rohitg00/ai-engineering-from-scratch · error · Error

Coordinator: agents must not be empty

Error message

Coordinator: agents must not be empty

What it means

Error "Coordinator: agents must not be empty" thrown in rohitg00/ai-engineering-from-scratch.

Source

Thrown at phases/19-capstone-projects/10-multi-agent-software-team/code/ts/src/coordinator.ts:17

import { Agent, CoderAgent, PlannerAgent, ReviewerAgent } from "./agent.js";
import type { Message, Role, RunResult, WorkspaceFile } from "./types.js";
import { SharedWorkspace } from "./workspace.js";

export class Coordinator {
  private readonly agents: Agent[];
  private readonly workspace = new SharedWorkspace();
  private rotationIndex = 0;

  constructor(agents?: Agent[]) {
    const resolved = agents ?? [
      new PlannerAgent(),
      new CoderAgent(),
      new ReviewerAgent(),
    ];
    if (resolved.length === 0) {
      throw new Error("Coordinator: agents must not be empty");
    }
    this.agents = resolved;
  }

  private routeTo(agent: Agent, msg: Message): boolean {
    return msg.to === "broadcast" || msg.to === agent.role;
  }

  rotation(): Role[] {
    const start = this.rotationIndex % this.agents.length;
    return this.agents
      .map((a, i) => this.agents[(start + i) % this.agents.length]!.role);
  }

  run(initialMessage: Message, maxTurns = 12): RunResult {
    let pending: Message | null = initialMessage;
    this.workspace.appendMessage(initialMessage);
    let turn = 0;

View on GitHub (pinned to 39ea8a1c6d)

When it happens

Trigger: Thrown at phases/19-capstone-projects/10-multi-agent-software-team/code/ts/src/coordinator.ts:17 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of rohitg00/ai-engineering-from-scratch@39ea8a1c6d (2026-08-26). Data as JSON: /api/errors/c2339498e25f201b. Report an issue: GitHub.