Hosted MCP server for Anvil — fill & generate PDFs and run Etch e-signature packets for AI agents. Hosted by usefulapi — connect from Claude, Cursor, or any MCP client.
Team and Enterprise: an Owner adds the connector for the organization first.
Run this command, then run /mcp in Claude Code to log in:
Add to Cursor or add this to ~/.cursor/mcp.json:
{
"mcpServers": {
"anvil": {
"url": "https://anvil.usefulapi.io/mcp"
}
}
}Add to VS Code or add this to .vscode/mcp.json:
{
"servers": {
"anvil": {
"type": "http",
"url": "https://anvil.usefulapi.io/mcp"
}
}
}Other MCP clients (Windsurf, Cline, Zed and more): add the URL as a remote MCP server (Streamable HTTP). The client then opens the login page in your browser. Do not add an Authorization header: see Before you connect.
The login page asks for your Anvil API key.
Find it in Anvil → Organization Settings → API keys. Your key is used only to call the API on your behalf and to derive a private account id; it is never shown to anyone.
Add only the URL. Do not add an Authorization header or an API key to the client config. The server signs you in with OAuth: the login page asks for your Anvil API key. If the config has such a header, remove it: some clients then send that header instead of the login token, and every call fails with 401.
Turn on the Anvil connector, then ask in plain words. The AI picks the tools.
| Tool | Type | What it does |
|---|---|---|
anvil_current_user | read | Current Anvil user Get the authenticated Anvil user (from the API key) and the organizations they belong to (eid, name, slug). Good first call to discover org slugs/eids for other tools. GraphQL query: currentUser. |
anvil_get_organization | read | Get organization Fetch an Anvil organization and its PDF templates (casts) and workflows (welds). Provide either its slug or its eid (at least one is required). GraphQL query: organization. |
anvil_get_cast | read | Get cast (PDF template) Fetch a cast — an Anvil PDF template — by its eid: title, version number, and whether it is a template. Use the returned eid as the cast_eid for anvil_fill_pdf. GraphQL query: cast. |
anvil_get_etch_packet | read | Get Etch e-signature packet Fetch an Etch e-signature packet by eid: its status, details URL, document group, and every signer (eid, aliasId, name, email, status, routing order). Use this to check signature progress. GraphQL query: etchPacket. |
anvil_get_weld | read | Get weld (workflow) Fetch a weld — an Anvil workflow — by eid, including its forges (the individual form steps: eid, name, slug). GraphQL query: weld. |
anvil_get_weld_data | read | Get weld data (workflow submission) Fetch a weldData record — a single submission to a weld (workflow) — by eid: completion state, test flag, and creation time. GraphQL query: weldData. |
anvil_fill_pdf | write | Fill a PDF template Fill an Anvil PDF template (cast) with data and return the finished PDF as base64. REST: POST /fill/{castEid}.pdf. Returns { filename, byteLength, pdfBase64 }. The `data` object's keys are the template's field aliases. |
anvil_generate_pdf | write | Generate a PDF from HTML or Markdown Generate a brand-new PDF from HTML or Markdown and return it as base64. REST: POST /generate-pdf. For type=html, pass data = { html, css? }. For type=markdown, pass data = [ { label, content }, ... ]. Returns { filename, byteLength, pdfBase64 }. |
anvil_create_etch_packet | write | Create Etch e-signature packet Create an Etch e-signature packet (documents + signers). GraphQL mutation: createEtchPacket. IMPORTANT: isDraft defaults to true (a safe draft that sends nothing). Setting isDraft=false with real signers SENDS signature-request emails to those signers. Use isTest=true while developing. |
anvil_generate_etch_sign_url | write | Generate Etch signing URL Generate a one-time embedded signing URL for a specific signer in an Etch packet (for iframe/redirect signing flows). GraphQL mutation: generateEtchSignURL. Returns { url }. |
anvil_usage_status | Usage status (free-tier meter) Report the caller's current free-tier usage this month: calls used, monthly limit, remaining, and whether the cap is reached. Read-only; does not count against the meter. | |
anvil_request_feature | Request a missing feature Tell usefulapi that the user needs something the Anvil tools cannot do yet (a missing tool, field or filter). Call it only when the user asks for something none of the tools can do, and tell the user that you send the request. Do not call it for errors or for normal requests. Do not include personal data, credentials or customer records. Stored with the product name and the client type (for example Claude or Cursor), without the user's account. At most 5 requests per day. Does not count against the meter. | |
anvil_upgrade | Upgrade to Pro (unlimited) Subscribe to the Pro plan for UNLIMITED Anvil tool calls (the free tier caps monthly usage). Choose monthly ($9/month) or yearly ($90/year — 2 months free) billing. Returns a Stripe Checkout link to open in your browser; after payment your account upgrades automatically. Does not count against the meter. | |
anvil_cancel_subscription | Cancel the Pro subscription Cancel the caller's Anvil Pro subscription at the end of the paid period (no refund for the current period; unlimited calls continue until then, then the free tier applies). Requires confirm: true. Run anvil_upgrade later to undo the cancel before the period ends. Does not count against the meter. |
| Plan | Price | Limit |
|---|---|---|
| Free | $0 | 100 tool calls / month |
| Pro | $9/mo · $90/yr | Unlimited |
Pro covers this Anvil server only. Subscribe with anvil_upgrade (it returns a Stripe Checkout link). Cancel any time with anvil_cancel_subscription: Pro continues to the end of the paid period, with no refund for the current period, and running anvil_upgrade before then undoes the cancel. Or write to [email protected].
No. usefulapi is an independent service. It is not affiliated with or endorsed by Anvil. The server calls the Anvil API with your own Anvil access, so it sees only the data that your account can see.
The login page asks for your Anvil API key. See Before you connect for where to find it.
No. Add only the URL. Do not add an Authorization header or an API key to the client config. The server signs you in with OAuth: the login page asks for your Anvil API key. If the config has such a header, remove it: some clients then send that header instead of the login token, and every call fails with 401.
The login stores them encrypted in the authorization grant of your connection. The server uses them to call the Anvil API for you and to derive a private account id for usage metering. usefulapi does not show them on any page or in any reply. To stop all access, remove the connector and change or delete these credentials in Anvil.
Yes, if you approve it. 4 of the 10 Anvil tools can create or change data. The other 6 are marked read-only. Most MCP clients ask you to approve a tool call before it runs.
The Free plan gives 100 tool calls / month. Pro costs $9/mo or $90/yr, with unlimited tool calls, for this Anvil server only. Run anvil_usage_status to see how many calls you used.
Ask the AI to run anvil_upgrade: it returns a Stripe Checkout link. To cancel, run anvil_cancel_subscription. Pro continues to the end of the paid period.
Tell the AI what you wanted to do. It can send the request with anvil_request_feature. We store the text with the server name, the type of AI client and the tool you tried, not with your account, and read every request when we plan new tools. You can send up to 5 requests per day.
Any client that supports remote MCP servers (Streamable HTTP) with OAuth login: Claude (web and desktop), Claude Code, Cursor, VS Code, Windsurf and others.
This is a Model Context Protocol endpoint — meant to be connected from an AI client, not opened in a browser. An invalid_token response at the URL is the auth gate working as designed; clients authenticate automatically.