Agent loop

<div class="demo"><div class="head"><b>AGENT LOOP</b><span id="iteration">turn 1</span></div><div class="loop"><div class="node" id="reason"><small>01</small> DECIDE</div><div class="arrow">→</div><div class="node" id="tool"><small>02</small> TOOL</div><div class="arrow">→</div><div class="node" id="observe"><small>03</small> OBSERVE</div><div class="arrow">→</div><div class="node" id="answer"><small>04</small> ANSWER</div></div><div class="output" id="output">Choose a next action</div><div class="foot"><span>goal → action → result → next step</span><span>tap to step</span></div></div>

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const ids=['reason','tool','observe','answer'],messages=['Choose a next action','Call search(query)','Observe: 3 results','Respond with evidence'];let step=0,turn=1;function advance(){ids.forEach((id,i)=>document.getElementById(id).classList.toggle('on',i===step));document.getElementById('output').textContent=messages[step];document.getElementById('iteration').textContent='turn '+turn;if(step===3)turn++;step=(step+1)%4}advance();const timer=setInterval(advance,850);document.querySelector('.demo').addEventListener('pointerdown',()=>{clearInterval(timer);advance()})