feat(coding-agent): ResourceLoader, package management, and /reload command (#645)

- Add ResourceLoader interface and DefaultResourceLoader implementation
- Add PackageManager for npm/git extension sources with install/remove/update
- Add session.reload() and session.bindExtensions() APIs
- Add /reload command in interactive mode
- Add CLI flags: --skill, --theme, --prompt-template, --no-themes, --no-prompt-templates
- Add pi install/remove/update commands for extension management
- Refactor settings.json to use arrays for skills, prompts, themes
- Remove legacy SkillsSettings source flags and filters
- Update SDK examples and documentation for ResourceLoader pattern
- Add theme registration and loadThemeFromPath for dynamic themes
- Add getShellEnv to include bin dir in PATH for bash commands

packages/coding-agent/test/agent-session-branching.test.ts

@@ -19,7 +19,7 @@ import { ModelRegistry } from "../src/core/model-registry.js";
 import { SessionManager } from "../src/core/session-manager.js";
 import { SettingsManager } from "../src/core/settings-manager.js";
 import { codingTools } from "../src/core/tools/index.js";
-import { API_KEY } from "./utilities.js";
+import { API_KEY, createTestResourceLoader } from "./utilities.js";
 
 describe.skipIf(!API_KEY)("AgentSession forking", () => {
 	let session: AgentSession;
@@ -61,7 +61,9 @@ describe.skipIf(!API_KEY)("AgentSession forking", () => {
 			agent,
 			sessionManager,
 			settingsManager,
+			cwd: tempDir,
 			modelRegistry,
+			resourceLoader: createTestResourceLoader(),
 		});
 
 		// Must subscribe to enable session persistence

packages/coding-agent/test/agent-session-compaction.test.ts

@@ -19,7 +19,7 @@ import { ModelRegistry } from "../src/core/model-registry.js";
 import { SessionManager } from "../src/core/session-manager.js";
 import { SettingsManager } from "../src/core/settings-manager.js";
 import { codingTools } from "../src/core/tools/index.js";
-import { API_KEY } from "./utilities.js";
+import { API_KEY, createTestResourceLoader } from "./utilities.js";
 
 describe.skipIf(!API_KEY)("AgentSession compaction e2e", () => {
 	let session: AgentSession;
@@ -67,7 +67,9 @@ describe.skipIf(!API_KEY)("AgentSession compaction e2e", () => {
 			agent,
 			sessionManager,
 			settingsManager,
+			cwd: tempDir,
 			modelRegistry,
+			resourceLoader: createTestResourceLoader(),
 		});
 
 		// Subscribe to track events

packages/coding-agent/test/agent-session-concurrent.test.ts

@@ -13,6 +13,7 @@ import { AuthStorage } from "../src/core/auth-storage.js";
 import { ModelRegistry } from "../src/core/model-registry.js";
 import { SessionManager } from "../src/core/session-manager.js";
 import { SettingsManager } from "../src/core/settings-manager.js";
+import { createTestResourceLoader } from "./utilities.js";
 
 // Mock stream that mimics AssistantMessageEventStream
 class MockAssistantStream extends EventStream<AssistantMessageEvent, AssistantMessage> {
@@ -107,7 +108,9 @@ describe("AgentSession concurrent prompt guard", () => {
 			agent,
 			sessionManager,
 			settingsManager,
+			cwd: tempDir,
 			modelRegistry,
+			resourceLoader: createTestResourceLoader(),
 		});
 
 		return session;
@@ -197,7 +200,9 @@ describe("AgentSession concurrent prompt guard", () => {
 			agent,
 			sessionManager,
 			settingsManager,
+			cwd: tempDir,
 			modelRegistry,
+			resourceLoader: createTestResourceLoader(),
 		});
 
 		// First prompt completes

packages/coding-agent/test/args.test.ts

@@ -163,6 +163,42 @@ describe("parseArgs", () => {
 		});
 	});
 
