Mainstreet MCP server

Main Street MCP

A free, industry-specific MCP server that gives a small business's AI assistants (ChatGPT, Claude, etc.) reliable answers about the business itself — hours, menu/services, FAQs, staff, and how to book — instead of hallucinating them. One business.yaml file per business; no code changes required to run it.

Quickstart (business owner)

1. Install Node.js 20+ (or use the version already on your machine — check with node -v).
2. Generate a starter config for your industry:

npx -y mainstreet-mcp init --industry restaurant

Replace restaurant with your industry. Supported industries: restaurant, dental, law-firm, home-services, salon-spa, fitness-studio, real-estate-agent, auto-repair, insurance-agency, church.

This writes business.yaml in the current directory — edit it with your business's real name, hours, menu/services, FAQs, etc. (Use --out for a different name; every other command then needs --config .)

1. Check your edits are valid:

npx -y mainstreet-mcp validate

A broken file (bad YAML, a typo'd industry, a field that doesn't fit) prints a specific, readable error instead of a stack trace.

stdio servers, add an entry like:

1. Point your AI assistant at it. For a local MCP client (e.g. Claude Desktop) that spawns

{
     "mcpServers": {
       "my-business": {
         "command": "npx",
         "args": ["-y", "mainstreet-mcp", "--config", "/absolute/path/to/business.yaml"]
       }
     }
   }

To serve over HTTP instead (e.g. for a hosted deployment), run:

npx -y mainstreet-mcp serve --http --port 3000

The HTTP server only binds to 127.0.0.1 and validates the Host/Origin headers on every request — put a reverse proxy in front of it for anything beyond local testing.

What it gives an AI assistant

Every business gets 7 universal tools regardless of industry:

timezone, including overnight hours and holiday/exception overrides

• getbusinessprofile — name, description, contact info, address, policies
• checkopenstatus — open/closed right now (or at a given time), in the business's own

when nothing matches confidently

• search_offerings — free-text search over whatever the business sells/offers
• answer_question — looks up configured FAQs; returns found: false rather than a guess

by industry-specific guardrails before it's accepted

• list_staff — configured staff, roles, bios, credentials
• getbookingoptions — how to actually book (phone/online/walk-in/email)
• submit_inquiry — lets a customer leave a message; rate-limited, sanitized, and screened

On top of that, each industry preset turns on a handful of capabilities — pluggable tool modules — matched to that industry:

Every tool ships an outputSchema and returns structuredContent, so a calling agent gets typed data back, not just prose to parse.

Guardrails

Some presets screen submit_inquiry messages before accepting them, on top of the universal sanitization (HTML/control-char stripping, length caps, rate limiting):

Shortened. The full README is on GitHub.