name: swarms
description: Build agents and multi-agent systems with the Swarms framework — the Agent class, tools, autonomous loops, memory, and the 15+ multi-agent architectures (SequentialWorkflow, ConcurrentWorkflow, GraphWorkflow, HierarchicalSwarm, SwarmRouter, and more). Use whenever writing, reviewing, or debugging code that imports swarms.
Swarms
Swarms is a multi-agent orchestration framework. Everything is built from one primitive — Agent — which multi-agent structures compose. This document is verified against swarms v14.0.0.
Golden rules
- Import from the top level:
from swarms import Agent, neverfrom swarms.structs.agent import Agent. The one common exception isPlannerWorkerSwarm(see below). - Every agent needs a unique
agent_name— memory files and swarm routing key on it. - Default to
max_loops=1. Use a specific integer for production. Use"auto"only for genuinely open-ended work. - Pass
tools=None, nottools=[]. An empty list breaks schema generation. - Check
examples/— 586 runnable examples live there. One is probably close to what you need. - Never set
streaming_on=Trueandstreaming_callbacktogether. Pick one.
Setup
pip install -U swarms
Set the key for whichever provider you use — any LiteLLM model string works:
export OPENAI_API_KEY="sk-..." export ANTHROPIC_API_KEY="sk-ant-..." export GROQ_API_KEY="..." export WORKSPACE_DIR="agent_workspace" # where agent state and memory land
Part 1 — The Agent
from swarms import Agent agent = Agent( agent_name="Analyst", agent_description="Analyzes market data and produces summaries.", system_prompt="You are a precise financial analyst.", model_name="gpt-5.4", max_loops=1, ) result = agent.run("Summarize the state of the semiconductor market.")
Agent.__init__ accepts 90+ parameters. These are the ones that matter:
| Parameter | Type | Default | Purpose |
|---|---|---|---|
agent_name | str | "swarm-worker-01" | Unique identity; keys memory + routing |
agent_description | str | generic | How orchestrators decide to route to it |
system_prompt | str | built-in | Persona and instructions |
model_name | str | "gpt-5.4" | Any LiteLLM model string |
max_loops | int | "auto" | 1 | Iterations, or autonomous mode |
tools | list[Callable] | None | Python functions the agent may call |
temperature | float | 0.5 | Sampling temperature |
max_tokens | int | model max | Output cap per call |
top_p | float | None | Nucleus sampling |
context_length | int | None | Token budget; triggers compression at 90% |
output_type | str | "str-all-except-first" | Return shape — see below |
streaming_on | bool | False | Stream tokens to stdout |
streaming_callback | Callable | None | Stream tokens to your function |
interactive | bool | False | REPL — prompts the user each loop |
verbose | bool | False | Debug logging |
print_on | bool | True | Print the final output |
autosave | bool | False | Persist agent state after each run |
retry_attempts | int | 3 | LLM call retries |
reasoning_effort | str | "medium" | minimal/low/medium/high/xhigh/ultra/max/none |
thinking_tokens | int | 1024 | Extended thinking budget (Claude) |
mcp_url / mcp_urls | str / list[str] | None | MCP servers to load tools from |
handoffs | list[Agent] | None | Agents this one may delegate to |
persistent_memory | bool | False | Read/write MEMORY.md across restarts |
context_compression | bool | True | Auto-summarize near the context limit |
plan_enabled | bool | False | Plan before executing |
mode | str | "standard" | "standard", "fast", "interactive" |
fallback_models | list[str] | None | Models to try if the primary fails |
output_type options: "str", "list", "dict", "json", "yaml", "xml", "final", "last", "all", "basemodel", "str-all-except-first", "dict-all-except-first", "dict-final", "list-final".
Running
agent.run(task="...") # standard agent.run(task="...", img="chart.png") # one image agent.run(task="...", imgs=["a.png", "b.png"]) # several images agent.run(task="...", n=3) # 3 independent samples await agent.arun("...") # async
Agent.run signature: run(task=None, img=None, imgs=None, correct_answer=None, streaming_callback=None, n=1).