+	describe("--skill flag", () => {
+		test("parses single --skill", () => {
+			const result = parseArgs(["--skill", "./skill-dir"]);
+			expect(result.skills).toEqual(["./skill-dir"]);
+		});
+
+		test("parses multiple --skill flags", () => {
+			const result = parseArgs(["--skill", "./skill-a", "--skill", "./skill-b"]);
+			expect(result.skills).toEqual(["./skill-a", "./skill-b"]);
+		});
+	});
+
+	describe("--prompt-template flag", () => {
+		test("parses single --prompt-template", () => {
+			const result = parseArgs(["--prompt-template", "./prompts"]);
+			expect(result.promptTemplates).toEqual(["./prompts"]);
+		});
+
+		test("parses multiple --prompt-template flags", () => {
+			const result = parseArgs(["--prompt-template", "./one", "--prompt-template", "./two"]);
+			expect(result.promptTemplates).toEqual(["./one", "./two"]);
+		});
+	});
+
+	describe("--theme flag", () => {
+		test("parses single --theme", () => {
+			const result = parseArgs(["--theme", "./theme.json"]);
+			expect(result.themes).toEqual(["./theme.json"]);
+		});
+
+		test("parses multiple --theme flags", () => {
+			const result = parseArgs(["--theme", "./dark.json", "--theme", "./light.json"]);
+			expect(result.themes).toEqual(["./dark.json", "./light.json"]);
+		});
+	});
+
 	describe("--no-skills flag", () => {
 		test("parses --no-skills flag", () => {
 			const result = parseArgs(["--no-skills"]);
@@ -170,6 +206,20 @@ describe("parseArgs", () => {
 		});
 	});
 
+	describe("--no-prompt-templates flag", () => {
+		test("parses --no-prompt-templates flag", () => {
+			const result = parseArgs(["--no-prompt-templates"]);
+			expect(result.noPromptTemplates).toBe(true);
+		});
+	});
+
+	describe("--no-themes flag", () => {
+		test("parses --no-themes flag", () => {
+			const result = parseArgs(["--no-themes"]);
+			expect(result.noThemes).toBe(true);
+		});
+	});
+
 	describe("--no-tools flag", () => {
 		test("parses --no-tools flag", () => {
 			const result = parseArgs(["--no-tools"]);

packages/coding-agent/test/compaction-extensions.test.ts

@@ -13,7 +13,6 @@ import { AuthStorage } from "../src/core/auth-storage.js";
 import {
 	createExtensionRuntime,
 	type Extension,
-	ExtensionRunner,
 	type SessionBeforeCompactEvent,
 	type SessionCompactEvent,
 	type SessionEvent,
@@ -22,13 +21,13 @@ import { ModelRegistry } from "../src/core/model-registry.js";
 import { SessionManager } from "../src/core/session-manager.js";
 import { SettingsManager } from "../src/core/settings-manager.js";
 import { codingTools } from "../src/core/tools/index.js";
+import { createTestResourceLoader } from "./utilities.js";
 
 const API_KEY = process.env.ANTHROPIC_OAUTH_TOKEN || process.env.ANTHROPIC_API_KEY;
 
 describe.skipIf(!API_KEY)("Compaction extensions", () => {
 	let session: AgentSession;
 	let tempDir: string;
-	let extensionRunner: ExtensionRunner;
 	let capturedEvents: SessionEvent[];
 
 	beforeEach(() => {
@@ -101,51 +100,18 @@ describe.skipIf(!API_KEY)("Compaction extensions", () => {
 		const modelRegistry = new ModelRegistry(authStorage);
 
 		const runtime = createExtensionRuntime();
-		extensionRunner = new ExtensionRunner(extensions, runtime, tempDir, sessionManager, modelRegistry);
-		extensionRunner.initialize(
-			// ExtensionActions
-			{
-				sendMessage: async () => {},
-				sendUserMessage: async () => {},
-				appendEntry: async () => {},
-				setSessionName: () => {},
-				getSessionName: () => undefined,
-				setLabel: () => {},
-				getActiveTools: () => [],
-				getAllTools: () => [],
-				setActiveTools: () => {},
-				setModel: async () => false,
-				getThinkingLevel: () => "off",
-				setThinkingLevel: () => {},
-			},
-			// ExtensionContextActions
-			{
-				getModel: () => session.model,
-				isIdle: () => !session.isStreaming,
-				abort: () => session.abort(),
-				hasPendingMessages: () => session.pendingMessageCount > 0,
-				shutdown: () => {},
-				getContextUsage: () => session.getContextUsage(),
-				compact: (options) => {
-					void (async () => {
-						try {
-							const result = await session.compact(options?.customInstructions);
-							options?.onComplete?.(result);
-						} catch (error) {
-							const err = error instanceof Error ? error : new Error(String(error));
-							options?.onError?.(err);
-						}
-					})();
-				},
-			},
-		);
+		const resourceLoader = {
+			...createTestResourceLoader(),
+			getExtensions: () => ({ extensions, errors: [], runtime }),
+		};
 
