deepset
Haystack
Python framework for composable LLM pipelines and tool-using agents, often used for RAG.
Install
Run in your terminal
pip install haystack-ai
Latest version read from pypi package haystack-ai.
Multi-agent patterns
Handoffs
One agent passes the conversation to another agent, which takes over.
Not shown in the docs.
Subagents / agents as tools
A main agent calls other agents like tools and gets their result back, each with its own context.
How Haystack does itGraph or workflow
You define steps and edges (or a workflow), and the framework runs agents and functions through them.
How Haystack does itGroup chat / crew
Several agents with roles work together on a task, coordinated by a manager or a selection rule.
Not shown in the docs.
Human in the loop
The run pauses for a person to approve, edit or answer before it continues.
How Haystack does itProtocols and hosting
Hosted runtime
Self-hosted only (none documented)
Questions
Does Haystack support MCP?
Yes. Haystack's documentation shows agents using tools from MCP servers.
Does Haystack support the A2A protocol?
Its documentation does not cover A2A as of 2026-10-07.
What multi-agent patterns does Haystack support?
The docs show: subagents / agents as tools, graph or workflow, human in the loop.
Links
Alternatives in the same languages
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Reviewed Oct 7, 2026.