import type { FastMCP } from 'fastmcp';
import { UserError } from 'fastmcp';
import { z } from 'zod';
import { docs_v1 } from 'googleapis';
import { getDocsClient } from '../../clients.js';
import { DocumentIdParameter, NotImplementedError } from '../../types.js';
import * as GDocsHelpers from '../../googleDocsApiHelpers.js';
export function register(server: FastMCP) {
server.addTool({
name: 'appendText',
description:
'Appends plain text to the end of a document. For formatted content, use appendMarkdown instead.',
parameters: DocumentIdParameter.extend({
text: z.string().min(1).describe('The plain text to append to the end of the document.'),
addNewlineIfNeeded: z
.boolean()
.optional()
.default(true)
.describe(
"Automatically add a newline before the appended text if the doc doesn't end with one."
),
tabId: z
.string()
.optional()
.describe(
'The ID of the specific tab to append to. If not specified, appends to the first tab (or legacy document.body for documents without tabs).'
),
}),
execute: async (args, { log }) => {
const docs = await getDocsClient();
log.info(
`Appending to Google Doc: ${args.documentId}${args.tabId ? ` (tab: ${args.tabId})` : ''}`
);
try {
// Determine if we need tabs content
const needsTabsContent = !!args.tabId;
// Get the current end index
const docInfo = await docs.documents.get({
documentId: args.documentId,
includeTabsContent: needsTabsContent,
fields: needsTabsContent ? 'tabs' : 'body(content(endIndex)),documentStyle(pageSize)',
});
let endIndex = 1;
let bodyContent: any;
// If tabId is specified, find the specific tab
if (args.tabId) {
const targetTab = GDocsHelpers.findTabById(docInfo.data, args.tabId);
if (!targetTab) {
throw new UserError(`Tab with ID "${args.tabId}" not found in document.`);
}
if (!targetTab.documentTab) {
throw new UserError(
`Tab "${args.tabId}" does not have content (may not be a document tab).`
);
}
bodyContent = targetTab.documentTab.body?.content;
} else {
bodyContent = docInfo.data.body?.content;
}
if (bodyContent) {
const lastElement = bodyContent[bodyContent.length - 1];
if (lastElement?.endIndex) {
endIndex = lastElement.endIndex - 1; // Insert *before* the final newline of the doc typically
}
}
// Simpler approach: Always assume insertion is needed unless explicitly told not to add newline
const textToInsert = (args.addNewlineIfNeeded && endIndex > 1 ? '\n' : '') + args.text;
if (!textToInsert) return 'Nothing to append.';
const location: any = { index: endIndex };
if (args.tabId) {
location.tabId = args.tabId;
}
const request: docs_v1.Schema$Request = {
insertText: { location, text: textToInsert },
};
await GDocsHelpers.executeBatchUpdate(docs, args.documentId, [request]);
log.info(
`Successfully appended to doc: ${args.documentId}${args.tabId ? ` (tab: ${args.tabId})` : ''}`
);
return `Successfully appended text to ${args.tabId ? `tab ${args.tabId} in ` : ''}document ${args.documentId}.`;
} catch (error: any) {
log.error(`Error appending to doc ${args.documentId}: ${error.message || error}`);
if (error instanceof UserError) throw error;
if (error instanceof NotImplementedError) throw error;
throw new UserError(`Failed to append to doc: ${error.message || 'Unknown error'}`);
}
},
});
}