 		session = new AgentSession({
 			agent,
 			sessionManager,
 			settingsManager,
-			extensionRunner,
+			cwd: tempDir,
 			modelRegistry,
+			resourceLoader,
 		});
 
 		return session;

packages/coding-agent/test/compaction-thinking-model.test.ts

@@ -19,7 +19,13 @@ import { ModelRegistry } from "../src/core/model-registry.js";
 import { SessionManager } from "../src/core/session-manager.js";
 import { SettingsManager } from "../src/core/settings-manager.js";
 import { codingTools } from "../src/core/tools/index.js";
-import { API_KEY, getRealAuthStorage, hasAuthForProvider, resolveApiKey } from "./utilities.js";
+import {
+	API_KEY,
+	createTestResourceLoader,
+	getRealAuthStorage,
+	hasAuthForProvider,
+	resolveApiKey,
+} from "./utilities.js";
 
 // Check for auth
 const HAS_ANTIGRAVITY_AUTH = hasAuthForProvider("google-antigravity");
@@ -81,7 +87,9 @@ describe.skipIf(!HAS_ANTIGRAVITY_AUTH)("Compaction with thinking models (Antigra
 			agent,
 			sessionManager,
 			settingsManager,
+			cwd: tempDir,
 			modelRegistry,
+			resourceLoader: createTestResourceLoader(),
 		});
 
 		session.subscribe(() => {});
@@ -175,7 +183,9 @@ describe.skipIf(!HAS_ANTHROPIC_AUTH)("Compaction with thinking models (Anthropic
 			agent,
 			sessionManager,
 			settingsManager,
+			cwd: tempDir,
 			modelRegistry,
+			resourceLoader: createTestResourceLoader(),
 		});
 
 		session.subscribe(() => {});

packages/coding-agent/test/sdk-skills.test.ts

@@ -2,6 +2,8 @@ import { mkdirSync, rmSync, writeFileSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
 import { afterEach, beforeEach, describe, expect, it } from "vitest";
+import { createExtensionRuntime } from "../src/core/extensions/loader.js";
+import type { ResourceLoader } from "../src/core/resource-loader.js";
 import { createAgentSession } from "../src/core/sdk.js";
 import { SessionManager } from "../src/core/session-manager.js";
 
@@ -47,21 +49,30 @@ This is a test skill.
 		expect(session.skills.some((s) => s.name === "test-skill")).toBe(true);
 	});
 
-	it("should have empty skills when options.skills is empty array (--no-skills)", async () => {
+	it("should have empty skills when resource loader returns none (--no-skills)", async () => {
+		const resourceLoader: ResourceLoader = {
+			getExtensions: () => ({ extensions: [], errors: [], runtime: createExtensionRuntime() }),
+			getSkills: () => ({ skills: [], diagnostics: [] }),
+			getPrompts: () => ({ prompts: [], diagnostics: [] }),
+			getThemes: () => ({ themes: [], diagnostics: [] }),
+			getAgentsFiles: () => ({ agentsFiles: [] }),
+			getSystemPrompt: () => undefined,
+			getAppendSystemPrompt: () => [],
+			reload: async () => {},
+		};
+
 		const { session } = await createAgentSession({
 			cwd: tempDir,
 			agentDir: tempDir,
 			sessionManager: SessionManager.inMemory(),
-			skills: [], // Explicitly empty - like --no-skills
+			resourceLoader,
 		});
 
-		// session.skills should be empty
 		expect(session.skills).toEqual([]);
-		// No warnings since we didn't discover
 		expect(session.skillWarnings).toEqual([]);
 	});
 
-	it("should use provided skills when options.skills is explicitly set", async () => {
+	it("should use provided skills when resource loader supplies them", async () => {
 		const customSkill = {
 			name: "custom-skill",
 			description: "A custom skill",
@@ -70,16 +81,25 @@ This is a test skill.
 			source: "custom" as const,
 		};
 
+		const resourceLoader: ResourceLoader = {
+			getExtensions: () => ({ extensions: [], errors: [], runtime: createExtensionRuntime() }),
+			getSkills: () => ({ skills: [customSkill], diagnostics: [] }),
+			getPrompts: () => ({ prompts: [], diagnostics: [] }),
+			getThemes: () => ({ themes: [], diagnostics: [] }),
+			getAgentsFiles: () => ({ agentsFiles: [] }),
+			getSystemPrompt: () => undefined,
+			getAppendSystemPrompt: () => [],
+			reload: async () => {},
+		};
+
 		const { session } = await createAgentSession({
 			cwd: tempDir,
 			agentDir: tempDir,
 			sessionManager: SessionManager.inMemory(),
-			skills: [customSkill],
+			resourceLoader,
 		});
 
