feat: add compact prompt mode for local LLMs

roomote · roomote · commit 576864bdff9c · 2025-08-30T06:49:43.000Z
- Add compactPromptMode boolean setting to ProviderSettings type - Implement compact prompt generation in SYSTEM_PROMPT function - Add UI toggle in LM Studio and Ollama provider settings - Create reusable CompactPromptControl component - Add translation strings for the new feature - Include comprehensive tests for compact prompt functionality This feature addresses issue #7550 by providing a minimal prompt option that reduces context size and improves response times for local LLMs that have slower token generation speeds.
diff --git a/packages/types/src/provider-settings.ts b/packages/types/src/provider-settings.ts
@@ -103,6 +103,7 @@ const baseProviderSettingsSchema = z.object({
 	modelTemperature: z.number().nullish(),
 	rateLimitSeconds: z.number().optional(),
 	consecutiveMistakeLimit: z.number().min(0).optional(),
+	compactPromptMode: z.boolean().optional(),
 
 	// Model reasoning.
 	enableReasoningEffort: z.boolean().optional(),
diff --git a/src/core/prompts/__tests__/system-prompt.spec.ts b/src/core/prompts/__tests__/system-prompt.spec.ts
@@ -672,6 +672,194 @@ describe("SYSTEM_PROMPT", () => {
 		expect(prompt).toContain("## update_todo_list")
 	})
 
+	describe("Compact Prompt Mode", () => {
+		it("should generate a compact prompt when compactPromptMode is true", async () => {
+			const prompt = await SYSTEM_PROMPT(
+				mockContext,
+				"/test/path",
+				false, // supportsComputerUse
+				undefined, // mcpHub
+				undefined, // diffStrategy
+				undefined, // browserViewportSize
+				defaultModeSlug, // mode
+				undefined, // customModePrompts
+				undefined, // customModes
+				undefined, // globalCustomInstructions
+				undefined, // diffEnabled
+				experiments,
+				true, // enableMcpServerCreation
+				undefined, // language
+				undefined, // rooIgnoreInstructions
+				undefined, // partialReadsEnabled
+				undefined, // settings
+				undefined, // todoList
+				undefined, // modelId
+				true, // compactPromptMode
+			)
+
+			// Compact prompt should be significantly shorter
+			const normalPrompt = await SYSTEM_PROMPT(
+				mockContext,
+				"/test/path",
+				false, // supportsComputerUse
+				undefined, // mcpHub
+				undefined, // diffStrategy
+				undefined, // browserViewportSize
+				defaultModeSlug, // mode
+				undefined, // customModePrompts
+				undefined, // customModes
+				undefined, // globalCustomInstructions
+				undefined, // diffEnabled
+				experiments,
+				true, // enableMcpServerCreation
+				undefined, // language
+				undefined, // rooIgnoreInstructions
+				undefined, // partialReadsEnabled
+				undefined, // settings
+				undefined, // todoList
+				undefined, // modelId
+				false, // compactPromptMode
+			)
+
+			// Compact prompt should be shorter
+			expect(prompt.length).toBeLessThan(normalPrompt.length)
+
+			// Should still contain essential sections
+			expect(prompt).toContain("You are Roo")
+			expect(prompt).toContain("## read_file")
+			expect(prompt).toContain("## write_to_file")
+			expect(prompt).toContain("## list_files")
+			expect(prompt).toContain("## search_files")
+
+			// Should NOT contain non-essential sections
+			expect(prompt).not.toContain("MCP")
+			expect(prompt).not.toContain("browser")
+			expect(prompt).not.toContain("CAPABILITIES")
+			expect(prompt).not.toContain("MODES")
+			expect(prompt).not.toContain("execute_command") // Execute command is not included in compact mode for architect mode
+		})
+
+		it("should generate a normal prompt when compactPromptMode is false", async () => {
+			const prompt = await SYSTEM_PROMPT(
+				mockContext,
+				"/test/path",
+				false, // supportsComputerUse
+				undefined, // mcpHub
+				undefined, // diffStrategy
+				undefined, // browserViewportSize
+				defaultModeSlug, // mode
+				undefined, // customModePrompts
+				undefined, // customModes
+				undefined, // globalCustomInstructions
+				undefined, // diffEnabled
+				experiments,
+				true, // enableMcpServerCreation
+				undefined, // language
+				undefined, // rooIgnoreInstructions
+				undefined, // partialReadsEnabled
+				undefined, // settings
+				undefined, // todoList
+				undefined, // modelId
+				false, // compactPromptMode
+			)
+
+			// Normal prompt should contain all sections
+			expect(prompt).toContain("CAPABILITIES")
+			expect(prompt).toContain("MODES")
+			expect(prompt).toContain("RULES")
+			expect(prompt).toContain("SYSTEM INFORMATION")
+			expect(prompt).toContain("OBJECTIVE")
+		})
+
+		it("should generate a normal prompt when compactPromptMode is undefined", async () => {
+			const prompt = await SYSTEM_PROMPT(
+				mockContext,
+				"/test/path",
+				false, // supportsComputerUse
+				undefined, // mcpHub
+				undefined, // diffStrategy
+				undefined, // browserViewportSize
+				defaultModeSlug, // mode
+				undefined, // customModePrompts
+				undefined, // customModes
+				undefined, // globalCustomInstructions
+				undefined, // diffEnabled
+				experiments,
+				true, // enableMcpServerCreation
+				undefined, // language
+				undefined, // rooIgnoreInstructions
+				undefined, // partialReadsEnabled
+				undefined, // settings
+				undefined, // todoList
+				undefined, // modelId
+				undefined, // compactPromptMode
+			)
+
+			// Should generate normal prompt by default
+			expect(prompt).toContain("CAPABILITIES")
+			expect(prompt).toContain("MODES")
+			expect(prompt).toContain("RULES")
+			expect(prompt).toContain("SYSTEM INFORMATION")
+			expect(prompt).toContain("OBJECTIVE")
+		})
+
+		it("should not include diff tool in compact mode even when diffEnabled is true", async () => {
+			const prompt = await SYSTEM_PROMPT(
+				mockContext,
+				"/test/path",
+				false, // supportsComputerUse
+				undefined, // mcpHub
+				new MultiSearchReplaceDiffStrategy(), // diffStrategy
+				undefined, // browserViewportSize
+				defaultModeSlug, // mode
+				undefined, // customModePrompts
+				undefined, // customModes
+				undefined, // globalCustomInstructions
+				true, // diffEnabled
+				experiments,
+				true, // enableMcpServerCreation
+				undefined, // language
+				undefined, // rooIgnoreInstructions
+				undefined, // partialReadsEnabled
+				undefined, // settings
+				undefined, // todoList
+				undefined, // modelId
+				true, // compactPromptMode
+			)
+
+			// Compact mode doesn't include diff tool to keep prompt minimal
+			expect(prompt).not.toContain("apply_diff")
+		})
+
+		it("should maintain custom instructions in compact mode", async () => {
+			const prompt = await SYSTEM_PROMPT(
+				mockContext,
+				"/test/path",
+				false, // supportsComputerUse
+				undefined, // mcpHub
+				undefined, // diffStrategy
+				undefined, // browserViewportSize
+				defaultModeSlug, // mode
+				undefined, // customModePrompts
+				undefined, // customModes
+				"Test global instructions", // globalCustomInstructions
+				undefined, // diffEnabled
+				experiments,
+				true, // enableMcpServerCreation
+				undefined, // language
+				undefined, // rooIgnoreInstructions
+				undefined, // partialReadsEnabled
+				undefined, // settings
+				undefined, // todoList
+				undefined, // modelId
+				true, // compactPromptMode
+			)
+
+			// Should still include custom instructions
+			expect(prompt).toContain("Test global instructions")
+		})
+	})
+
 	afterAll(() => {
 		vi.restoreAllMocks()
 	})
diff --git a/src/core/prompts/system.ts b/src/core/prompts/system.ts
@@ -153,6 +153,7 @@ export const SYSTEM_PROMPT = async (
 	settings?: SystemPromptSettings,
 	todoList?: TodoItem[],
 	modelId?: string,
+	compactPromptMode?: boolean,
 ): Promise<string> => {
 	if (!context) {
 		throw new Error("Extension context is required for generating system prompt")
@@ -202,6 +203,62 @@ ${fileCustomSystemPrompt}
 ${customInstructions}`
 	}
 
