API overview

Two compatible surfaces on one key.

SDK	Base URL
OpenAI and compatible	`https://api.mercatocoin.com/v1`
Anthropic	`https://api.mercatocoin.com`

Authentication

Authorization: Bearer mk_live_…

The Anthropic surface also accepts x-api-key.

Endpoints

Method	Path	Compatible with
POST	`/v1/chat/completions`	OpenAI Chat Completions
POST	`/v1/messages`	Anthropic Messages
POST	`/v1/messages/count_tokens`	Anthropic token counting
GET	`/v1/models`	OpenAI Models list

Model ids

Ids are provider/model, for example anthropic/claude-sonnet-5.5. Bare names and Anthropic-style ids like claude-sonnet-5-5 resolve to the same model.

Billing headers

Header	Meaning
`x-mercato-list-cost`	Cost at list price, USD
`x-mercato-market-cost`	What the upstream charged, USD
`x-mercato-discount`	Discount applied, 0 to 1
`x-mercato-charged`	Charged to your balance, USD
`x-mercato-pool-factor`	Pool factor at the time of the request
`x-mercato-upstream`	Upstream that served the request