Streaming
# To stdout agent = Agent(agent_name="Writer", model_name="gpt-5.4", streaming_on=True) agent.run("Write a haiku about distributed systems.") # To a callback (do NOT combine with streaming_on) def on_token(token: str) -> None: print(token, end="", flush=True) agent = Agent(agent_name="Writer", model_name="gpt-5.4", streaming_callback=on_token) agent.run("Write a haiku.") # Async streaming async for token in agent.arun_stream("Explain async/await."): print(token, end="", flush=True)
Part 2 — Tools
Any Python function with type hints and a docstring becomes a tool. The framework generates the OpenAI function schema automatically — the docstring is the tool description the model reads, so write it for the model.
from swarms import Agent def get_stock_price(ticker: str) -> str: """Fetch the current stock price for a ticker symbol. Args: ticker: Stock ticker symbol, e.g. 'AAPL'. Returns: The current price as a formatted string. """ import yfinance as yf return f"{ticker}: ${yf.Ticker(ticker).fast_info['last_price']:.2f}" agent = Agent( agent_name="StockAnalyst", model_name="gpt-5.4", tools=[get_stock_price], max_loops=3, # needs > 1 so it can act on the tool result ) agent.run("What are Apple and Microsoft trading at?")
max_loops must exceed 1 for tool use — loop 1 calls the tool, loop 2 uses the result.
Related knobs: tool_call_summary=True (summarize tool output), show_tool_execution_output=True (print raw returns), tool_retry_attempts (retries on tool failure).
MCP servers
agent = Agent( agent_name="MCPAgent", model_name="gpt-5.4", mcp_url="http://localhost:8000/sse", # or: mcp_urls=["http://localhost:8000/sse", "http://localhost:8001/sse"] max_loops=3, )
Inspect what a server exposes before wiring it up:
from swarms.tools.mcp_manager import MCPManager mgr = MCPManager(mcp_url="http://localhost:8000/sse") print(mgr.list_tool_names()) schemas = mgr.get_tools() # aget_tools() for the async form
Handoffs
Give an agent a roster it can delegate to. It receives a handoff_task tool automatically.
triage = Agent( agent_name="Triage", model_name="gpt-5.4", handoffs=[billing_agent, technical_agent, refunds_agent], max_loops=3, ) triage.run("My invoice is wrong and the app won't load.")
Part 3 — Autonomous mode (max_loops="auto")
The agent runs plan → execute → reflect until it decides it is finished, with 16 built-in tools available:
| Group | Tools |
|---|---|
| Planning | create_plan, think, subtask_done, complete_task, respond_to_user |
| Files | create_file, update_file, read_file, list_directory, delete_file |
| System | run_bash, grep |
| Delegation | create_sub_agent, assign_task, check_sub_agent_status, cancel_sub_agent_tasks |
agent = Agent( agent_name="Researcher", model_name="gpt-5.4", max_loops="auto", tools=[search_web], # your tools stack on top of the built-ins persistent_memory=True, context_compression=True, context_length=32000, ) agent.run("Research the top 5 vector databases and write compare.md")
Restrict the built-in set with selected_tools (default "all"):
agent = Agent( agent_name="ReadOnly", max_loops="auto", selected_tools=["create_plan", "think", "read_file", "grep", "complete_task"], )
Inspect the full list at runtime with agent.get_all_selected_tools().
⚠️ run_bash and delete_file are real. In autonomous mode the agent can modify and delete files and execute shell commands. Scope selected_tools and set WORKSPACE_DIR deliberately.
Part 4 — Memory and conversation
Persistent memory
persistent_memory=True reads {WORKSPACE_DIR}/agents/{agent_name}/MEMORY.md on startup and appends to it each response. It is off by default — set it in every process that should share the memory.
agent = Agent(agent_name="ProjectAssistant", model_name="gpt-5.4", persistent_memory=True) agent.run("My project is called Helios. Remember that.") # Later process, same agent_name and the flag set again → it remembers.
Context compression
context_compression=True (default) fires at 90% of context_length, summarizing history in place so long sessions never hit the wall. Leave it on for anything long-running.
