Swarm-TS (TypeScript version of Swarm)

A TypeScript implementation of Swarm, an educational framework exploring ergonomic, lightweight multi-agent orchestration.

[!WARNING] Swarm-TS is a TypeScript port of the original Swarm framework by OpenAI. It is currently experimental and intended for educational purposes. It is not officially supported by OpenAI and should not be used in production environments.

The primary goal of Swarm-TS is to provide a TypeScript version of the patterns explored in the Orchestrating Agents: Handoffs & Routines cookbook. It is not meant as a standalone library, and is primarily for educational purposes.

Install

Requires Node.js 14+

npm install swarm-ts

Usage

import { Swarm, Agent } from "swarm-ts";

const client = new Swarm();

function transferToAgentB(): Agent {
  return agentB;
}

const agentA = new Agent(
  (name = "Agent A"),
  (instructions = "You are a helpful agent."),
  (functions = [transferToAgentB])
);

const agentB = new Agent(
  (name = "Agent B"),
  (instructions = "Only speak in Haikus.")
);

const response = await client.run(
  (agent = agentA),
  (messages = [{ role: "user", content: "I want to talk to agent B." }])
);

console.log(response.messages[response.messages.length - 1].content);

Hope glimmers brightly,
New paths converge gracefully,
What can I assist?

Table of Contents

• Overview
• Examples
• Documentation
  • Running Swarm
  • Agents
  • Functions
  • Streaming
• Evaluations
• Utils

Overview

Swarm focuses on making agent coordination and execution lightweight, highly controllable, and easily testable.

It accomplishes this through two primitive abstractions: Agents and handoffs. An Agent encompasses instructions and tools, and can at any point choose to hand off a conversation to another Agent.

These primitives are powerful enough to express rich dynamics between tools and networks of agents, allowing you to build scalable, real-world solutions while avoiding a steep learning curve.

[!NOTE] Swarm Agents are not related to Assistants in the Assistants API. They are named similarly for convenience, but are otherwise completely unrelated. Swarm is entirely powered by the Chat Completions API and is hence stateless between calls.

Why Swarm

Swarm explores patterns that are lightweight, scalable, and highly customizable by design. Approaches similar to Swarm are best suited for situations dealing with a large number of independent capabilities and instructions that are difficult to encode into a single prompt.

The Assistants API is a great option for developers looking for fully-hosted threads and built in memory management and retrieval. However, Swarm is an educational resource for developers curious to learn about multi-agent orchestration. Swarm runs (almost) entirely on the client and, much like the Chat Completions API, does not store state between calls.

Examples

Check out /examples for inspiration! Learn more about each one in its README.

• basic: Simple examples of fundamentals like setup, function calling, handoffs, and context variables
• triage_agent: Simple example of setting up a basic triage step to hand off to the right agent
• weather_agent: Simple example of function calling
• airline: A multi-agent setup for handling different customer service requests in an airline context.
• support_bot: A customer service bot which includes a user interface agent and a help center agent with several tools
• personal_shopper: A personal shopping agent that can help with making sales and refunding orders

Documentation

Running Swarm

Start by instantiating a Swarm client (which internally just instantiates an OpenAI client).

import { Swarm } from "swarm-ts";

const client = new Swarm();

client.run()

Swarm's run() function is analogous to the chat.completions.create() function in the Chat Completions API – it takes messages and returns messages and saves no state between calls. Importantly, however, it also handles Agent function execution, hand-offs, context variable references, and can take multiple turns before returning to the user.

At its core, Swarm's client.run() implements the following loop:

1. Get a completion from the current Agent
2. Execute tool calls and append results
3. Switch Agent if necessary
4. Update context variables, if necessary
5. If no new function calls, return

Arguments

| Argument | Type | Description | Default | | --------------------- | ------- | ------------------------------------------------------------------------------------------------------------------------------------------------------ | -------------- | | agent | Agent | The (initial) agent to be called. | (required) | | messages | List | A list of message objects, identical to Chat Completions messages | (required) | | context_variables | dict | A dictionary of additional context variables, available to functions and Agent instructions | {} | | max_turns | int | The maximum number of conversational turns allowed | float("inf") | | model_override | str | An optional string to override the model being used by an Agent | None | | execute_tools | bool | If False, interrupt execution and immediately returns tool_calls message when an Agent tries to call a function | True | | stream | bool | If True, enables streaming responses | False | | debug | bool | If True, enables debug logging | False |

Once client.run() is finished (after potentially multiple calls to agents and tools) it will return a Response containing all the relevant updated state. Specifically, the new messages, the last Agent to be called, and the most up-to-date context_variables. You can pass these values (plus new user messages) in to your next execution of client.run() to continue the interaction where it left off – much like chat.completions.create(). (The run_demo_loop function implements an example of a full execution loop in /swarm/repl/repl.py.)

Response Fields

| Field | Type | Description | | --------------------- | ------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | messages | List | A list of message objects generated during the conversation. Very similar to Chat Completions messages, but with a sender field indicating which Agent the message originated from. | | agent | Agent | The last agent to handle a message. | | context_variables | dict | The same as the input variables, plus any changes. |

Agents

An Agent simply encapsulates a set of instructions with a set of functions (plus some additional settings below), and has the capability to hand off execution to another Agent.

While it's tempting to personify an Agent as "someone who does X", it can also be used to represent a very specific workflow or step defined by a set of instructions and functions (e.g. a set of steps, a complex retrieval, single step of data transformation, etc). This allows Agents to be composed into a network of "agents", "workflows", and "tasks", all represented by the same primitive.

