snapshot of https://github.com/tldraw/tldraw.git (main, 2026-09-23; blobs > 131072B omitted)

templates/agent/worker/prompt/buildMessages.ts

@@ -0,0 +1,98 @@
+import { ModelMessage, UserContent } from 'ai'
+import { AgentMessage, AgentMessageContent } from '../../shared/types/AgentMessage'
+import { AgentPrompt } from '../../shared/types/AgentPrompt'
+import { getPromptPartDefinition, PromptPart } from '../../shared/types/PromptPart'
+
+export function buildMessages(prompt: AgentPrompt): ModelMessage[] {
+	const allMessages: AgentMessage[] = []
+
+	// Build messages from each prompt part using shared definitions
+	for (const part of Object.values(prompt)) {
+		const messages = buildMessagesFromPart(part)
+		allMessages.push(...messages)
+	}
+
+	// Sort by priority (higher priority = later in prompt)
+	allMessages.sort((a, b) => a.priority - b.priority)
+
+	return toModelMessages(allMessages)
+}
+
+/**
+ * Build messages from a prompt part using its definition.
+ * This is used by the worker to convert prompt parts into messages for the model.
+ */
+function buildMessagesFromPart(part: PromptPart): AgentMessage[] {
+	const definition = getPromptPartDefinition(part.type)
+
+	// If the definition has a custom buildMessages function, use it
+	if (definition.buildMessages) {
+		return definition.buildMessages(part)
+	}
+
+	// Otherwise, use the default logic with buildContent
+	return defaultBuildMessagesFromPart(part)
+}
+
+/**
+ * Default message building logic that uses buildContent.
+ */
+function defaultBuildMessagesFromPart(part: PromptPart): AgentMessage[] {
+	const definition = getPromptPartDefinition(part.type)
+
+	// Get content strings from the definition
+	const content = definition.buildContent ? definition.buildContent(part) : []
+
+	if (!content || content.length === 0) {
+		return []
+	}
+
+	// Convert content strings to message content (handling images)
+	const messageContent: AgentMessageContent[] = []
+	for (const item of content) {
+		if (typeof item === 'string' && item.startsWith('data:image/')) {
+			messageContent.push({
+				type: 'image',
+				image: item,
+			})
+		} else {
+			messageContent.push({
+				type: 'text',
+				text: item,
+			})
+		}
+	}
+
+	// Get priority from definition (default to 0)
+	const priority = definition.priority ?? 0
+
+	return [{ role: 'user', content: messageContent, priority }]
+}
+
+/**
+ * Convert AgentMessage[] to ModelMessage[] for the AI SDK
+ */
+function toModelMessages(agentMessages: AgentMessage[]): ModelMessage[] {
+	return agentMessages.map((tlMessage) => {
+		const content: UserContent = []
+
+		for (const contentItem of tlMessage.content) {
+			if (contentItem.type === 'image') {
+				content.push({
+					type: 'image',
+					image: contentItem.image!,
+				})
+			} else {
+				content.push({
+					type: 'text',
+					text: contentItem.text!,
+				})
+			}
+		}
+
+		return {
+			role: tlMessage.role,
+			content,
+		} as ModelMessage
+	})
+}