Conversation
from swarms import Conversation conv = Conversation( name="my-conversation", # note: `name`, not `agent_name` system_prompt="You are helpful.", time_enabled=True, token_count=True, ) conv.add("user", "What is 2+2?") conv.add("assistant", "4.") conv.return_history_as_string() conv.search("2+2") conv.compact(summary="User asked arithmetic. Answer: 4.") # archives, then collapses conv.save_as_json("conv.json")
Part 5 — Multi-agent architectures
Choosing one
| Situation | Use |
|---|---|
| Single task | Agent |
| Linear A→B→C | SequentialWorkflow |
| Same task, many agents at once | ConcurrentWorkflow |
| Custom mix of sequential + parallel | AgentRearrange |
| Dependency graph / fan-out-fan-in | GraphWorkflow |
| Many models, one synthesized answer | MixtureOfAgents |
| Manager delegates to specialists | HierarchicalSwarm |
| Open discussion | GroupChat |
| Discrete decision by consensus | MajorityVoting |
| Quality-critical evaluation | CouncilAsAJudge |
| Structured adversarial debate | DebateWithJudge |
| Deep multi-stage research | HeavySwarm |
| Route each task to the best agent | MultiAgentRouter |
| Plan then execute with workers | PlannerWorkerSwarm |
| Don't know yet | SwarmRouter(swarm_type="auto") or AutoSwarmBuilder |
SequentialWorkflow
Each agent's output becomes the next agent's context.
from swarms import Agent, SequentialWorkflow pipeline = SequentialWorkflow( agents=[researcher, analyst, writer], max_loops=1, output_type="dict", ) pipeline.run("Analyze how rate hikes affect tech stocks.")
Options: team_awareness=True (agents see the roster), multi_agent_collab_prompt=True, drift_detection=True.
ConcurrentWorkflow
All agents run the same task in parallel.
from swarms import Agent, ConcurrentWorkflow workflow = ConcurrentWorkflow( agents=agents, max_workers=5, show_dashboard=True, on_error="store", # or "raise" ) workflow.run("List 10 use cases for multi-agent AI.")
AgentRearrange — flow DSL
from swarms import Agent, AgentRearrange pipeline = AgentRearrange( agents=[planner, coder, reviewer, tester], flow="Planner -> Coder -> Reviewer, Tester", max_loops=1, ) pipeline.run("Build an email validator.")
A -> B— sequential, B receives A's outputA, B— concurrent, same inputA -> B, C -> D— A, then B and C in parallel, then D on their combined output
Every name in flow must match an agent_name in agents, or it fails at run time. There is no human-in-the-loop step — split into separate .run() calls and insert your own input() between them.
GraphWorkflow — DAG
Pass agents directly to add_node/add_edge; there is no need to wrap them in Node objects.
from swarms import Agent, GraphWorkflow wf = GraphWorkflow(name="research-dag", max_loops=1) for a in (ingestion, branch_a, branch_b, merger): wf.add_node(a) wf.add_edge(ingestion, branch_a) # fan out wf.add_edge(ingestion, branch_b) wf.add_edge(branch_a, merger) # fan in wf.add_edge(branch_b, merger) wf.set_entry_points(["Ingestion"]) wf.set_end_points(["Merger"]) def on_done(node: str, result) -> None: print(f"[{node}] {len(str(result))} chars") results = wf.run(task="Analyze this dataset two ways and merge.", on_node_complete=on_done)
add_node also accepts a nested GraphWorkflow. Other options: backend="networkx"|"rustworkx", max_parallel_nodes, checkpoint_dir, streaming_callback.
SwarmRouter — one entry point
Swap architectures without rewriting orchestration.
from swarms import Agent, SwarmRouter router = SwarmRouter(agents=agents, swarm_type="SequentialWorkflow", max_loops=1) router.run("Write a post about transformers.")
Valid swarm_type values — exactly these 16:
"AgentRearrange", "MixtureOfAgents", "SequentialWorkflow", "ConcurrentWorkflow", "GroupChat", "MultiAgentRouter", "HierarchicalSwarm", "MajorityVoting", "CouncilAsAJudge", "HeavySwarm", "BatchedGridWorkflow", "LLMCouncil", "DebateWithJudge", "RoundRobin", "PlannerWorkerSwarm", "auto".
