Advanced MCP Features

# Elicit Confirmation <EpicVideo url="https://www.epicai.pro/workshops/advanced-mcp-features-flccv/elicit-confirmation~oaha2" /> 👨‍💼 When users interact with our system, they sometimes initiate actions that have significant consequences (like deleting a tag or entry). To ensure users don't accidentally lose something important, we need to pause and ask for explicit confirmation before proceeding. This is where **elicitation** comes in. Instead of making assumptions, our MCP server can make a structured elicitation request. This lets us ask the user for confirmation in a way that's both clear and robust, and ensures the server only proceeds if the user truly intends to take the action. ```js const result = await agent.server.server.elicitInput({ message: `Are you sure you want to delete sandwich "The Big Dipper" (ID: 42)?`, requestedSchema: { type: 'object', properties: { confirmed: { type: 'boolean', description: 'Whether to confirm the action', }, }, }, }) const confirmed = result.action === 'accept' && result.content?.confirmed === true if (!confirmed) { const structuredContent = { success: false, sandwich: existingSandwich } return { structuredContent, content: [ { type: 'text', text: `Deleting sandwich "The Big Dipper" (ID: 42) rejected by the user.`, }, { type: 'resource_link', uri: `bobby-sandys://sandwiches/${existingSandwich.id}`, name: existingSandwich.name, mimeType: 'application/json', }, { type: 'text', text: JSON.stringify(structuredContent), }, ], } } ``` <callout-success> If the user does not confirm, the system gracefully cancels the action and provides clear feedback (no sandwiches are harmed)! </callout-success> Note you will also want to verify that the client has elicitation capabilities, and if they do not, then just proceed. ```ts // the server.server is how the MCP SDK exposes the underlying server // instance for more advanced APIs like this one. const capabilities = agent.server.server.getClientCapabilities() if (capabilities?.elicitation) { // do the elicitation } else { // proceed without elicitation } ``` This approach ensures users are always in control of important actions, and the system responds with empathy and clarity. Test this one out by using the `delete_tag` tool. 🐨 Kody will be there in <InlineFile file="src/tools.ts" /> to help you implement this.