A field guide to building for agents
Opero · Vol. 2
October 2026
Agents already browse, research and buy on the web, through screens built for people. Four ideas for building the software they actually want, and the platform that does all four.
2,000+
products agent-ready
2.1B
agent calls a month
41s
to first paid call
Agent-ready with Opero
Ledgerline
Northwind
Halcyon
Acme Labs
Shoply
The field guide · 4 ideas
Four ideas for building software agents want.
Each one comes with proof from real agent traffic, and the part of Opero that does it for you.
Interfaces
Agents don’t click.
Every form, modal and CAPTCHA is a wall to a user that reads JSON. Give agents a contract instead of a screen, and they finish in seconds what a browser session never finishes at all.
How Opero does it
Proof
Browser
10 steps
API
3 calls
Discovery
Docs are the new homepage.
Agents decide whether to use you by reading, not browsing. A short llms.txt and honest OpenAPI descriptions are the first impression you make on your next million customers.
How Opero does it
Proof
llms.txt
GET /llms.txt
# Ledgerline
> Invoicing API built for agents.
## Sign up
POST /v1/accounts
## Core calls
- invoices.create
- invoices.send
Onboarding
Sign-up is an API call.
No email loop, no password reset, no onboarding tour. One request returns an account, a verified owner and a key scoped to exactly what the agent needs.
How Opero does it
Proof
Response
201 Created
POST /v1/accounts
account acct_7Qm2
owner maya@ledgerline.com
key ak_live_9f2c
scope invoices:write
cap $500 / day
Billing
Pricing follows the work.
Agents don’t take seats. They make calls, sometimes three a month and sometimes three million a day. Meter every one, cap spend per agent and hand back a receipt.
How Opero does it
Proof
Usage
Today
invoices.create 12,480 $24.96
invoices.send 9,112 $18.22
accounts.get 2,301 $0.00
total 23,893 $43.18
cap remaining $456.82
05 · The platform
Opero does all four, from one schema.
REST API
MCP server
CLI
llms.txt
Agent sign-up
Scoped keys
Per-call billing
Signed receipts
06 · The dashboard
See who’s calling your product.
ledgerline / traffic
Live
calls · 24h
+12% today
new agents
+38 today
p50 latency
−4ms today
billed today
+9% today
Calls by agent type · last 24h
New sign-ups
research-bot
Acme Labs · invoices:read
2s
buyer-07
Shoply · invoices:write
9s
ops-runner
Northwind · usage:read
14s
claw-agent
Maya L. · invoices:write
31s
cursor-dev
Ledgerline · keys:create
48s
recon-3
Halcyon · receipts:read
1m
View all 412 agents
08 · Pricing
Priced per call, like your users.
No seats, no minimums. Pay for the calls agents make.
calls free every month
per call after that
for failed or blocked calls
09 · From the blog
Notes from the agent economy.
Product
6 min read
Introducing Opero 2.0: make your product agent-ready in an afternoon
One schema in, an API, an MCP server, a CLI and machine-readable docs out. Plus agent sign-up and per-call billing.
Read post
Company
5 min read
Make something agents want
The next trillion users of the internet won’t be people. Here’s what changes when your best customer never opens a browser.
Read post
Customers
5 min read
How Ledgerline signed up 41,000 agents without a sales call
An invoicing tool, a weekend with Opero and a new kind of customer. Half of last quarter’s accounts were agents.
Read post
10 · Questions
Good to know.
Can’t find an answer? Our engineers reply within a working day.
Talk to an engineer
Do I need to rebuild my backend?
No. Point Opero at your existing API or OpenAPI spec and it generates the MCP server, CLI and docs on top. Legacy tools without an API can use one of our adapters.
