Puts a form live on Formhaus Cloud: without form_id it creates a new form, with form_id it publishes a new version of that form. With form_id the new version replaces the live version of that form. save_form_draft, when listed, prepares changes to a live form without going live. Returns form_id, version, endpoint (POST URL for submissions), hosted_url, embed_snippet, iframe_snippet, react_snippet, vue_snippet, dashboard_url and warnings. Without an account key it also returns claim_url, expires_at and terms_url (publishing accepts these Terms for the user), and on the first call without any key agent_key and agent_key_notice. Use it when the user needs a working form (contact, waitlist, signup, survey, feedback) without writing a backend. A new version keeps form_id, endpoint and links. allow_another_response: true shows a "Submit another response" button on the success screen of the hosted page and embed; a new form starts with false, and a new version keeps the current value unless you send it. folder (account keys only): a folder id or name from list_forms; a new form goes into it and a new version moves the form into it.

Minimal valid definition: {"id":"waitlist","title":"Join the waitlist","submit":{"label":"Join"},"fields":[{"key":"email","type":"email","label":"Email","validation":{"required":true}}]}

Rules:

• Top level needs id, title and submit {"label": "..."}.

• Each field needs key, type and label; a hidden field may omit label. Use "fields" for one step, or "steps" (each with id, title and fields) for several, never both.

• Types: text, email, phone, number, textarea, select, multiselect, radio, checkbox, switch, date, datetime, scale, rating, file. A form has at most 5 file fields; each file is up to 10 MB and must be PDF, PNG, JPEG, WebP, GIF, TXT, CSV, DOCX or XLSX. password, autocomplete, optionsFrom and custom types are refused.

• select, multiselect and radio need "options": [{"value": "a", "label": "A"}].

• scale shows numbered points from validation.min (0 or 1, default 1) to validation.max (default 5); rating shows 1 to validation.max stars (default 5). Both take 2 to 11 points and store a whole number. Up to 3 "options" whose value is a point, such as {"value": "10", "label": "Extremely likely"}, label that point. NPS is a scale from 0 to 10. Set "formatVersion": "1.3" when a form uses scale or rating.

• radio and multiselect options may have "image": an https: or data:image/ URL shown with the label. Other URLs do not show. "columns" (1 to 4) sets the picture cards per row.

• A section with "layout": "matrix" (the only layout value) shows its radio and multiselect fields as rows with shared columns; give every row the same options. A step or section may have no fields, as a welcome or statement screen.

• "validation": {"required": true, "minLength": 2, "maxLength": 200, "min": 0, "max": 10, "pattern": "^[a-z]+$"}.

• Format 1.5 ("formatVersion": "1.5") adds three features. {{key}} in a step or section title or description, or in a field label, helperText, placeholder or group itemLabel, shows the answer of an earlier field, such as "label": "Why did {{name}} join?". A multiselect option with "exclusive": true, such as "None of these", is the only answer when picked; put it last. "autocomplete" takes an HTML autofill token such as "given-name", "email" or "off". Hosted forms refuse cc-* and current-password tokens.

• At most 32 KB and 100 fields.

• JSON Schema: https://formhaus.dev/schema/form-definition.json

Store agent_key in .env as FORMHAUS_API_KEY, never in browser code; the MCP client must send it as Authorization: Bearer <agent_key>. Give claim_url to the user: they must open it within 7 days to keep the form. The text of the result has hosted_url, endpoint, embed_snippet and, when issued, agent_key and claim_url; every field is in structuredContent. On error, fix every listed path and call again.