-		// session.skills should contain only the provided skill
 		expect(session.skills).toEqual([customSkill]);
-		// No warnings since we didn't discover
 		expect(session.skillWarnings).toEqual([]);
 	});
 });

packages/coding-agent/test/skills.test.ts

@@ -254,152 +254,44 @@ describe("skills", () => {
 	});
 
 	describe("loadSkills with options", () => {
-		it("should load from customDirectories only when built-ins disabled", () => {
-			const { skills } = loadSkills({
-				enableCodexUser: false,
-				enableClaudeUser: false,
-				enableClaudeProject: false,
-				enablePiUser: false,
-				enablePiProject: false,
-				customDirectories: [fixturesDir],
+		const emptyAgentDir = resolve(__dirname, "fixtures/empty-agent");
+		const emptyCwd = resolve(__dirname, "fixtures/empty-cwd");
+
+		it("should load from explicit skillPaths", () => {
+			const { skills, warnings } = loadSkills({
+				agentDir: emptyAgentDir,
+				cwd: emptyCwd,
+				skillPaths: [join(fixturesDir, "valid-skill")],
 			});
-			expect(skills.length).toBeGreaterThan(0);
-			expect(skills.every((s) => s.source === "custom")).toBe(true);
+			expect(skills).toHaveLength(1);
+			expect(skills[0].source).toBe("custom");
+			expect(warnings).toHaveLength(0);
 		});
 
-		it("should filter out ignoredSkills", () => {
-			const { skills } = loadSkills({
-				enableCodexUser: false,
-				enableClaudeUser: false,
-				enableClaudeProject: false,
-				enablePiUser: false,
-				enablePiProject: false,
-				customDirectories: [join(fixturesDir, "valid-skill")],
-				ignoredSkills: ["valid-skill"],
+		it("should warn when skill path does not exist", () => {
+			const { skills, warnings } = loadSkills({
+				agentDir: emptyAgentDir,
+				cwd: emptyCwd,
+				skillPaths: ["/non/existent/path"],
 			});
 			expect(skills).toHaveLength(0);
+			expect(warnings.some((w) => w.message.includes("does not exist"))).toBe(true);
 		});
 
