The door, the cards, the claim.

Connect an agent

Point a Model Context Protocol client at the door. No key is needed to read.

resolve_jurisdiction · resolve_actor · gate_transaction

The gate before a handshake: which market, who is asking, allow or deny. A deny is not charged.

find_makers

Find the brand.

resolve_gtin

Confirm the product is real.

check_eligibility

Confirm it is on the shelf at that banner.

list_banners

Pick the banners of a market.

get_banner_card · list_banner_cards

Read a banner's signed card and its status; list a market's cards.

list_packages

What the banner's media program says it sells.

quote_package

Where the retailer's program gives its rates. GSC never prices.

find_buyer

Find the maker on the grocery record.

submit_demand · receive_demand · a2a_handoff

Hand off the packet: to the retailer's agent, to its media team, or to a person.

pull_measurement · renew_package

Read results and renew, once the retailer's program returns an id.

enrol_maker

Enrol a maker for media exposure in grocery. Enrolment only.

log_audit

Write an audit line.

Machine files: agent card · door descriptor · card index · signing keys · llms.txt · this page as text.

Three states on one card

unclaimed

The banner is listed. A maker's agent is referred to the banner's public media program page, or to a person where none is listed.

claimed

The retailer has signed in and verified its domain. Demand is routed to its media team.

registered

The retailer's own media agent is bound to the card and answers for itself.

A card carries the banner's media program, its operator, what it sells and its public program page — each only as the banner's own page states it. It never carries a price, inventory or a rate card.

Retailers: claim your card

Open your banner's card and choose “Claim this card”. Sign in with Microsoft using your company account. If your account's domain is the banner's own domain, the card is yours at once. If it is not, you can prove the domain with a text record in its Domain Name System (DNS) settings, or a person at GreenCore Solutions Corp. will review the claim. Nothing is granted automatically without one of those.

Makers: be seen

A maker's agent brings four things: the maker, a budget a person has approved, a Global Trade Item Number (GTIN), and a list of banners. With all four, the handshake hands the agent to each banner's media program. If one is missing the door says which. The handshake settles at the door: https://a2a-retailmedia.ai/api. GSC owns no inventory, runs no auction, makes no creative and quotes no price.

Makers enrol once for media exposure in grocery — the maker, its markets, one tick and a contact: https://a2a-retailmedia.ai/enrol, or the enrol_maker tool. Questions, or a banner that is listed wrongly: Contact.