Manage Your Shopify Store from Claude: WhatsApp Campaigns & Loyalty over MCP

Here is a confession most vendors would bury in a changelog: we shipped write access for AI agents to Shopify stores before we had a queue of merchants asking for it. You can now manage a Shopify store from Claude — the WhatsApp marketing and loyalty side of it — through FavCRM's MCP server: build customer segments from order data, draft broadcast campaigns, create discount codes, run the loyalty program, all from a chat window.

That sentence should make you slightly nervous. It made us nervous, which is why the interesting part of this post isn't the demo — it's the design that makes agent write access defensible before anyone depends on it. No trust in the model required.

A WhatsApp MCP server for Shopify: what it actually covers

First, scope honesty. This is not an agent that edits your theme, rewrites product descriptions, or fulfils orders. Shopify's own MCP servers (Storefront, Customer Accounts, Dev) cover shopping, account management, and app development. FavCRM's MCP server is the layer on top of the store that most merchants run by hand: WhatsApp and loyalty operations.

Concretely, Claude gets roughly 20 typed tools that can:

• Read customers, orders, segments, campaign stats, and loyalty balances from the connected store.
• Build segments from real order data — "customers who spent over $500 and haven't ordered in 60 days" becomes a saved segment, not a CSV exercise.
• Draft WhatsApp campaigns against those segments, ready for review.
• Create discount codes — with hard, server-enforced limits (more below).
• Work the loyalty program — points balances and earn rules, where loyalty events (a tier reached, points earned) can trigger WhatsApp flows.

That's the job description. Now the part that matters.

Give Claude access to your Shopify store: the setup

1. Install the app from the Shopify App Store and connect your WhatsApp Business number.
2. Generate an MCP token in the FavCRM dashboard. Every token starts read-only.
3. Add the MCP server to Claude (or Cursor, or any MCP client — the client-by-client setup guide has the exact config).
4. Opt in to writes, per token, when you're ready. Read-only is the default, not a trial mode.

From there, "show me customers who abandoned carts this week, build a segment, and draft a win-back campaign" is a single instruction.

The five design rules that make write access defensible

We sorted every way an agent could hurt a store, then built one structural guardrail per failure mode. Structural is the operative word: none of these live in a system prompt.

1. Read-only by default; writes are a per-token opt-in

The lazy design is one API key that does everything the app can do. Instead, write capability is a separate flag the merchant flips on each token. If you only want Claude as an analyst, the token physically cannot mutate anything — and "the agent could read everything but couldn't have sent that" is a sentence you want available to you later.

2. Caps live in the server, not the prompt

A prompt that says "never create discounts above 30%" is a suggestion. A server-side check is physics. Here's the actual one, from the discount tool's handler:

// create_discount — enforced in the handler, before anything touches the store
const MAX_AGENT_PERCENTAGE = 50;

if (valueType === "percentage" && magnitude > MAX_AGENT_PERCENTAGE) {
  return fail(
    "Percentage discounts are capped at 50% for agent-created codes. " +
    "Create a larger promotion in Shopify directly."
  );
}

If the model asks for a 250% discount — or a 60% one — the call fails. Agent-created codes also expire after 30 days unless an end date is given; larger or permanent promotions have to be made in Shopify directly, by a human. The general rule we apply: any number an agent controls gets a server-side ceiling.

3. Irreversible sends end at a draft — there is no send_campaign tool

Writes aren't all the same risk, so we sorted them by one question: what happens if this is wrong?

• Reversible (create a segment, tag a customer): the agent just does it.
• Costly but fixable (a capped discount code): allowed, inside the schema ceilings.
• Irreversible and customer-facing (broadcasting WhatsApp to 2,000 people): the agent gets a create-campaign tool that can only produce drafts (favcrm_create_campaign — the API forces DRAFT status). A send tool does not exist.

That last one is not a missing feature. You cannot unsend a broadcast, so the chain deliberately ends at a draft in the merchant dashboard with a send button only a human can press.

4. Typed tools, no free-text escape hatches

Every tool takes a JSON schema and returns structured data. A malformed segment condition fails loudly as a validation error instead of silently becoming an empty segment — which is how you'd otherwise end up with a campaign to nobody, or everybody. (Why typed, annotated tools beat raw tool counts is its own post: MCP tool annotations and safe agents.)

5. Every write is logged

What was called, with which arguments, by which actor — plus a lastUsedAt on each token, so an unused or over-used credential is visible at a glance. An agent doesn't notice itself misbehaving the way a human operator would, so something else has to be recording. When a merchant asks "what exactly did the agent change?", the answer should be a log line, not a shrug.

The part we'd normally not tell you

We built this surface ahead of demand, on purpose. That cuts both ways. The honest downside: we can't point you at a pile of merchant case studies for the agentic workflow yet. The honest upside: every guardrail above was designed cold, as a property of the system, rather than patched in after an incident — and you get to evaluate the design itself, which is all written down here.

If you want battle-tested WhatsApp tooling and don't care about agents, incumbents like WATI have been at it longer — though third-party cost breakdowns and merchant reports through 2025 put real WATI bills at $80–120+/mo once usage stacks up. The free WhatsApp CRM for Shopify comparison and the Zoko alternative breakdown cover those trade-offs tool by tool.

What it costs

• Free ($0): shared WhatsApp inbox, contacts, customer records — a working CRM, not a timed trial.
• Pro ($19.99/mo): broadcast campaigns, segments, automated cart recovery.
• Meta's per-message fees: passed through at cost, with an estimate shown before any send. Every WhatsApp tool pays Meta; the only vendor choice is whether to mark it up.

MCP access — including the agent surface described above — rides on the same plans. The full Shopify picture is on the Shopify page.

FAQ

How do I manage my Shopify store from Claude? Install the FavCRM app from the Shopify App Store, generate an MCP token in the dashboard, and add the MCP server to Claude. Claude then has ~20 typed tools for the store's WhatsApp and loyalty layer: segments from order data, campaign drafts, capped discount codes, loyalty balances. Tokens start read-only; writes are a per-token opt-in.

How do I give Claude access to my Shopify store without risking it? Use a scoped token rather than a master key. In FavCRM that means: read-only by default, writes flipped on per token, hard server-side caps on every number the agent controls, no tool for irreversible sends, an audit log of every write, and a lastUsedAt on every token. The guardrails are properties of the API, not instructions in a prompt.

Is there a WhatsApp MCP server for Shopify? Yes — FavCRM's MCP server is the WhatsApp + loyalty layer for Shopify stores: inbox, segments, campaign drafts, discounts, and loyalty over typed MCP tools. It's a different surface from Shopify's own MCP servers (Storefront, Customer Accounts, Dev), which handle shopping, account management, and app development rather than WhatsApp marketing.

Can the AI agent send a WhatsApp campaign by itself? No, by design. The agent can build the segment and draft the campaign, but there is no send_campaign tool — the draft lands in the merchant dashboard, and a human presses send. Broadcasts can't be unsent, so that step stays human.

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Want your store's WhatsApp and loyalty runnable from a chat window — with the guardrails above, not vibes? Install FavCRM on Shopify and start on the free tier, or see the full setup on the Shopify page.