react.py

def ResearchAgent(props):
      phase, set_phase = use_state("research")
      sources, set_sources = use_state([])
      analyses, set_analyses = use_state({})

      if phase == "research":
          def on_done(r):
              set_sources(r["sources"])
              set_phase("analyze")

          return h(Claude, {"tools": ["web"], "on_finished": on_done},
              h(Phase, {"name": "research"},
                  h(Step, None, f"Search for recent articles about {props['topic']}"),
                  h(Step, None, "Find at least 5 credible sources"),
              )
          )

      if phase == "analyze":
          pending = [s for s in sources if s["id"] not in analyses]

          def add_analysis(source, result):
              next_analyses = {**analyses, source["id"]: result}
              set_analyses(next_analyses)
              if len(next_analyses) == len(sources):
                  set_phase("write")

          return h(Fragment, None, *[
              h(Subagent, {"key": s["id"], "name": f"analyzer-{s['id']}"},
                  h(Claude, {"on_finished": lambda r, s=s: add_analysis(s, r)},
                    f"Analyze: {s['url']}")
              )
              for s in pending
          ])

      return h(Claude, None, f"Write report from: {list(analyses.values())}")