fix(cli): remove side-effect from agent:end state updater (#133) (#147)

Co-authored-by: Jason Woltje <jason@diversecanvas.com>
Co-committed-by: Jason Woltje <jason@diversecanvas.com>

apps/gateway/src/agent/agent.service.ts

@@ -1,6 +1,7 @@
 import { Inject, Injectable, Logger, type OnModuleDestroy } from '@nestjs/common';
 import {
   createAgentSession,
+  DefaultResourceLoader,
   SessionManager,
   type AgentSession as PiAgentSession,
   type AgentSessionEvent,
@@ -27,6 +28,27 @@ import type { SessionInfoDto } from './session.dto.js';
 export interface AgentSessionOptions {
   provider?: string;
   modelId?: string;
+  /**
+   * Sandbox working directory for the session.
+   * File, git, and shell tools will be restricted to this directory.
+   * Falls back to AGENT_FILE_SANDBOX_DIR env var or process.cwd().
+   */
+  sandboxDir?: string;
+  /**
+   * Platform-level system prompt for this session.
+   * Merged with skill prompt additions (platform prompt first, then skills).
+   * Falls back to AGENT_SYSTEM_PROMPT env var when omitted.
+   */
+  systemPrompt?: string;
+  /**
+   * Explicit allowlist of tool names available in this session.
+   * When set, only listed tools are registered with the agent.
+   * When omitted for non-admin users, falls back to AGENT_USER_TOOLS env var.
+   * Admins (isAdmin=true) always receive the full tool set unless explicitly restricted.
+   */
+  allowedTools?: string[];
+  /** Whether the requesting user has admin privileges. Controls default tool access. */
+  isAdmin?: boolean;
 }
 
 export interface AgentSession {
@@ -41,6 +63,10 @@ export interface AgentSession {
   channels: Set<string>;
   /** System prompt additions injected from enabled prompt-type skills. */
   skillPromptAdditions: string[];
+  /** Resolved sandbox directory for this session. */
+  sandboxDir: string;
+  /** Tool names available in this session, or null when all tools are available. */
+  allowedTools: string[] | null;
 }
 
 @Injectable()
@@ -49,8 +75,6 @@ export class AgentService implements OnModuleDestroy {
   private readonly sessions = new Map<string, AgentSession>();
   private readonly creating = new Map<string, Promise<AgentSession>>();
 
-  private readonly customTools: ToolDefinition[];
-
   constructor(
     @Inject(ProviderService) private readonly providerService: ProviderService,
     @Inject(BRAIN) private readonly brain: Brain,
@@ -59,21 +83,49 @@ export class AgentService implements OnModuleDestroy {
     @Inject(CoordService) private readonly coordService: CoordService,
     @Inject(McpClientService) private readonly mcpClientService: McpClientService,
     @Inject(SkillLoaderService) private readonly skillLoaderService: SkillLoaderService,
-  ) {
-    const fileBaseDir = process.env['AGENT_FILE_SANDBOX_DIR'] ?? process.cwd();
-    const gitDefaultCwd = process.env['AGENT_GIT_CWD'] ?? process.cwd();
-    const shellDefaultCwd = process.env['AGENT_SHELL_CWD'] ?? process.cwd();
+  ) {}
 
-    this.customTools = [
-      ...createBrainTools(brain),
-      ...createCoordTools(coordService),
-      ...createMemoryTools(memory, embeddingService.available ? embeddingService : null),
-      ...createFileTools(fileBaseDir),
-      ...createGitTools(gitDefaultCwd),
-      ...createShellTools(shellDefaultCwd),
+  /**
+   * Build the full set of custom tools scoped to the given sandbox directory.
+   * Brain/coord/memory/web tools are stateless with respect to cwd; file/git/shell
+   * tools receive the resolved sandboxDir so they operate within the sandbox.
+   */
+  private buildToolsForSandbox(sandboxDir: string): ToolDefinition[] {
+    return [
+      ...createBrainTools(this.brain),
+      ...createCoordTools(this.coordService),
+      ...createMemoryTools(
+        this.memory,
+        this.embeddingService.available ? this.embeddingService : null,
+      ),
+      ...createFileTools(sandboxDir),
+      ...createGitTools(sandboxDir),
+      ...createShellTools(sandboxDir),
       ...createWebTools(),
     ];
-    this.logger.log(`Registered ${this.customTools.length} custom tools`);
+  }
+
+  /**
+   * Resolve the tool allowlist for a session.
+   * - Admin users: all tools unless an explicit allowedTools list is passed.
+   * - Regular users: use allowedTools if provided, otherwise parse AGENT_USER_TOOLS env var.
+   * Returns null when all tools should be available.
+   */
+  private resolveAllowedTools(isAdmin: boolean, allowedTools?: string[]): string[] | null {
+    if (allowedTools !== undefined) {
+      return allowedTools.length === 0 ? [] : allowedTools;
+    }
+    if (isAdmin) {
+      return null; // admins get everything
+    }
+    const envTools = process.env['AGENT_USER_TOOLS'];
+    if (!envTools) {
+      return null; // no restriction configured
+    }
+    return envTools
+      .split(',')
+      .map((t) => t.trim())
+      .filter((t) => t.length > 0);
   }
 