Agent Fields

| Field | Type | Description | Default | | ---------------- | ------------------------ | ----------------------------------------------------------------------------- | ---------------------------- | | name | str | The name of the agent. | "Agent" | | model | str | The model to be used by the agent. | "gpt-4o" | | instructions | str or func() -> str | Instructions for the agent, can be a string or a callable returning a string. | "You are a helpful agent." | | functions | List | A list of functions that the agent can call. | [] | | tool_choice | str | The tool choice for the agent, if any. | None |

Instructions

Agent instructions are directly converted into the system prompt of a conversation (as the first message). Only the instructions of the active Agent will be present at any given time (e.g. if there is an Agent handoff, the system prompt will change, but the chat history will not.)

const agent = new Agent((instructions = "You are a helpful agent."));

The instructions can either be a regular str, or a function that returns a str. The function can optionally receive a context_variables parameter, which will be populated by the context_variables passed into client.run().

function instructions(context_variables: Record<string, string>): string {
  const user_name = context_variables["user_name"];
  return `Help the user, ${user_name}, do whatever they want.`;
}

const agent = new Agent((instructions = instructions));
const response = await client.run(
  (agent = agent),
  (messages = [{ role: "user", content: "Hi!" }]),
  (context_variables = { user_name: "John" })
);
console.log(response.messages[response.messages.length - 1].content);

Hi John, how can I assist you today?

Functions

• Swarm Agents can call python functions directly.
• Function should usually return a str (values will be attempted to be cast as a str).
• If a function returns an Agent, execution will be transferred to that Agent.
• If a function defines a context_variables parameter, it will be populated by the context_variables passed into client.run().

function greet(
  context_variables: Record<string, string>,
  language: string
): string {
  const user_name = context_variables["user_name"];
  const greeting = language.toLowerCase() === "spanish" ? "Hola" : "Hello";
  console.log(`${greeting}, ${user_name}!`);
  return "Done";
}

const agent = new Agent((functions = [greet]));

await client.run(
  (agent = agent),
  (messages = [{ role: "user", content: "Usa greet() por favor." }]),
  (context_variables = { user_name: "John" })
);

Hola, John!

• If an Agent function call has an error (missing function, wrong argument, error) an error response will be appended to the chat so the Agent can recover gracefully.
• If multiple functions are called by the Agent, they will be executed in that order.

Handoffs and Updating Context Variables

An Agent can hand off to another Agent by returning it in a function.

const sales_agent = new Agent((name = "Sales Agent"));

function transferToSales(): Agent {
  return sales_agent;
}

const agent = new Agent((functions = [transferToSales]));

const response = await client.run(agent, [
  { role: "user", content: "Transfer me to sales." },
]);
console.log(response.agent.name);

Sales Agent

It can also update the context_variables by returning a more complete Result object. This can also contain a value and an agent, in case you want a single function to return a value, update the agent, and update the context variables (or any subset of the three).

const sales_agent = new Agent((name = "Sales Agent"));

function talkToSales(): Result {
  console.log("Hello, World!");
  return new Result(
    (value = "Done"),
    (agent = sales_agent),
    (context_variables = { department: "sales" })
  );
}

const agent = new Agent((functions = [talkToSales]));

const response = await client.run(
  (agent = agent),
  (messages = [{ role: "user", content: "Transfer me to sales" }]),
  (context_variables = { user_name: "John" })
);
console.log(response.agent.name);
console.log(response.context_variables);

Sales Agent
{'department': 'sales', 'user_name': 'John'}

[!NOTE] If an Agent calls multiple functions to hand-off to an Agent, only the last handoff function will be used.

Function Schemas

Swarm automatically converts functions into a JSON Schema that is passed into Chat Completions tools.

• Docstrings are turned into the function description.
• Parameters without default values are set to required.
• Type hints are mapped to the parameter's type (and default to string).
• Per-parameter descriptions are not explicitly supported, but should work similarly if just added in the docstring. (In the future docstring argument parsing may be added.)

function greet(name: string, age: number, location: string = "New York"): void {
   """Greets the user. Make sure to get their name and age before calling.

   Args:
      name: Name of the user.
      age: Age of the user.
      location: Best place on earth.
   """
   console.log(`Hello ${name}, glad you are ${age} in ${location}!`);
}

{
   "type": "function",
   "function": {
      "name": "greet",
      "description": "Greets the user. Make sure to get their name and age before calling.\n\nArgs:\n   name: Name of the user.\n   age: Age of the user.\n   location: Best place on earth.",
      "parameters": {
         "type": "object",
         "properties": {
            "name": {"type": "string"},
            "age": {"type": "integer"},
            "location": {"type": "string"}
         },
         "required": ["name", "age"]
      }
   }
}

Streaming

const stream = await client.run(agent, messages, (stream = true));
for (const chunk of stream) {
  console.log(chunk);
}

Uses the same events as Chat Completions API streaming. See processAndPrintStreamingResponse in /swarm/repl/repl.ts as an example.

Two new event types have been added:

• {"delim":"start"} and {"delim":"end"}, to signal each time an Agent handles a single message (response or function call). This helps identify switches between Agents.
• {"response": Response} will return a Response object at the end of a stream with the aggregated (complete) response, for convenience.

Evaluations

Evaluations are crucial to any project, and we encourage developers to bring their own eval suites to test the performance of their swarms. For reference, we have some examples for how to eval swarm in the airline, weather_agent and triage_agent quickstart examples. See the READMEs for more details.

Utils

Use the runDemoLoop to test out your swarm! This will run a REPL on your command line. Supports streaming.

import { runDemoLoop } from "swarm-ts";
...
runDemoLoop(agent, stream=true);

Core Contributors

• Ilan Bigio - ibigio
• James Hills - jhills20
• Shyamal Anadkat - shyamal-anadkat
• Charu Jaiswal - charuj
• Colin Jarvis - colin-openai
• Katia Gil Guzman - katia-openai