"AutoSwarmBuilder" and "SpreadSheetSwarm" are not router types — use those classes directly. With swarm_type="AgentRearrange" you must also pass rearrange_flow.
MixtureOfAgents
Workers answer independently; an aggregator synthesizes. Best with diverse providers.
from swarms import Agent, MixtureOfAgents moa = MixtureOfAgents( agents=[worker_gpt, worker_claude, worker_llama], aggregator_agent=aggregator, # optional; falls back to aggregator_model_name layers=3, max_loops=1, ) moa.run("Best practices for securing a Kubernetes cluster?")
HierarchicalSwarm
A director decomposes the task, delegates, and synthesizes results.
from swarms import Agent, HierarchicalSwarm swarm = HierarchicalSwarm( agents=[data_worker, writing_worker, review_worker], director=director, # optional; else built from director_model_name max_loops=2, planning_enabled=True, parallel_execution=True, director_feedback_on=True, ) swarm.run("Produce a competitive analysis of the AI chip market.")
Also: agent_as_judge=True, max_agent_retries, max_reassignment_attempts, interactive=True.
GroupChat
Asynchronous and self-selecting — no rounds, no speaker-selection function. Every agent scores how much it wants to speak (0–1); replies above threshold are broadcast. Ends at max_loops messages or after idle_timeout seconds of silence.
from swarms import Agent, GroupChat chat = GroupChat( agents=[optimist, pessimist, realist], # at least 2 required max_loops=10, threshold=0.5, # raise for a more selective room recency_penalty=0.3, # discourages one agent dominating idle_timeout=8.0, ) chat.run("Should we adopt AI for medical diagnosis?")
auto_equip=True (default) injects the required RESPOND_TOOL into every agent — you do not need to pass it yourself. Set auto_equip=False only if you attach RESPOND_TOOL manually via tools_list_dictionary.
MajorityVoting
Agents answer independently; a consensus agent picks the winner.
from swarms import Agent, MajorityVoting mv = MajorityVoting( agents=voters, consensus_agent_model_name="gpt-5.4", max_loops=1, ) mv.run("Python or Rust for a high-performance web server?")
CouncilAsAJudge
Evaluates a response across dimensions. It builds its own council from model names — it does not take an agents list or a judge agent.
from swarms import CouncilAsAJudge council = CouncilAsAJudge( model_name="gpt-5.4", aggregation_model_name="gpt-5.4", random_model_name=True, max_loops=1, ) council.run("Should we store biometric data on-device only?")
DebateWithJudge
from swarms import Agent, DebateWithJudge debate = DebateWithJudge( pro_agent=pro, con_agent=con, judge_agent=judge, max_loops=3, # rounds ) debate.run("Motion: open-source LLMs will surpass closed-source by 2027.")
preset_agents=True generates pro/con/judge for you from model_name. The kwargs are pro_agent/con_agent/judge_agent — not agents=[...] plus judge=.
HeavySwarm
Deep multi-stage analysis. Configured by model names, not by an agents list.
from swarms import HeavySwarm swarm = HeavySwarm( question_agent_model_name="gpt-5.4", worker_model_name="gpt-5.4", max_loops=1, timeout=900, show_dashboard=True, worker_tools=[search_web], ) swarm.run("Analyze the implications of AGI on global labour markets.")
PlannerWorkerSwarm
A planner decomposes the task and workers execute; a judge checks completion each cycle. Not exported at the top level:
from swarms.structs.planner_worker_swarm import PlannerWorkerSwarm swarm = PlannerWorkerSwarm( agents=workers, # workers only — the planner is built internally planner_model_name="gpt-5.4", judge_model_name="gpt-5.4", max_planner_depth=1, max_loops=1, ) swarm.run("Build a go-to-market strategy for a B2B SaaS product.")