-		it("should support glob patterns in ignoredSkills", () => {
-			const { skills } = loadSkills({
-				enableCodexUser: false,
-				enableClaudeUser: false,
-				enableClaudeProject: false,
-				enablePiUser: false,
-				enablePiProject: false,
-				customDirectories: [fixturesDir],
-				ignoredSkills: ["valid-*"],
-			});
-			expect(skills.every((s) => !s.name.startsWith("valid-"))).toBe(true);
-		});
-
-		it("should have ignoredSkills take precedence over includeSkills", () => {
-			const { skills } = loadSkills({
-				enableCodexUser: false,
-				enableClaudeUser: false,
-				enableClaudeProject: false,
-				enablePiUser: false,
-				enablePiProject: false,
-				customDirectories: [fixturesDir],
-				includeSkills: ["valid-*"],
-				ignoredSkills: ["valid-skill"],
-			});
-			// valid-skill should be excluded even though it matches includeSkills
-			expect(skills.every((s) => s.name !== "valid-skill")).toBe(true);
-		});
-
-		it("should expand ~ in customDirectories", () => {
+		it("should expand ~ in skillPaths", () => {
 			const homeSkillsDir = join(homedir(), ".pi/agent/skills");
 			const { skills: withTilde } = loadSkills({
-				enableCodexUser: false,
-				enableClaudeUser: false,
-				enableClaudeProject: false,
-				enablePiUser: false,
-				enablePiProject: false,
-				customDirectories: ["~/.pi/agent/skills"],
+				agentDir: emptyAgentDir,
+				cwd: emptyCwd,
+				skillPaths: ["~/.pi/agent/skills"],
 			});
 			const { skills: withoutTilde } = loadSkills({
-				enableCodexUser: false,
-				enableClaudeUser: false,
-				enableClaudeProject: false,
-				enablePiUser: false,
-				enablePiProject: false,
-				customDirectories: [homeSkillsDir],
+				agentDir: emptyAgentDir,
+				cwd: emptyCwd,
+				skillPaths: [homeSkillsDir],
 			});
 			expect(withTilde.length).toBe(withoutTilde.length);
 		});
-
-		it("should return empty when all sources disabled and no custom dirs", () => {
-			const { skills } = loadSkills({
-				enableCodexUser: false,
-				enableClaudeUser: false,
-				enableClaudeProject: false,
-				enablePiUser: false,
-				enablePiProject: false,
-			});
-			expect(skills).toHaveLength(0);
-		});
-
-		it("should filter skills with includeSkills glob patterns", () => {
-			// Load all skills from fixtures
-			const { skills: allSkills } = loadSkills({
-				enableCodexUser: false,
-				enableClaudeUser: false,
-				enableClaudeProject: false,
-				enablePiUser: false,
-				enablePiProject: false,
-				customDirectories: [fixturesDir],
-			});
-			expect(allSkills.length).toBeGreaterThan(0);
-
-			// Filter to only include "valid-skill"
-			const { skills: filtered } = loadSkills({
-				enableCodexUser: false,
-				enableClaudeUser: false,
-				enableClaudeProject: false,
-				enablePiUser: false,
-				enablePiProject: false,
-				customDirectories: [fixturesDir],
-				includeSkills: ["valid-skill"],
-			});
-			expect(filtered).toHaveLength(1);
-			expect(filtered[0].name).toBe("valid-skill");
-		});
-
-		it("should support glob patterns in includeSkills", () => {
-			const { skills } = loadSkills({
-				enableCodexUser: false,
-				enableClaudeUser: false,
-				enableClaudeProject: false,
-				enablePiUser: false,
-				enablePiProject: false,
-				customDirectories: [fixturesDir],
-				includeSkills: ["valid-*"],
-			});
-			expect(skills.length).toBeGreaterThan(0);
-			expect(skills.every((s) => s.name.startsWith("valid-"))).toBe(true);
-		});
-
-		it("should return all skills when includeSkills is empty", () => {
-			const { skills: withEmpty } = loadSkills({
-				enableCodexUser: false,
-				enableClaudeUser: false,
-				enableClaudeProject: false,
-				enablePiUser: false,
-				enablePiProject: false,
-				customDirectories: [fixturesDir],
-				includeSkills: [],
-			});
-			const { skills: withoutOption } = loadSkills({
-				enableCodexUser: false,
-				enableClaudeUser: false,
-				enableClaudeProject: false,
-				enablePiUser: false,
-				enablePiProject: false,
-				customDirectories: [fixturesDir],
-			});
-			expect(withEmpty.length).toBe(withoutOption.length);
-		});
 	});
 
 	describe("collision handling", () => {

packages/coding-agent/test/utilities.ts

@@ -9,7 +9,9 @@ import { Agent } from "@mariozechner/pi-agent-core";
 import { getModel, getOAuthApiKey, type OAuthCredentials, type OAuthProvider } from "@mariozechner/pi-ai";
 import { AgentSession } from "../src/core/agent-session.js";
 import { AuthStorage } from "../src/core/auth-storage.js";
+import { createExtensionRuntime } from "../src/core/extensions/loader.js";
 import { ModelRegistry } from "../src/core/model-registry.js";
+import type { ResourceLoader } from "../src/core/resource-loader.js";
 import { SessionManager } from "../src/core/session-manager.js";
 import { SettingsManager } from "../src/core/settings-manager.js";
 import { codingTools } from "../src/core/tools/index.js";
@@ -172,6 +174,19 @@ export interface TestSessionContext {
 	cleanup: () => void;
 }
 
+export function createTestResourceLoader(): ResourceLoader {
+	return {
+		getExtensions: () => ({ extensions: [], errors: [], runtime: createExtensionRuntime() }),
+		getSkills: () => ({ skills: [], diagnostics: [] }),
+		getPrompts: () => ({ prompts: [], diagnostics: [] }),
+		getThemes: () => ({ themes: [], diagnostics: [] }),
+		getAgentsFiles: () => ({ agentsFiles: [] }),
+		getSystemPrompt: () => undefined,
+		getAppendSystemPrompt: () => [],
+		reload: async () => {},
+	};
+}
+
 /**
  * Create an AgentSession for testing with proper setup and cleanup.
  * Use this for e2e tests that need real LLM calls.
@@ -204,7 +219,9 @@ export function createTestSession(options: TestSessionOptions = {}): TestSession
 		agent,
 		sessionManager,
 		settingsManager,
+		cwd: tempDir,
 		modelRegistry,
+		resourceLoader: createTestResourceLoader(),
 	});
 
 	// Must subscribe to enable session persistence