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LangChain & Frameworks

Project: Multi-Step AI Agent

Design a multi-step agent with planning, tool use, state, verification, and stop conditions

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Project: Multi-Step AI Agent

A multi-step agent is a loop, not a magic prompt.

text
goal -> plan -> tool/action -> observe -> update -> verify -> stop

Project goal

Build an agent that can research a topic and produce a short sourced brief.

Required pieces

PiecePurpose
plannercreates steps
tool layersearch or retrieve information
memory/statetracks what is done
verifierchecks sources and claims
final writersummarizes with citations

Safety boundaries

For a first agent:

  • read-only tools only
  • max 5 tool calls
  • no external messages
  • cite sources
  • stop if evidence is missing

Success criteria

The agent succeeds when it returns:

  • answer
  • key evidence
  • citations
  • uncertainty
  • next questions

Knowledge check

Q1: Why does an agent need state?

To track progress and avoid repeating work.

Q2: What should the agent do when evidence is missing?

Stop or ask for more information, not hallucinate.