Chain LLM calls with tools and branching logic

import { Stack0 } from '@stack0/sdk'
 
const stack0 = new Stack0({ apiKey: process.env.STACK0_API_KEY })
 
// Build a multi-step AI pipeline
const result = await stack0.workflows.run({
  steps: [
    {
      id: 'extract',
      type: 'llm',
      model: 'gpt-4o',
      prompt: 'Extract key entities from this text: {{input.text}}',
      outputSchema: {
        people: 'string[]',
        companies: 'string[]',
        topics: 'string[]',
      },
    },
    {
      id: 'analyze',
      type: 'llm',
      model: 'gpt-4o',
      prompt: 'Analyze sentiment for each entity: {{steps.extract.output}}',
      dependsOn: ['extract'],
    },
    {
      id: 'summarize',
      type: 'llm',
      model: 'gpt-4o-mini',
      prompt: 'Write a brief summary combining: {{steps.extract.output}} and {{steps.analyze.output}}',
      dependsOn: ['extract', 'analyze'],
    },
  ],
  input: {
    text: articleContent,
  },
  onError: 'retry', // retry, skip, or abort
  maxRetries: 3,
})
 
console.log(result.steps.summarize.output)
console.log(result.usage) // { totalTokens, totalCost, durationMs }