Basecamp MCP Server

/** * Shared utilities and schemas for content manipulation operations * Used by messages, comments, and other content-based tools */ import { z } from "zod"; export const htmlRules = ` HTML rules for content: * Allowed tags: div, span, h1, br, strong, em, strike, a (with an href attribute), pre, ol, ul, li, blockquote, bc-attachment (with sgid attribute). * Try to be semantic despite the limitations of tags. Use double <br> to create paragraph spacing * To mention people: <bc-attachment sgid="{ person.attachable_sgid }"></bc-attachment> * To consume less tokens, existing <bc-attachment> tags can be rewritten by dropping any attributes/inner content and just leave the "sgid" and "caption" attributes, without loosing any information * You can highlight parts of the content in this format <span style="background-color: rgb(...);">...</span> valid colors are: * red: 255, 229, 229 * yellow: 250, 247, 133 * green: 228, 248, 226 `; /** * Shared Zod schema for content operation fields * These fields can be composed into tool-specific schemas */ export const ContentOperationFields = { content: z .string() .optional() .describe( `If provided, replaces entire HTML content. Cannot be used with content_append, content_prepend, or search_replace.`, ), content_append: z .string() .optional() .describe( "Text to append to the end of current content. Cannot be used with content.", ), content_prepend: z .string() .optional() .describe( "Text to prepend to the beginning of current content. Cannot be used with content.", ), search_replace: z .array( z.object({ find: z.string().describe("Text to search for"), replace: z .string() .describe("Text to replace ALL the occurrences with"), }), ) .optional() .describe( "Array of search-replace operations to apply to current content. Cannot be used with content.", ), }; /** * Parameters for applying content operations */ export interface ContentOperationParams { content?: string; content_append?: string; content_prepend?: string; search_replace?: Array<{ find: string; replace: string }>; } /** * Apply content operations to existing content * * @param currentContent - The current content to operate on * @param operations - The operations to apply * @returns The final content after applying all operations, or undefined if no operations * @throws Error if validation fails (mutual exclusivity, no operations provided) */ export function applyContentOperations( currentContent: string, operations: ContentOperationParams, ): string | undefined { const hasPartialOps = operations.content_append || operations.content_prepend || operations.search_replace; // Validate mutual exclusivity if (operations.content && hasPartialOps) { throw new Error( "Cannot use 'content' with partial operations (content_append, content_prepend, search_replace). Use either full replacement or partial operations, not both.", ); } // If full content replacement, return it directly if (operations.content !== undefined) { return operations.content; } // If no operations at all, return undefined (no changes) if (!hasPartialOps) { return undefined; } // Apply partial operations let finalContent = currentContent; // Apply search-replace operations first if (operations.search_replace) { for (const operation of operations.search_replace) { // Check if the search string exists in the content if (!finalContent.includes(operation.find)) { throw new Error( `Search string not found: "${operation.find}". The content does not contain this text.`, ); } finalContent = finalContent.replaceAll(operation.find, operation.replace); } } // Apply prepend if (operations.content_prepend) { finalContent = operations.content_prepend + finalContent; } // Apply append if (operations.content_append) { finalContent = finalContent + operations.content_append; } return finalContent; } /** * Validate that at least one content operation is provided * * @param operations - The operations to validate * @param additionalFields - Additional field names that count as valid operations * @throws Error if no operations are provided */ export function validateContentOperations( operations: ContentOperationParams, additionalFields: string[] = [], ): void { const hasContentOp = operations.content || operations.content_append || operations.content_prepend || operations.search_replace; const hasAdditionalFields = additionalFields.some( (field) => (operations as Record<string, unknown>)[field] !== undefined, ); if (!hasContentOp && !hasAdditionalFields) { const fieldsStr = [ "content", "partial operations", ...additionalFields, ].join(", "); throw new Error(`At least one field (${fieldsStr}) must be provided`); } }