RespondThat MCP server

An MCP server that lets any AI agent draft and send customer-support email replies, read a merchant's brand knowledge base, list connected mailboxes, and check credit balance — through the RespondThat API.

RespondThat is the pay-per-use AI for online sellers: it replies to customer emails in your brand voice and answers calls 24/7, in English, Spanish, Portuguese, French and German. No subscription.

Tools

Tool	Purpose
draft_reply(thread_text, language="en")	Draft an on-brand reply (not sent)
send_reply(to, subject, text)	Send through the merchant's mailbox (charges credits)
list_mailboxes()	List connected mailboxes
list_brand_kb(language="all")	Read policies / FAQ / tone
check_balance()	Credit balance + usage

Install (via skills.sh)

The package is published as a public GitHub repo and indexed by skills.sh automatically — there is no npx skills publish command (skills.sh indexes public repos, it does not take uploads):

npx skills add ryanyang828/respondthat-mcp

This drops the skill into your skills directory. Then point your MCP client at the installed server.py (see "Configure" below). No skills.sh account is required.

Configure your API token

server.py reads two environment variables:

Variable	Required	Default	Purpose
RESPONDTHAT_API_TOKEN	yes	—	Bearer token, format rt_...
RESPONDTHAT_API_BASE	no	https://respondthat.com	API base URL (override for self-host)

1. Get a token

Log into the RespondThat app (https://respondthat.com), then either:

• open the API tokens page in the dashboard and click "Create", or
• call the API while logged in (cookie session):

curl -X POST https://respondthat.com/api/token \
  -H "Content-Type: application/json" \
  -H "Cookie: session=<your_app_cookie>" \
  -d '{"name":"my-agent"}'
# => {"token":"rt_xxxx","name":"my-agent","note":"Store this securely — it is shown only once."}

The token is shown once — copy it immediately. Revoke anytime via DELETE /api/token/{id} or the dashboard.

2. Wire it into your MCP client

Most clients (Claude Desktop, Cursor, VS Code, custom) take an mcpServers block. Put the token in env so the server process can read it — do not rely on a shell export, because the client spawns the server in its own environment and won't see your shell variables:

{
  "mcpServers": {
    "respondthat": {
      "command": "python",
      "args": ["/abs/path/to/respondthat-mcp/server.py"],
      "env": {
        "RESPONDTHAT_API_TOKEN": "rt_xxxx"
      }
    }
  }
}

If you installed via npx skills add, replace the args path with the skill's installed location (typically under ~/.skills/ or your configured skills root — run npx skills list to find it).

Verify the wiring: ask your agent to call check_balance(). A successful balance response (not an auth error) means the token is correct and reachable.

Dependencies

pip install "mcp[cli]" httpx

Notes

• draft_reply never sends — review the text before calling send_reply.
• send_reply sends a real email and charges pay-per-use credits ($0.20/email). Only call it after a human has approved the text.
• All tools require the merchant's mailbox to be connected in the app first.
• RESPONDTHAT_API_TOKEN is a secret. Keep it out of source control and never commit it.