Independent groceries, agent prepared

Your agent makes the grocery list.You approve the groceries.

PIG helps your agent find groceries from Harvie's independent food network and prepare an order for you to review. You choose what to buy. You complete payment.

Connect your agent Agent instructions

PIG is in early access. Setup uses a custom connector today; PIG is not claiming a published directory listing or fully autonomous shopping.

Using ChatGPT? Start here.

No endpoint hunt.

PIG is not in the ChatGPT app directory yet. Use this exact address when ChatGPT asks for the MCP server URL.

MCP server URL

https://www.pigoffers.com/mcp

ChatGPT web setup

1Open Settings → Apps → Advanced Settings and turn on Developer mode.
2Choose Create app. Name it PIG by Harvie.
3Paste https://www.pigoffers.com/mcp into MCP server URL. Choose OAuth authentication.
4Choose Scan Tools, finish PIG sign-in, then Create. Select PIG by Harvie from the tools menu when you ask it to shop.

ChatGPT Pro

Search and read

On ChatGPT web, Developer Mode can connect PIG for live catalog search and product details. Pro cannot use PIG's cart or checkout write tools.

Business · Enterprise · Edu

Full MCP tools

Write tools can be available, subject to admin controls and ChatGPT confirmations. PIG still stops for your exact cart approval and your own Stripe payment.

No ChatGPT write tools?

Shop on PIG

Use PIG's hosted store to build the cart, review everything, and complete Stripe payment yourself.

Open PIG Supply ↗

Custom MCP apps work in ChatGPT on the web, not mobile. Agent mode does not use custom apps.

After connecting, copy this into ChatGPT

Use the connected PIG by Harvie app at https://www.pigoffers.com/mcp. First tell me whether this ChatGPT plan can only search and read or can also use write tools. Help me find groceries for my needs and budget. If write tools are available, show me the exact cart and total and wait for my approval before preparing checkout. I will complete payment myself. If write tools are unavailable, search what you can and send me to https://www.pigoffers.com/supply to finish shopping. Do not ask me to locate or provide the MCP endpoint.

For humans

Connect it. Ask it. Check it.

Choose your agent host for exact custom-connector instructions. You will sign in to PIG, review the requested household access and scopes, and explicitly approve the connection.

1
Connect
Add PIG’s public MCP URL or use the OpenAPI flow. A web address alone does not connect anything.
2
Approve
Review the agent, household, permissions, and expiry. Connecting creates no cart or order.
3
Pay yourself
The agent prepares checkout. You alone open Stripe and complete Link, 3DS, or payment.

Choose your setup

ChatGPT ↗Claude ↗Grok ↗Another MCP client ↗OpenAPI client ↗

Try asking this

A grocery prompt with guardrails.

Change the food, budget, or preferences. Keep the review and payment rules.

Use PIG by Harvie to help me prepare a grocery order. Ask what I need and my budget, then search the current catalog and show useful choices. Before preparing checkout, show every product and quantity, the full delivery address or pickup location, the date and time window in Eastern Time, delivery fee, tax, tip, and total. Wait for my clear approval before preparing checkout. I will complete Stripe Link or 3DS myself. After payment, check the same order and tell me whether it was accepted or needs attention.

For agents

One public contract. Five tools. Human payment.

REST is normative. MCP maps to the same identity, scopes, audit, idempotency, catalog, cart, checkout, and order records. Use OAuth discovery and PKCE S256; never ask the human to paste a token, device code, checkout link, address, or payment detail into connector settings.

pig_catalog_search

Search the current PIG Operations-backed catalog.

pig_catalog_get

Read fresh details for one product.

pig_cart_preview

Price and validate a cart without reserving anything.

pig_checkout_prepare

Prepare one held checkout after the human approves the preview.

pig_order_get

Read payment, allocation, fulfillment, and delivery states separately.

Before preparing checkout

Show the human all of this and wait for clear approval:

✓ Products and quantities
✓ Full delivery address or pickup
✓ Eastern date and time window
✓ Delivery fee and tax
✓ Explicit tip choice
✓ Final total

After the human pays

Read the same order. Report payment, allocation, fulfillment, and delivery separately. Say whether it was accepted or has an exception. Never infer one state from another, create a replacement after an ambiguous effect, refund, cancel, substitute, or complete payment.

Machine-readable discovery

Human setup: https://www.pigoffers.com/agents
REST discovery: https://www.pigoffers.com/api/agent/v1
OpenAPI 3.1: https://www.pigoffers.com/api/agent/v1/openapi.json
Streamable HTTP MCP: https://www.pigoffers.com/mcp
OAuth resource metadata: https://www.pigoffers.com/.well-known/oauth-protected-resource/mcp

Fresh facts, not grocery theater.

Products, prices, availability, and eligible fulfillment can change. PIG checks the current catalog and validates the address or available pickup option during preview. If no eligible option is returned, the agent must stop instead of promising delivery.

Connection help

Review or revoke a connection from PIG. Revocation must stop the old token on its next protected call. If setup expires or is rejected, start one fresh request; never replay an authorization code.

Review or revoke connections ↗