+	// If compact prompt mode is enabled, generate a minimal prompt
+	if (compactPromptMode) {
+		const { roleDefinition, baseInstructions } = getModeSelection(mode, promptComponent, customModes)
+		const codeIndexManager = CodeIndexManager.getInstance(context, cwd)
+
+		// Generate a compact prompt with only essential sections
+		const compactPrompt = `${roleDefinition}
+
+====
+
+TOOL USE
+
+You have access to tools that are executed upon user approval. Use one tool per message.
+
+# Tools
+
+${getToolDescriptionsForMode(
+	mode,
+	cwd,
+	false, // Disable computer use for compact mode
+	codeIndexManager,
+	undefined, // No diff strategy in compact mode
+	undefined, // No browser viewport
+	undefined, // No MCP in compact mode
+	customModes,
+	experiments,
+	partialReadsEnabled,
+	settings,
+	false, // No MCP server creation
+	modelId,
+)}
+
+====
+
+RULES
+
+- Project directory: ${cwd.toPosix()}
+- Use tools efficiently to accomplish tasks
+- Wait for user response after each tool use
+- Be concise and direct in responses
+
+====
+
+OBJECTIVE
+
+Complete the user's task efficiently using available tools.
+
+${await addCustomInstructions(baseInstructions, globalCustomInstructions || "", cwd, mode, {
+	language: language ?? formatLanguage(vscode.env.language),
+	rooIgnoreInstructions,
+	settings,
+})}`
+
+		return compactPrompt
+	}
+
 	// If diff is disabled, don't pass the diffStrategy
 	const effectiveDiffStrategy = diffEnabled ? diffStrategy : undefined
 
diff --git a/src/core/task/Task.ts b/src/core/task/Task.ts
@@ -2242,6 +2242,11 @@ export class Task extends EventEmitter<TaskEvents> implements TaskLike {
 			apiConfiguration,
 		} = state ?? {}
 
