> ## Documentation Index > Fetch the complete documentation index at: https://docs.openhermit.com/llms.txt > Use this file to discover all available pages before exploring further. # How the Script Works > What happens every time the OpenHermit script loads on a page. The script (`script.js`) is a self-contained vanilla JavaScript file under 20KB. It runs as an IIFE (immediately invoked function expression) — it never pollutes the global scope and will never break your page. ## Execution order Every time the script loads on a page, it does the following in sequence: Before anything else, the script fires a POST to `/api/ping` with the current page URL and script version. This confirms the script is correctly installed — your dashboard installation badge updates within seconds. The script adds machine-readable metadata to the page `` so AI agents can find the manifest: ```html theme={null} ``` The script checks the user-agent string for known AI crawlers (GPTBot, ClaudeBot, PerplexityBot, Google-Extended, Operator, and others) and headless browser signals. If an agent is detected, it's recorded with each event. All `

` elements on the page are scanned. For each form, the script: * Extracts all input fields (name, type, required, placeholder) * Classifies the form type: `contact_form`, `booking`, `newsletter`, `signup`, `purchase`, `quote`, `login`, `search`, `upload`, or `support` * Generates a human-readable name from aria-labels, legends, nearby headings, or the form ID * Generates a `tool_name` (snake\_case, used in the manifest) * Injects `data-mcp-action`, `data-mcp-description`, `data-mcp-params` attributes The script detects embedded widgets that aren't standard HTML forms: | Widget | Detection method | | -------- | ----------------------------------------------------- | | Calendly | `window.Calendly` object or `.calendly-inline-widget` | | Typeform | `tf-widget` element or typeform embed script | | HubSpot | `window.hbspt` or `.hs-form` | | Intercom | `window.Intercom` | | Drift | `window.drift` | | Crisp | `window.$crisp` | The script reads Schema.org JSON-LD from the page (`@type: LocalBusiness`, `Organization`, etc.) to extract the business name, description, address, and phone number. This enriches the manifest. All detected actions (and business info) are sent to `/api/actions/sync`. OpenHermit stores new actions or updates existing ones — preserving any agent prompts you've already configured. The API returns your configured prompts back. Any configured prompts are injected as a hidden off-screen `div` with an `aria-label`. This means both DOM-reading and accessibility-tree-reading agents can find your instructions without any visual impact on the page. Event listeners are added to form submit buttons. When a form is submitted, a `completion` or `error` event is sent to `/api/events` via `navigator.sendBeacon` (fire-and-forget — never slows down the page). A `MutationObserver` watches for new content added to the DOM. If a form appears after the initial load (common in React/Vue/Angular apps), the script re-runs detection automatically. *** ## Form type detection The script classifies forms by scanning their HTML for keyword signals: | Type | Signals | | -------------- | ---------------------------------------------------- | | `contact_form` | contact, message, inquiry, reach out, get in touch | | `booking` | book, appointment, schedule, reserve, calendar, slot | | `newsletter` | newsletter, subscribe, email list, updates, notify | | `signup` | sign up, register, create account, join, membership | | `purchase` | buy, checkout, order, purchase, payment, cart | | `quote` | quote, estimate, calculate, price, cost, proposal | | `login` | login, sign in, password, username | | `search` | search, find, look for | | `upload` | upload, attach, file, CV, resume, document | | `support` | support, help, ticket, issue, problem, complaint | If no signal matches, the form is classified as `contact_form` by default. *** ## Performance impact * Script size: **\< 20KB** uncompressed * Loads `async` — never blocks page rendering * Uses `sendBeacon` for event tracking — fire-and-forget, zero latency impact * Only runs after `DOMContentLoaded` — doesn't affect Time to First Byte or FCP *** ## Security The script never reads or transmits form field values. It only reads: * Field names, types, and labels (for schema building) * Page URL and title * User agent string (for agent detection) * Schema.org structured data (if present) Sensitive user input is never captured.