defineAgent()

Helper to define an agent with type checking.

Signature

function defineAgent(config: {
  name: string;
  description: string;
  prompt: string;
  tools?: ToolDef[];
  handoffs?: string[];
  model?: string;
  mcpServers?: Record<string, McpServerConfig>;
}): AgentDef

Parameters

Property	Type	Required	Description
name	string	Yes	Unique identifier for the agent
description	string	Yes	Human-readable description (shown to other agents during handoffs)
prompt	string	Yes	System prompt for the LLM
tools	ToolDef[]	No	Tools available to this agent
handoffs	string[]	No	Names of agents this agent can hand off to
model	string	No	Model override (provider-specific)
mcpServers	Record<string, McpServerConfig>	No	MCP server configurations

Returns

AgentDef — the agent definition object.

Example

import { defineAgent } from "one-agent-sdk";

const agent = defineAgent({
  name: "researcher",
  description: "Research agent that searches the web",
  prompt: "You are a research assistant. Use tools to find information.",
  tools: [searchTool],
  handoffs: ["math", "writer"],
});