# Build a company list: agent skill

Company list builder API for an agent: it sends filters such as industry, size, country or technology to a catalog endpoint and reads company name, domain and industry back. Several providers sell the call, so the agent tries the cheapest first. You pay per call, and a failed call costs nothing.

## When it starts

- find software companies in the US with 50 to 200 employees
- build a list of companies that use Stripe
- give me 100 fintech companies in Germany

## What it asks for

- Industry, size, country or technology filters, as many as the user has
- How many companies to return

## How it runs

- looot discover finds the endpoint
- looot inspect shows the price and the input schema
- looot run executes it, billed per call
- Endpoints in order: theirstack-companies-search, fullenrich-api-company-search, thecompaniesapi-companies-post, people-data-labs-company-search-get, aviato-company-search

## What comes back

- Company name and domain
- Industry and country
- Employee count
- Matching technologies and jobs
- LinkedIn page

## Answer rule

Return a table of name, domain, country and employee count, and say how many matched in total.

## Install

Save the skill file as /agent-skills/company-list-builder/SKILL.md, or tell your agent: set up looot, then use /agent-skills/company-list-builder/SKILL.md.

## Difficulty

intermediate

## How do I build a list of companies by industry and size?

Describe the segment to your agent, for example software firms in the US with 50 to 200 employees. It picks a provider that supports those filters, runs the search with a limit and returns a table of companies.

## Can I find companies that use a specific technology?

Yes, with the providers that filter by tech stack. One of them also filters by hiring signals, so you can find firms that use a tool and are hiring for it.

## How many companies can one call return?

It depends on the provider. One caps a page at 25 companies, another at 62 through looot, and each result is billed. Your agent pages through the results until it has the number you asked for.

## What happens after the list?

The list is rows of companies with domains. Enrich them with company data, look up the email format, then find the people. Each step is its own call and its own price.

## Is the list complete?

No provider covers every company. Coverage is better for larger firms and in the US. Compare the first page from two providers before you commit to one.

## How much does one search cost?

You pay per call, and the price depends on the provider your agent picks. This page reads the cheapest live price from the catalog and shows no number when the catalog is unreachable.