# Placard

> One-click ad marketplace for independent websites. A site owner, or an agent acting for them, gets an ad embed in one API call, verifies the domain, then chooses which advertisers may appear.

## Quickstart for agents
1. POST https://placard.blrbdigital.com/api/v1/links with JSON {"domain":"example.com"} (no auth). Save api_key (shown once) and publisher_id. Give claim_url to the human owner.
2. Put embed.script in the site's HTML where the ad should render.
3. POST https://placard.blrbdigital.com/api/v1/publishers/{publisher_id}/verify with Authorization: Bearer {api_key}. Verification passes if the homepage contains the embed tag, the meta tag <meta name="placard-verification" content="{publisher_id}">, /.well-known/placard.txt contains the id, or DNS TXT placard-verification={publisher_id} exists.
4. GET https://placard.blrbdigital.com/api/v1/marketplace, then PUT https://placard.blrbdigital.com/api/v1/publishers/{publisher_id}/advertisers {"advertiser_ids":[...]} to choose advertisers. Confirm choices with the human owner.

## Reference
- OpenAPI: https://placard.blrbdigital.com/openapi.json
- Docs: https://placard.blrbdigital.com/agents