> ## Documentation Index > Fetch the complete documentation index at: https://docs.interchange.io/llms.txt > Use this file to discover all available pages before exploring further. # MCP App HTML > Serve built MCP App widgets for iframe hosts The MCP App HTML endpoint serves the same built single-file widgets that are exposed through MCP `resources/read`, but over authenticated REST for hosts that do not have a live MCP client. ## Endpoint ```http theme={null} GET /api/v2/mcp-apps/:view/mcp-app.html ``` Use this endpoint when an Interchange-hosted UI needs to render a `ui://agentic-api/.../mcp-app.html` widget in a sandboxed iframe. The response body is HTML text and should be passed to the iframe as `srcdoc`; hosts provide widget data over the MCP Apps bridge after the iframe initializes. ## Path parameters | Parameter | Type | Description | | --------- | ------ | ----------------------------------------------------------------------------- | | `view` | string | Built widget slug. Must contain only lowercase letters, numbers, and hyphens. | Supported views: | View | Resource URI | | --------------------- | --------------------------------------------------- | | `api-call` | `ui://agentic-api/api-call/mcp-app.html` | | `account-analysis` | `ui://agentic-api/account-analysis/mcp-app.html` | | `sponsored-buyers` | `ui://agentic-api/sponsored-buyers/mcp-app.html` | | `storefront-briefs` | `ui://agentic-api/storefront-briefs/mcp-app.html` | | `test-runs` | `ui://agentic-api/test-runs/mcp-app.html` | | `selling-terms` | `ui://agentic-api/selling-terms/mcp-app.html` | | `acceptance-policy` | `ui://agentic-api/acceptance-policy/mcp-app.html` | | `business-profile` | `ui://agentic-api/business-profile/mcp-app.html` | | `merchandising-rules` | `ui://agentic-api/merchandising-rules/mcp-app.html` | | `approvals` | `ui://agentic-api/approvals/mcp-app.html` | | `seller-dashboard` | `ui://agentic-api/seller-dashboard/mcp-app.html` | | `seller-setup` | `ui://agentic-api/seller-setup/mcp-app.html` | ## Response Successful responses return the built HTML as text: ```http theme={null} HTTP/1.1 200 OK Content-Type: text/html;profile=mcp-app Cache-Control: private, max-age=300 X-Content-Type-Options: nosniff Content-Security-Policy: sandbox; default-src 'none'; script-src 'none'; base-uri 'none'; frame-ancestors 'none' ... ``` The response is intentionally cacheable only by the authenticated caller. Hosts should still apply their own iframe sandbox and bridge-level allowlists before sending data or actions into the widget. ## Errors | Status | Code | When | | ------ | ------------------ | -------------------------------------------------------- | | `400` | `VALIDATION_ERROR` | `view` contains unsupported characters. | | `404` | `NOT_FOUND` | No built MCP App widget exists for the requested `view`. | ## Example ```bash theme={null} curl https://api.interchange.io/api/v2/mcp-apps/seller-dashboard/mcp-app.html \ -H "Authorization: Bearer scope3_your_api_key_here" \ -H "Accept: text/html" ```