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AI and tools, updated

MCP server

The FormThunder MCP server lets an AI agent configure your forms. It runs locally through npx formthunder mcp, or you can connect to the hosted endpoint at https://formthunder.com/api/mcp. Agents can create forms, write the code into your project, match emails to your brand and send real tests. MCP is included on every plan, Free too.

Claude Code

bash
claude mcp add formthunder -- npx -y formthunder mcp

The first run needs a key. Log in from a terminal, or set FORMTHUNDER_API_KEY.

bash
npx formthunder login

For the whole run with the prompt to use, read how to let Claude Code set up a contact form with MCP.

Cursor and other clients

Most clients take a JSON config. In Cursor, that's .cursor/mcp.json.

json
{
  "mcpServers": {
    "formthunder": {
      "command": "npx",
      "args": ["-y", "formthunder", "mcp"],
      "env": { "FORMTHUNDER_API_KEY": "ft_live_..." }
    }
  }
}

Keep that file out of git if it holds a key.

Hosted endpoint

The hosted server speaks Streamable HTTP and is stateless. Authenticate with an API key as a bearer token.

bash
claude mcp add --transport http formthunder https://formthunder.com/api/mcp \
  --header "Authorization: Bearer ft_live_..."

Tools

See the full list of tools. The usual sequence is below, and the server gives agents the same instructions.

JobTools, in order
Add a form to a sitelist_linked_emails, create_form, get_snippet, test_form, check_form_on_site
Match emails to a siteextract_brand_from_website, set_brand, list_template_variables, generate_template, preview_template, send_test_template, update_form
Work on a clientlist_clients, then account_id on any tool

Prompts

PromptWhat it does
setup_contact_formCreates a form, puts it in the site, sends a real test and checks the live page.
match_website_brandingReads a site's branding, saves the brand kit, builds a matching template, tests it and attaches it.

Errors an agent can act on

Every error has a hint that says what to do next. Many results also carry a next_step field.

json
{
  "error": {
    "code": "feature_requires_pro",
    "message": "Webhooks need the Pro plan.",
    "hint": "Upgrade at https://formthunder.com/app/billing or run `formthunder billing upgrade`.",
    "docs": "https://formthunder.com/docs/webhooks"
  }
}

Keeping a human in the loop

Tools that delete data or cost money carry annotations and descriptions that tell the agent to confirm with you first. Your MCP client can also ask before each tool call. get_audit_log shows what changed and which key changed it, so you can review a session afterwards.

Only you can click an email verification link, so an agent has to ask you to do that when it adds a new recipient.

Other machine-readable files