What is MCP? Model Context Protocol explained for e-commerce and marketplace sellers
Written byLeon · Founder, CEO
What is MCP? MCP stands for Model Context Protocol: an open standard that lets an AI assistant read from and act in your systems through one connection, instead of a custom integration for every app you use. Anthropic released it on 25 November 2024 and it now sits under the Linux Foundation. For marketplace sellers the practical question is which MCP servers exist for their channels, and today the answer is almost entirely third-party; the official e-tailize MCP is in private beta with a waiting list.
What is MCP in plain English? One plug instead of one integration per tool
Before MCP, connecting an AI app to a system meant a custom integration for that exact pair: ten AI apps and ten systems meant a hundred connectors. MCP replaces that with one protocol both sides speak, so a system is exposed once as an MCP server and any AI app that speaks MCP can use it.
It is modelled on the Language Server Protocol, which solved the same problem for code editors. Think of USB-C: one port for many devices, where the cable does not care which laptop is on the other end.
Who built MCP and who governs it now
Anthropic introduced and open-sourced MCP on 25 November 2024, describing it as an open standard for building secure, two-way connections between data sources and AI-powered tools, with Block and Apollo as early adopters.
On 9 December 2025 Anthropic donated MCP to the Agentic AI Foundation, a directed fund under the Linux Foundation, co-founded by Anthropic, Block and OpenAI with support from Google, Microsoft, AWS, Cloudflare and Bloomberg.
Technical control did not move with the paperwork: the people making decisions about the protocol are still the maintainers. MCP is not a single vendor's private hook into your data, so a server built for one MCP host is designed to work with the others.
How MCP works: host, client, server
The mechanics are small: three parts, a host, a client and a server, exchanging JSON-RPC 2.0 messages.
The ten words you will meet
- MCP: the Model Context Protocol, one standard for connecting AI applications to outside data and actions.
- Host: the AI application you use, such as Claude Desktop, ChatGPT or VS Code.
- Client: the connector inside the host.
- Server: the service being connected, exposing tools, resources and prompts.
- Tool: an action the model can execute, for example get orders or update stock.
- Resource: data the assistant can read as context.
- Prompt: a templated workflow the server offers.
- Elicitation: the server asking you for input mid-task, never for passwords or keys in form mode.
- Streamable HTTP: the transport for remote servers, one endpoint with an optional streamed reply.
- OAuth 2.1: the authorisation standard when a remote server authenticates, so you grant access instead of handing over keys.
There are two ways a server connects, and it decides where your keys live. Local servers run as a subprocess on your machine over stdio and take credentials from your environment, which is why community servers ask you to paste your marketplace keys into a .env file. Remote servers use Streamable HTTP, one endpoint your client posts to; the older HTTP and SSE transport is deprecated.
Authorisation is optional in MCP. When a remote server does authenticate, the standard is OAuth 2.1: the server acts as an OAuth 2.1 resource server and publishes protected resource metadata. A server may also stop to ask you something mid-task, and passwords, API keys, tokens and payment credentials must never go through that form: they belong in URL mode, at a real web address. The current version, 2026-07-28, made MCP stateless, so any request can land on any instance behind a plain load balancer, and deprecated sampling, roots and logging, with removal no earlier than 28 July 2027.
Which AI apps support MCP today
Support is broad, and none of the vendors below has stepped back from it. The dates show how quickly this settled.
- Claude: local servers in Claude Desktop from 25 November 2024, remote connectors on claude.ai from 1 May 2025 and Claude Code from 18 June 2025, with over 950 servers in the connectors directory in July 2026.
- ChatGPT: remote MCP in the Responses API since 20 May 2025, plus a developer mode on Business, Enterprise and Edu plans that acts as a full MCP client, where write actions need confirmation.
- Microsoft: Copilot Studio reached general availability with MCP tools and resources on 29 May 2025, Microsoft 365 Copilot declarative agents on 15 December 2025.
- Developer tools: MCP support in VS Code agent mode reached general availability in July 2025, and MCP support was already in Cursor's 0.46 release of February 2025.
- Google: native MCP definitions in the Gemini API from 20 May 2025, the Gemini CLI from 25 June 2025.
- AWS: Bedrock AgentCore Gateway exposed a uniform MCP interface on 16 July 2025, and the AWS MCP Server reached general availability on 6 May 2026.
MCP marketplace or MCP server for a marketplace? Two different things
Half the confusion around MCP comes from the word marketplace, because sellers meet it in two unrelated meanings.
The first is a directory of MCP servers. Glama listed 76,043 servers on 21 August 2026, PulseMCP lists 22,029, and MCP Market keeps an e-commerce category. The official registry calls these downstream aggregators, or MCP server marketplaces.
