Register MCP tools via dynamic imports

Co-authored-by: Kent C. Dodds <me+github@kentcdodds.com>

Author: cursoragent

docs/mcp-server-patterns.md

@@ -283,7 +283,7 @@ tool module and registers them.
 
 ```typescript
 // mcp/tools/do-math.ts
-export async function registerDoMathTool(agent: MCP) {
+export async function registerTool(agent: MCP) {
 	agent.server.registerTool(
 		'do_math',
 		{
@@ -296,9 +296,10 @@ export async function registerDoMathTool(agent: MCP) {
 }
 
 // mcp/register-tools.ts
-import { registerDoMathTool } from './tools/do-math.ts'
 export async function registerTools(agent: MCP) {
-	await registerDoMathTool(agent)
+	await import('./tools/do-math.ts').then(({ registerTool }) =>
+		registerTool(agent),
+	)
 }
 ```
 

mcp/register-tools.ts

@@ -1,6 +1,7 @@
 import { type MCP } from './index.ts'
-import { registerDoMathTool } from './tools/do-math.ts'
 
 export async function registerTools(agent: MCP) {
-	await registerDoMathTool(agent)
+	await import('./tools/do-math.ts').then(({ registerTool }) =>
+		registerTool(agent),
+	)
 }

mcp/tools/do-math.ts

@@ -41,7 +41,7 @@ function formatNumberForMarkdown(value: number, precision: number) {
 	return rounded.includes('.') ? rounded.replace(/\.?0+$/, '') : rounded
 }
 
-export async function registerDoMathTool(agent: MCP) {
+export async function registerTool(agent: MCP) {
 	agent.server.registerTool(
 		doMathTool.name,
 		{