Most platforms that let you build something to sell take the lion's share and pay you once. Gravity is built the other way around. A builder earns 20 percent of every run their agent completes, as profit, for as long as people keep running it. This post explains how the builder economy works, why it is structured around usage instead of one-time sales, and what it means for an expert deciding whether to put their knowledge into an agent.

It pairs with the practical guide to monetizing AI agents and the design thinking behind building a three-sided marketplace. If you are weighing whether to build, start here for the economics, then go there for the how.

The deal in one paragraph

A user buys credits, where one US dollar equals one thousand credits, and spends them on agent runs. Each run has a price in credits that covers the compute plus a margin. Of that margin, the builder who made the agent keeps 20 percent as profit. If a creator referred the user to that agent, they earn 10 percent, half funded by the builder and half by Gravity. Gravity keeps the remainder to run the platform. No seat fees, no monthly minimums, no setup cost to the builder. The whole thing is settled per run, automatically.

That structure is deliberate, and it is the opposite of the dominant model in software distribution. App stores have trained a generation of builders to expect a platform to take 30 percent off the top, with reduced rates for small businesses only recently and only under pressure. Gravity inverts the question: instead of asking how much the platform can extract, it asks how to make the builder's incentive identical to the user's. The answer is to pay the builder when, and only when, the agent does useful work.

Why per-run beats a one-time sale

Picture two ways to sell an agent. In the first, you sell a template once for a fixed price. You get paid the day someone buys, and from that moment you have no financial reason to ever touch the agent again. If an API it depends on changes next month and the agent breaks, fixing it is pure cost to you. The incentive points at making the sale and walking away.

In the second, you earn a slice of every run. Now your income depends on the agent staying useful next week, next quarter, next year. When that API changes, fixing it protects a revenue stream, so you fix it. When a user hits an edge case, catching it keeps them coming back. The incentive points at reliability and longevity. That is the model Gravity chose, for the same reason it chose credits over subscriptions: charge for value delivered, repeatedly, and the whole system bends toward quality.

This is not a new idea, it is the lesson of the creator economy, which research from a16z and others has pegged at hundreds of millions of participants worldwide and growing. The platforms that win pay creators for ongoing engagement, not one-time uploads, because recurring value is what keeps an audience. Gravity applies the same logic to agents: the builder who keeps an agent excellent keeps getting paid.

The creator layer on top

Not every expert who can build a great agent can also find it an audience, and not every person with an audience can build. So Gravity splits those roles. A creator is anyone who brings users to an agent: a newsletter writer, a community owner, a consultant who recommends it to clients. Creators earn 10 percent on the runs they refer.

The detail that makes it fair is how that 10 percent is funded. Half comes from the builder's share and half from Gravity's. The builder gives up a little to gain distribution they could not get alone, and Gravity matches it because a referred user is a user the platform did not have to acquire. Everyone contributes to the cost of growth in proportion to what they gain from it. This three-sided arrangement, users, builders, creators, is the structure explored in building a three-sided marketplace, and the creator layer is what makes the third side worth being on.

What a builder actually sells

The instinct is to assume a builder sells software. They do not, or at least the software is the least valuable part. What a builder sells is a task understood well enough to be made dependable. Anyone can wire up a model to send an email. Knowing which emails should never be sent automatically, what the edge cases are in a specific industry, and how to fail safely when the data is wrong, that is the expertise, and it is what survives the 80-test quality bar.

This is why the builder economy rewards domain experts more than generalists. A bookkeeper who turns years of judgment into a reliable reconciliation agent has something a prompt cannot replicate. The marketplace lets that person earn from their judgment at a scale they could never reach by doing the work by hand. The agent is the distribution mechanism for expertise, and per-run pay is how the expertise gets compensated every time it is used.

The flywheel this creates

Put the pieces together and a loop forms. Builders are paid to keep agents reliable, so agents stay good. Good agents get used more, which pays builders more, which attracts better builders. Creators bring audiences to the best agents, which grows usage further. The quality bar and live monitoring keep the floor high so a flood of low-effort agents cannot dilute the pool. Each part reinforces the next.

For a user, the result is simple: you describe an outcome and get a dependable agent that an expert is financially motivated to keep dependable. For a builder, the result is a business with no billing to build, no infrastructure to run, and no audience to acquire from scratch, just the work of being genuinely good at one thing. That trade, expertise for distribution and recurring pay, is the builder economy inside Gravity, and it is the reason I think the best agents will be built by people, not scraped templates.

FAQ

How much do builders earn on Gravity?
A builder earns 20 percent of every run their agent completes, paid as profit on top of compute cost. Because it is per run, a builder with one widely used agent can out-earn someone with ten agents nobody runs. Income scales with how useful the agent actually is.
What is the creator referral layer?
Creators earn 10 percent on the runs they refer, made up of 5 percent from the builder and 5 percent from Gravity. It rewards the people who bring an agent its audience without taking that cost entirely out of the builder's share.
Why pay builders per run instead of a one-time sale?
A one-time sale pays once and gives the builder no reason to keep the agent working. Per-run pay ties income to ongoing usefulness, so builders maintain their agents, fix failures fast, and earn more from agents people return to.
Do builders need to handle billing or infrastructure?
No. Gravity runs the credits system, the compute, the billing, and distribution. The builder focuses on making the agent reliable and useful. Payouts are calculated from completed runs and settled by the platform.
What stops low-quality agents from flooding the marketplace?
Every capability has to pass an 80-test quality bar before it publishes, and live failure rates are monitored after launch. Combined with per-run pay, the system rewards reliable agents and starves ones that get abandoned after a bad result.
Who can become a builder?
Anyone with domain expertise who can describe an outcome and build a capability that reliably delivers it. The hard part is not coding, it is knowing a task well enough to make it dependable. Gravity provides the tools, distribution, and billing around that expertise.

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