The second is a server that exposes an e-commerce marketplace's API as tools an agent can call. A marketplace of MCP servers is a shop window; an MCP server for a marketplace is a set of keys to your seller account, and only the second one can change your listings or spend your money. Our overview of e-commerce MCP servers and our review of the bol options go through what exists per platform.
The practical consequence is which question you ask first. Picking a server out of a directory is a shopping decision you can undo by uninstalling it. Connecting a server to a sales channel is a credentials decision, because the tools it exposes run against the seller account that holds your orders, your prices and your stock, and that account keeps working for whoever holds the keys.
Above both sits the official MCP Registry, in preview since 8 September 2025 and still in preview in August 2026. It holds metadata only, and its ownership check is namespace verification: a reverse-DNS name such as com.example proves control of that domain, while io.github.username proves only a GitHub account.
What MCP changes for a marketplace seller
The concrete change is that, in principle, once a server for your channels is connected, an assistant can reach across them in one conversation, from stock and orders to listing status and performance, and prepare an action instead of you opening four seller portals. It reads and drafts, you still decide.
Just as useful is what MCP is not. It is not a feed, not a PIM and not a marketplace account, and it cannot show data a marketplace does not expose through its API. Every tool is a call into an integration that someone has to keep working when the channel changes its API, which is the unglamorous half of marketplace integration software.
Admission is a separate problem. Many European channels are gated or invite-only, and admission is not something an MCP tool does for you: the marketplace checks the legal entity, contact person and ID behind the account. Selling on bol starts with an approved seller account and a working connection.
Where this goes next: agentic commerce
Two commerce stacks are being built above this layer: the Agentic Commerce Protocol from OpenAI and Stripe, launched in September 2025, and the Universal Commerce Protocol from Google and Shopify, announced in January 2026, which runs over REST, MCP, AP2 and A2A. Payment authorisation has a standard of its own, Google's Agent Payments Protocol, donated to the FIDO Alliance in April 2026. None of it needs a decision from you this quarter: the commerce protocols read the same product, stock and price data you already maintain, so the work that pays off is keeping that data correct and reachable.
Official versus third-party, and what e-tailize does here
Official means the company behind the API publishes and maintains the server itself, and third-party means anyone else, from a community repository to a hosted wrapper that keeps your keys on its side. For marketplace channels that split is currently one-sided, and the checks it leads to, who holds your credentials, who repairs the server when a marketplace changes its API, and which tools may write, are set out with the evidence in our guide to official MCP servers for marketplaces. As of August 2026, e-tailize is the only marketplace integrator building an official MCP server, by which we mean a platform that connects one seller catalogue to several marketplaces, on the certified channel connections it holds to 200+ European marketplaces, and it is in private beta with a waiting list on the developers page.
e-tailize is a Dutch marketplace-expansion company with two halves: growth software for listings, stock, pricing, orders and analytics, and the hands-on work of getting a brand admitted to marketplaces it cannot reach alone, including gated and invite-only channels. Most tools connect you to a marketplace you were already accepted on; that admission half is the difference.
The takeaway is small. MCP decides how conveniently an assistant reaches your channel data, not whether that data exists and not whether you may sell there.
Frequently asked questions
- What does MCP stand for?
- MCP stands for Model Context Protocol. It is an open standard, introduced by Anthropic on 25 November 2024, that lets an AI application connect to outside data and actions through one protocol instead of a custom integration per app. It is now governed under the Agentic AI Foundation, a directed fund of the Linux Foundation.
- Do I need to be a developer to use MCP?
- No. In Claude you add a connector and sign in; in ChatGPT business plans and Microsoft Copilot an admin or builder connects the server for you, and the assistant can then use the tools it exposes. You need a developer only when no server exists for your system.
- Which AI apps support MCP?
- Claude on desktop, web and in Claude Code, ChatGPT through the Responses API and developer mode, Microsoft Copilot Studio and Microsoft 365 Copilot, VS Code since July 2025, Cursor, the Gemini CLI since June 2025, and AWS services. Anthropic reported over 950 servers in Claude's connectors directory in July 2026.
- Is MCP the same as an API?
- No, MCP sits on top of APIs. An API is how two systems exchange data. MCP is a standard way to describe those calls as tools, resources and prompts, so a language model can choose and use them, with a consistent way to authenticate. Behind almost every MCP server there is still an ordinary API.
- What is an MCP marketplace?
- Usually a directory of MCP servers, such as Glama, which listed 76,043 servers on 21 August 2026, PulseMCP with 22,029, or MCP Market. That is different from an MCP server for a marketplace, which exposes your seller account on a sales channel. Being listed in a directory says nothing about who maintains a server.
- What makes an MCP server official?
- Official means the company that owns the underlying platform publishes and maintains the server itself, instead of a third party wrapping its API. A community repository or a hosted wrapper can be useful, but it holds your credentials and depends on its own maintainer when the platform's API changes.