Others
from swarms import ( MultiAgentRouter, # routes each task to the best-fit agent RoundRobinSwarm, # fixed rotation LLMCouncil, # members answer, rank peers anonymously, chairman synthesizes BatchedGridWorkflow, # agent i runs task i AutoSwarmBuilder, # generates the agents and architecture from a description SpreadSheetSwarm, # structured tabular processing AdvisorSwarm, SelfMoASeq, HybridHierarchicalClusterSwarm, ) builder = AutoSwarmBuilder(name="MarketResearch", description="...", max_loops=1) builder.run("Research the EV market and find growth opportunities.")
Part 6 — Execution helpers
from swarms import ( run_agents_concurrently, run_agents_with_different_tasks, run_agents_concurrently_async, batch_agent_execution, run_single_agent, aggregate, ) run_agents_concurrently(agents=agents, task="Summarize today's news.", max_workers=8) run_agents_with_different_tasks([(agent_a, "task A"), (agent_b, "task B")]) # list of tuples batch_agent_execution(agents=agents, tasks=tasks, max_workers=10) aggregate(workers=agents, task="...", aggregator_model_name="gpt-5.4")
Note run_agents_with_different_tasks takes a list of (agent, task) tuples, not a dict.
Scheduling
from swarms import CronJob job = CronJob(agent=agent, interval="10minutes", job_id="market-check") job.run(task="Check for unusual market activity.")
interval is "<number><unit>", and the unit must be one of second, seconds, minute, minutes, hour, hours. Abbreviations like "30s" raise CronJobConfigError, as does a zero interval.
Loading agents from files
from swarms import AgentLoader loader = AgentLoader(concurrent=True) agents = loader.load_agents_from_markdown("agents/") # also: _from_yaml, _from_csv agent = loader.load_agent_from_markdown("agents/researcher.md")
Part 7 — Pitfalls
| Don't | Do | Why |
|---|---|---|
from swarms.structs.agent import Agent | from swarms import Agent | Submodule paths move between versions |
tools=[] | tools=None | Empty list breaks schema generation |
tools=[f] with max_loops=1 | max_loops=3 | Loop 1 calls the tool; it needs loop 2 to use the result |
Same agent_name on several agents | Unique names | MEMORY.md is keyed on it — they corrupt each other |
streaming_on=True + streaming_callback | Pick one | They conflict |
CouncilAsAJudge(agents=..., judge=...) | Model-name kwargs | It takes no agents or judge argument |
DebateWithJudge(agents=[p, c], judge=j) | pro_agent=, con_agent=, judge_agent= | Those kwarg names don't exist |
HeavySwarm(num_agents=4, model_name=...) | question_agent_model_name=, worker_model_name= | Those kwarg names don't exist |
from swarms import PlannerWorkerSwarm | from swarms.structs.planner_worker_swarm import ... | Not exported at the top level |
swarm_type="AutoSwarmBuilder" | Use the class directly | Not one of the 16 router types |
GraphWorkflow.add_node(Node(...)) | add_node(agent) | It takes the agent itself |
| Building agents inside a loop | Build once, reuse | Construction is expensive |
context_compression=False on long runs | Leave it True | The run will hit the context wall |
Bare max_loops="auto" in production | Integer max_loops | Autonomous runs have no natural stopping point |
Production configuration
agent = Agent( agent_name="ProductionAgent", agent_description="...", model_name="gpt-5.4", max_loops=3, context_length=32000, context_compression=True, persistent_memory=True, autosave=True, retry_attempts=3, fallback_models=["claude-sonnet-4-6"], verbose=False, )
Debugging
verbose=True— full internal loggingshow_tool_execution_output=True— raw tool returnsoutput_type="all"— the complete conversation instead of just the final messageagent.get_all_selected_tools()— the autonomous tool rosteragent.short_memory.return_history_as_string()— dump the conversation
Reference
- Docs: docs.swarms.world · Agent API
- Examples:
examples/—single_agent/,multi_agent/,tools/,guides/ - Source:
swarms/structs/(agents + swarms),swarms/agents/(loops, judges, routers),swarms/tools/ - Contributing: CONTRIBUTING.md
