When AI Starts Paying AI: The Birth of the Machine Economy

7 min read Original article ↗

Dmitrii Mingalev

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AI agents are starting to not just call tools, but also pay them micro-fees over APIs. Developers can earn from small, well-defined microservices with pay-per-use pricing instead of building full SaaS companies.

Today, most AI tools still feel like apps: you open a UI, paste some text, click a button, and hope for a good answer.

But something quietly shifted.

AI systems are getting the ability not just to call tools, but to pay for them.
Not “subscriptions for humans”, but actual micro-payments from one service to another — in real time, without a human in the loop for every operation.

This is the beginning of the machine economy: a world where agents pay other services for work. And that changes what it means to be a developer.

[ AI as app ] --uses--> [ Tools ]
↓ transforms into
[ AI as economic agent ] --uses & pays--> [ Tools + Payments ]

The Pain: Building Useful Tools That Don’t Earn

If you’re a developer, this might sound familiar:

  • you build a neat internal script or SaaS toy,
  • people star it on GitHub, maybe use it in side projects,
  • but turning it into a real business is… painful.

You’d need:

  • onboarding, dashboards, authentication;
  • billing, invoices, refunds, taxes;
  • support, marketing, content.
[ Core function ]
|
v
[ Billing | Auth | Dashboard | Marketing | Support ]
= "Company overhead"

In other words, you must build a company, even if what you really have is just one great function that solves a clear problem:

  • clean some data,
  • extract entities,
  • classify something,
  • call a third-party API in a smart way.

Until recently, there was no good way for these small but valuable pieces of code to earn money just by being called by other software.

What Changed

Three things happened almost simultaneously:

  1. Agents learned to call tools
    Modern LLM-based agents can read tool specs (OpenAPI, JSON Schema, MCP) and call your service as part of solving a task — without you writing custom integrations for them.
  2. Infrastructure for pay-per-use matured
    It’s becoming easier to:
    - meter requests,
    - charge per call or per token,
    - handle payments programmatically via open payment standards like x402 and similar protocols.
  3. AI is getting spending power
    Once an agent has both a toolbox and a wallet, it can:
    - choose between several providers,
    - compare price, latency, and quality,
    - pay other services as part of its workflow.
    At that moment, it stops being just “software” and starts behaving like an economic actor.
[ Agents call tools ]   +   [ Pay-per-use infra ]   +   [ Agents with wallets ]
tools-as-API cheap metered usage autonomous spending

= emerging machine economy

What Does a World with AI Paying AI Look Like?

Imagine a task:

“Research our top 5 competitors and prepare a 10-slide presentation with key metrics and positioning.”

The human doesn’t stitch 10 tools together. They just submit this as a single request to an AI agent.

Behind the scenes, the agent:
- breaks the task into steps;
- picks services it trusts for each step;
- pays them small fees to get work done;
- assembles and returns the final result.

The chain might look like this:

[ Human ]
|
v
[ AI agent ]
|
v
[ Data-gathering service ] (~$0.01 per company)
|
v
[ Analytics service ] (~$0.02 per analysis)
|
v
[ Presentation builder ] (~$0.05 per deck)
|
v
[ Human ]
  • Data gathering service
    The agent calls a web-scraping / enrichment API to collect basic info about competitors.
    A few cents per company.
  • Analytics / benchmarking service
    Another tool normalizes metrics, compares pricing, and produces a structured summary.
    A few more cents.
  • Presentation builder
    A service that takes the structured summary and turns it into slides with visuals and bullets, exportable to your favorite format.

Each of these services is built by different developers. Each gets paid per request, directly or via the platform that routes the calls.

For a human, this is just one request. But under the hood, a tiny economy is unfolding:

AI → AI → AI → result → human.

What Does This Mean for Developers?

If agents can pay other services, then a lot of existing code can become:

small, focused, paid building blocks in the machine economy.

Several shifts happen.

[ Old SaaS world ]           transforms into           [ Machine economy world ]

Users: humans Users: humans + AI agents

Focus: full product, dashboards Focus: one excellent function / microservice

Revenue: plans, subscriptions Revenue: per-call micropayments

Growth: marketing, sales Growth: being picked by agents (quality/price)

  1. Your users are agents
    A human might call your API a few times a month.
    An agent can call it thousands of times a day.
    If your tool:
    - solves the problem better than others,
    - is cheap,
    - works reliably,
    agents will keep using it again and again — without landing pages, ads, or Google Ads.
  2. Micropayments instead of a monolithic SaaS
    You don’t need to build a huge product with:
    - authentication,
    - pricing plans,
    - dashboards,
    - sales teams.
    Instead, you can:
    - write a microservice in 50–200 lines of code,
    - do one thing, but do it perfectly,
    - set a per-call price like $0.0005–$0.005,
    - plug in a payment protocol,
    - publish it in a marketplace or catalog.
    Small fees per request. Big money from scale and agent traffic.
  3. A market where quality and metrics decide
    Agents will choose tools based on:
    - price,
    - accuracy,
    - speed,
    - reputation (errors, uptime, reviews),
    not on how pretty your landing page is.
    You’re no longer competing with marketing and slide decks. You’re competing with the quality of your code and your service.

What Can Be Done Right Now?

A short checklist:

  1. Turn Your Tool into a Clean Building Block
    Pick one thing your tool does well.
    Rewrite or wrap it so that:
    - the input is well-defined and minimal,
    - the output is structured (JSON) and predictable,
    - error cases are explicit and informative.
  2. Describe It in Agent-Friendly Formats
    Describe your tool in a way that AI systems can understand and use:
    - MCP server,
    - OpenAPI,
    - JSON Schema,
    The easier it is to plug your service into a tool registry or an AI platform, the more likely it is to be reused in different workflows.
  3. Set Up a Simple Pay-Per-Use Model
    Create a straightforward model:
    - price per call or per unit of work,
    - clear limits,
    - clear error messages.
    Keep it simple and transparent — humans and agents both hate billing surprises.
  4. Show Up Where Agents Live
    Publish your tool wherever agents are active:
    - marketplaces,
    - tool catalogs,
    - agent platform ecosystems.
    You don’t control how your tool will be used, and that’s fine.
    The whole point is that agents can discover it, plug it into their own reasoning, and start sending you traffic when it fits.

What Is the Machine Economy Really Leading To?

The machine economy isn’t a sci-fi concept or a distant future. It’s a very practical shift that’s already starting: digital tools are beginning to pay other tools for specific tasks.

AI agents are becoming a new kind of client. They:

  • choose services based on price, speed, and quality,
  • pay for each service themselves,
  • assemble chains of microservices,
  • deliver a finished result back to the user.

For developers, this means a change in perspective:

You’re no longer building tools only for humans. You’re also building for AI agents that can independently decide, call, and pay for valuable actions.

So the main question becomes:

Is my tool ready for a world where AI pays AI for every unit of real value?

If the answer is “not yet”, then it’s a good moment to turn that GitHub side project into a paid building block of the machine economy.

Turn your side project
into a paid building block

[ 1 ] Make it agent-ready
[ 2 ] Make it pay-per-use
[ 3 ] Put it where agents can find it

Further reading on the machine economy and pay-per-use:

- x402: the internet-native payment protocol
- x402 overview in Coinbase docs
- Circle: enabling machine-to-machine micropayments with x402 and USDC