   async createSession(sessionId: string, options?: AgentSessionOptions): Promise<AgentSession> {
@@ -98,8 +150,15 @@ export class AgentService implements OnModuleDestroy {
     const providerName = model?.provider ?? 'default';
     const modelId = model?.id ?? 'default';
 
+    // Resolve sandbox directory: option > env var > process.cwd()
+    const sandboxDir =
+      options?.sandboxDir ?? process.env['AGENT_FILE_SANDBOX_DIR'] ?? process.cwd();
+
+    // Resolve allowed tool set
+    const allowedTools = this.resolveAllowedTools(options?.isAdmin ?? false, options?.allowedTools);
+
     this.logger.log(
-      `Creating agent session: ${sessionId} (provider=${providerName}, model=${modelId})`,
+      `Creating agent session: ${sessionId} (provider=${providerName}, model=${modelId}, sandbox=${sandboxDir}, tools=${allowedTools === null ? 'all' : allowedTools.join(',') || 'none'})`,
     );
 
     // Load skill tools from the catalog
@@ -114,21 +173,53 @@ export class AgentService implements OnModuleDestroy {
       );
     }
 
-    // Combine static tools with dynamically discovered MCP client tools
+    // Build per-session tools scoped to the sandbox directory
+    const sandboxTools = this.buildToolsForSandbox(sandboxDir);
+
+    // Combine static tools with dynamically discovered MCP client tools and skill tools
     const mcpTools = this.mcpClientService.getToolDefinitions();
-    const allCustomTools = [...this.customTools, ...skillMetaTools, ...mcpTools];
+    let allCustomTools = [...sandboxTools, ...skillMetaTools, ...mcpTools];
     if (mcpTools.length > 0) {
       this.logger.log(`Attaching ${mcpTools.length} MCP client tool(s) to session ${sessionId}`);
     }
 
+    // Filter tools by allowlist when a restriction is in effect
+    if (allowedTools !== null) {
+      const allowedSet = new Set(allowedTools);
+      const before = allCustomTools.length;
+      allCustomTools = allCustomTools.filter((t) => allowedSet.has(t.name));
+      this.logger.log(
+        `Tool restriction applied: ${allCustomTools.length}/${before} tools allowed for session ${sessionId}`,
+      );
+    }
+
+    // Build system prompt: platform prompt + skill additions appended
+    const platformPrompt = options?.systemPrompt ?? process.env['AGENT_SYSTEM_PROMPT'] ?? undefined;
+    const appendSystemPrompt =
+      promptAdditions.length > 0 ? promptAdditions.join('\n\n') : undefined;
+
+    // Construct a resource loader that injects the configured system prompt
+    const resourceLoader = new DefaultResourceLoader({
+      cwd: sandboxDir,
+      noExtensions: true,
+      noSkills: true,
+      noPromptTemplates: true,
+      noThemes: true,
+      systemPrompt: platformPrompt,
+      appendSystemPrompt: appendSystemPrompt,
+    });
+    await resourceLoader.reload();
+
     let piSession: PiAgentSession;
     try {
       const result = await createAgentSession({
         sessionManager: SessionManager.inMemory(),
         modelRegistry: this.providerService.getRegistry(),
         model: model ?? undefined,
+        cwd: sandboxDir,
         tools: [],
         customTools: allCustomTools,
+        resourceLoader,
       });
       piSession = result.session;
     } catch (err) {
@@ -162,6 +253,8 @@ export class AgentService implements OnModuleDestroy {
       promptCount: 0,
       channels: new Set(),
       skillPromptAdditions: promptAdditions,
+      sandboxDir,
+      allowedTools,
     };
 
     this.sessions.set(sessionId, session);