+		// Check if we should use compact prompt mode for local LLM providers
+		const isLocalLLMProvider =
+			this.apiConfiguration.apiProvider === "lmstudio" || this.apiConfiguration.apiProvider === "ollama"
+		const shouldUseCompactPrompt = isLocalLLMProvider && this.apiConfiguration.compactPromptMode
+
 		return await (async () => {
 			const provider = this.providerRef.deref()
 
@@ -2276,6 +2281,7 @@ export class Task extends EventEmitter<TaskEvents> implements TaskLike {
 				},
 				undefined, // todoList
 				this.api.getModel().id,
+				shouldUseCompactPrompt,
 			)
 		})()
 	}
diff --git a/webview-ui/src/components/settings/CompactPromptControl.tsx b/webview-ui/src/components/settings/CompactPromptControl.tsx
@@ -0,0 +1,44 @@
+import React from "react"
+import { useAppTranslation } from "@src/i18n/TranslationContext"
+
+interface CompactPromptControlProps {
+	compactPromptMode?: boolean
+	onChange: (value: boolean) => void
+	providerName?: string
+}
+
+export const CompactPromptControl: React.FC<CompactPromptControlProps> = ({
+	compactPromptMode = false,
+	onChange,
+	providerName,
+}) => {
+	const { t } = useAppTranslation()
+
+	// Determine the correct translation key prefix based on provider
+	const translationPrefix = providerName === "LM Studio" ? "providers.lmStudio" : "providers.ollama"
+
+	return (
+		<div className="flex flex-col gap-2">
+			<div className="flex items-center justify-between">
+				<label htmlFor="compact-prompt-mode" className="font-medium">
+					{t(`settings:${translationPrefix}.compactPrompt.title`)}
+				</label>
+				<input
+					id="compact-prompt-mode"
+					type="checkbox"
+					checked={compactPromptMode}
+					onChange={(e) => onChange(e.target.checked)}
+					className="cursor-pointer"
+				/>
+			</div>
+			<p className="text-sm text-vscode-descriptionForeground">
+				{t(`settings:${translationPrefix}.compactPrompt.description`)}
+			</p>
+			{providerName && (
+				<p className="text-xs text-vscode-descriptionForeground italic">
+					{t(`settings:${translationPrefix}.compactPrompt.providerNote`, { provider: providerName })}
+				</p>
+			)}
+		</div>
+	)
+}
diff --git a/webview-ui/src/components/settings/providers/LMStudio.tsx b/webview-ui/src/components/settings/providers/LMStudio.tsx
@@ -13,6 +13,7 @@ import { vscode } from "@src/utils/vscode"
 
 import { inputEventTransform } from "../transforms"
 import { ModelRecord } from "@roo/api"
+import { CompactPromptControl } from "../CompactPromptControl"
 
 type LMStudioProps = {
 	apiConfiguration: ProviderSettings
@@ -207,6 +208,11 @@ export const LMStudio = ({ apiConfiguration, setApiConfigurationField }: LMStudi
 					)}
 				</>
 			)}
+			<CompactPromptControl
+				compactPromptMode={apiConfiguration?.compactPromptMode}
+				onChange={(value) => setApiConfigurationField("compactPromptMode", value)}
+				providerName="LM Studio"
+			/>
 			<div className="text-sm text-vscode-descriptionForeground">
 				<Trans
 					i18nKey="settings:providers.lmStudio.description"
diff --git a/webview-ui/src/components/settings/providers/Ollama.tsx b/webview-ui/src/components/settings/providers/Ollama.tsx
@@ -11,6 +11,7 @@ import { useRouterModels } from "@src/components/ui/hooks/useRouterModels"
 import { vscode } from "@src/utils/vscode"
 
 import { inputEventTransform } from "../transforms"
+import { CompactPromptControl } from "../CompactPromptControl"
 
 type OllamaProps = {
 	apiConfiguration: ProviderSettings
@@ -118,6 +119,11 @@ export const Ollama = ({ apiConfiguration, setApiConfigurationField }: OllamaPro
 					))}
 				</VSCodeRadioGroup>
 			)}
+			<CompactPromptControl
+				compactPromptMode={apiConfiguration?.compactPromptMode}
+				onChange={(value) => setApiConfigurationField("compactPromptMode", value)}
+				providerName="Ollama"
+			/>
 			<div className="text-sm text-vscode-descriptionForeground">
 				{t("settings:providers.ollama.description")}
 				<span className="text-vscode-errorForeground ml-1">{t("settings:providers.ollama.warning")}</span>
diff --git a/webview-ui/src/i18n/locales/en/settings.json b/webview-ui/src/i18n/locales/en/settings.json
