twelve-task suite across nine flagship models.
LangGraph, the OpenAI Agents SDK, CrewAI, Google ADK and Pydantic AI, judged on the only metric that matters: what happens on step fourteen.
Per-resolution support, per-matter legal review, per-lead outbound. I priced four outcome-billed vendors against the headcount they claim to replace.
Five platforms, one identical eleven-step workflow, and a monthly bill that ranged from £0 to £1,940. The spread is not about features.
Nobody demos an LLM proxy. But routing, observability and eval tooling are where the last three deployments I reviewed were won or lost.
Standfirst — How this desk works
Every piece on this site starts from a live workload. For model coverage that means a fixed suite of twelve tasks — four extraction, three long-context summarisation, two code-repair, two tool-calling chains and one adversarial refusal test — run at temperature 0.2, five times each, from a London region, on a weekday morning when the shared endpoints are busiest. Cherry-picked 3 a.m. latency numbers are marketing, not measurement.
For platform coverage I build the same eleven-step workflow every time: webhook in, enrichment lookup, conditional branch, LLM classification, CRM write, Slack notification, error handler, retry, dead-letter queue, daily digest, audit log. It is deliberately mundane. Mundane is what companies run.
I publish list prices with the date I checked them, because they move. I flag when a vendor has given me trial credits — it has happened twice and both times I said so in the piece. And when I get something wrong, the correction sits at the top of the article with the original text struck through, not quietly patched at 2 a.m.
On independence
viblyhappybundle.homes takes no vendor sponsorship, no affiliate commission and no paid placement. The publication is funded by reader subscriptions and a small consulting practice that never advises on tools covered in the same quarter. If that changes, it will be disclosed here first, in this section, in this typeface.