Full-Code · Orchestration Frameworksactive

OpenManus

Type: full-code · Vendor: FoundationAgents (MetaGPT team) · Language: Python · License: MIT · Status: active · Status in practice: experimental

Links: homepage repo

Provide an open, no-invite-code clone of the Manus general AI agent that combines a ReAct tool-calling loop with browser-use, code execution, and MCP tools.

Description. OpenManus is FoundationAgents' (the MetaGPT team's) open-source clone of the Manus general AI agent. The architecture is a class hierarchy of agents: a base ReActAgent defines the think/act loop, ToolCallAgent layers tool dispatch with a default max_steps budget of 30, and the headline Manus agent is a versatile general-purpose agent with PythonExecute, BrowserUseTool, StrReplaceEditor, AskHuman, and Terminate tools plus support for remote MCP tools over SSE and stdio. The project explicitly credits anthropic-computer-use, browser-use, and crawl4ai for foundational support.

Agent loop shape. ReAct think/act loop. The base ReActAgent defines an async step() that calls think() (decide whether to act) then act() (execute the decided action). ToolCallAgent fills in the loop with a ToolCollection and a max_steps cap (default 30); Manus narrows max_steps to 20 and wires in PythonExecute, BrowserUseTool, StrReplaceEditor, AskHuman, Terminate, plus dynamically discovered MCP tools.

Primary use cases

general-purpose tool-using agent without an invite code
browser automation via browser-use
code execution and data analysis (DataAnalysis Agent)
MCP-connected agent with remote tool servers

flowchart TD USER[User goal] --> MANUS[Manus agent<br/>max_steps=20] MANUS --> RA[ReActAgent.step] RA --> THINK[think] THINK -->|act?| ACT[act] ACT --> TOOLS{ToolCollection} TOOLS --> PY[PythonExecute] TOOLS --> BROWSER[BrowserUseTool<br/>browser-use] TOOLS --> EDITOR[StrReplaceEditor] TOOLS --> ASK[AskHuman] TOOLS --> TERM[Terminate] TOOLS --> MCP[(MCP servers<br/>SSE + stdio)] MCP -.dynamic tools.-> TOOLS ACT --> OBS[Observation] OBS --> RA RA -.max_steps reached.-> STOP[Stop] TERM -.special tool.-> FIN[Finished state] MANUS -.alt flow.-> DA[DataAnalysis Agent]

Key concepts

ReActAgent → react (docs) — Abstract base class defining the async think → act loop.
ToolCallAgent → tool-use (docs) — Concrete ReAct agent layering tool dispatch with a ToolCollection and a default max_steps of 30.
Manus agent (docs) — Versatile general-purpose agent wiring PythonExecute, BrowserUseTool, StrReplaceEditor, AskHuman, Terminate and MCP tools; max_steps=20.
MCP clients (SSE + stdio) → mcp (docs) — Manus connects to remote MCP servers over both SSE and stdio and dynamically adds discovered tools.
max_steps budget → step-budget (docs) — Each agent enforces a hard step budget; default 30 in ToolCallAgent, 20 in Manus.
DataAnalysis Agent (docs) — Multi-agent flow alternative tailored for data analysis and visualisation tasks.