Harvey built the legal AI exam; Z.ai just passed 19% of it at about 15 cents a task
Z.ai's GLM-Legal passed 19 percent of Harvey LAB at about 15 cents a test, and Vals calls it the cheapest model in the top 10. The benchmark Harvey built to prove its product now prints the cost of competing with it.
Richard Tang · 3 min read
The biggest legal-AI news this week is a price. On October 12, Z.ai, the Chinese lab also known as Zhipu, released GLM-Legal, a legal agent built on its cheap GLM-5.3-Flash base 23. Independent evaluator Vals AI scored it 19 percent on Harvey LAB, the 1,250-task exam of law-firm work that Harvey$15.5B — Harvey, private, latest valuation $15.5B, the private company selling legal AI to the largest firms, built and open-sourced 13. A task passes only if every rubric criterion does, and Vals priced a full run at about 15 cents a test 13. The exam built to prove Harvey's product now prints the cost of competing with it.
The score tripled without a bigger model
The jump came from training, not scale. Z.ai put its lightweight base through legal mid-training and reinforcement learning across tens of thousands of legal task environments, re-tuning the agent harness, the runtime that manages context and tools, in lockstep with the model 2. The pass rate nearly tripled from the base model: seventh of 79 on Vals' board, ahead of Anthropic's$350B — Anthropic, private, latest valuation $350B Claude Fable 5 and OpenAI's$1.18T — OpenAI, private, latest valuation $1.18T GPT-6 Astra, behind Meta's+2.51% — Meta, up 2.51 percent today Muse Spark 1.2 at 25 percent 13.
The exam became a price list
Vals runs the held-out tasks with the internet off and prints cost beside score, calling GLM-Legal the cheapest model in the top 10 1. A benchmark built to prove a product has become the industry's comparison layer: the same Monday, Meta launched Muse Wonder with Harvey LAB numbers on its own charts, 13 percent for its largest model 5.
GLM-Legal sits at the floor of the Harvey LAB cost curve
- Estimate
Data
| Value | |
|---|---|
| GLM-Legal (Z.ai) (estimate) | $0.15/test |
| Muse Spark 1.2 (Meta) | $2.09/test |
| Kimi K3 (Moonshot) | $3.83/test |
| Gemini 4 Argon (Google) | $10.55/test |
| Claude Fable 5 (Anthropic) | $19.23/test |
| GPT-6 Astra (OpenAI) | $26.16/test |
Cheap was the easy part
That price carries an asterisk: Z.ai publishes no GLM-Legal rate card and grants access only by application, so 15 cents is Vals' arithmetic at GLM token rates 134. Throughput is the real trade, at 72 minutes a task on average 3. Google's Gemini 4 Argon finishes the same run in 44 4. A one-in-five pass rate means the model still fails most of the exam it was trained for. The price is observed; work leaving lawyers' desks is projection.
The money sits between the benchmark and the matter
Harvey's business runs the other way. It added more than $100 million of annual recurring revenue in a single quarter, with growth-equity stakes from Goldman Sachs+0.62% — Goldman Sachs, up 0.62 percent today and JPMorgan following in July 6. Its CEO told Nikkei it opens a Japan office in early 2027, targeting Japan's largest firms and corporate legal departments, with efficiency pressure coming for billable time 7. Firm AI chiefs are untroubled: Herbert Smith Freehills Kramer's chief AI officer told Law.com she would not call skyrocketing AI utilization concerning 8. If utilization keeps rising while the exam prints a cost floor, the spread between subscription revenue and inference cost has to land somewhere, and today it lands on the firms.
The bottleneck has moved off price onto reliability and workflow, and both sides are working that gap now. Z.ai is bolting GLM-Legal into AutoClaw, a desktop agent that returns contract edits as tracked changes in Word 9; Harvey owns the workflow layer its customers already run.
A 15-cent task does not make a 15-cent lawyer. Whoever sells the distance between the two first takes the seat revenue with it, and the capability just got cheap enough to learn on.
Deepdive
AI-generated from this story and its cited sources. Not investment advice.
