Workflow (Legacy) with Suspend and Resume

Workflow steps can be suspended and resumed at any point in the workflow execution. This example demonstrates how to suspend a workflow step and resume it later.

Basic ExampleDirect link to Basic Example

import { Mastra } from "@mastra/core";
import { LegacyStep, LegacyWorkflow } from "@mastra/core/workflows/legacy";
import { z } from "zod";

const stepOne = new LegacyStep({
  id: "stepOne",
  outputSchema: z.object({
    doubledValue: z.number(),
  }),
  execute: async ({ context }) => {
    const doubledValue = context.triggerData.inputValue * 2;
    return { doubledValue };
  },
});

const stepTwo = new LegacyStep({
  id: "stepTwo",
  outputSchema: z.object({
    incrementedValue: z.number(),
  }),
  execute: async ({ context, suspend }) => {
    const secondValue = context.inputData?.secondValue ?? 0;
    const doubledValue = context.getStepResult(stepOne)?.doubledValue ?? 0;

    const incrementedValue = doubledValue + secondValue;

    if (incrementedValue < 100) {
      await suspend();
      return { incrementedValue: 0 };
    }
    return { incrementedValue };
  },
});

// Build the workflow
const myWorkflow = new LegacyWorkflow({
  name: "my-workflow",
  triggerSchema: z.object({
    inputValue: z.number(),
  }),
});

// run workflows in parallel
myWorkflow.step(stepOne).then(stepTwo).commit();

// Register the workflow
export const mastra = new Mastra({
  legacy_workflows: { registeredWorkflow: myWorkflow },
});

// Get registered workflow from Mastra
const registeredWorkflow = mastra.legacy_getWorkflow("registeredWorkflow");
const { runId, start } = registeredWorkflow.createRun();

// Start watching the workflow before executing it
myWorkflow.watch(async ({ context, activePaths }) => {
  for (const _path of activePaths) {
    const stepTwoStatus = context.steps?.stepTwo?.status;
    if (stepTwoStatus === "suspended") {
      console.log("Workflow suspended, resuming with new value");

      // Resume the workflow with new context
      await myWorkflow.resume({
        runId,
        stepId: "stepTwo",
        context: { secondValue: 100 },
      });
    }
  }
});

// Start the workflow execution
await start({ triggerData: { inputValue: 45 } });

Advanced Example with Multiple Suspension Points Using async/await pattern and suspend payloadsDirect link to Advanced Example with Multiple Suspension Points Using async/await pattern and suspend payloads

This example demonstrates a more complex workflow with multiple suspension points using the async/await pattern. It simulates a content generation workflow that requires human intervention at different stages.

import { Mastra } from "@mastra/core";
import { LegacyStep, LegacyWorkflow } from "@mastra/core/workflows/legacy";
import { z } from "zod";

// Step 1: Get user input
const getUserInput = new LegacyStep({
  id: "getUserInput",
  execute: async ({ context }) => {
    // In a real application, this might come from a form or API
    return { userInput: context.triggerData.input };
  },
  outputSchema: z.object({ userInput: z.string() }),
});

// Step 2: Generate content with AI (may suspend for human guidance)
const promptAgent = new LegacyStep({
  id: "promptAgent",
  inputSchema: z.object({
    guidance: z.string(),
  }),
  execute: async ({ context, suspend }) => {
    const userInput = context.getStepResult(getUserInput)?.userInput;
    console.log(`Generating content based on: ${userInput}`);

    const guidance = context.inputData?.guidance;

    // Simulate AI generating content
    const initialDraft = generateInitialDraft(userInput);

    // If confidence is high, return the generated content directly
    if (initialDraft.confidenceScore > 0.7) {
      return { modelOutput: initialDraft.content };
    }

    console.log(
      "Low confidence in generated content, suspending for human guidance",
      { guidance },
    );

    // If confidence is low, suspend for human guidance
    if (!guidance) {
      // only suspend if no guidance is provided
      await suspend();
      return undefined;
    }

    // This code runs after resume with human guidance
    console.log("Resumed with human guidance");

    // Use the human guidance to improve the output
    return {
      modelOutput: enhanceWithGuidance(initialDraft.content, guidance),
    };
  },
  outputSchema: z.object({ modelOutput: z.string() }).optional(),
});

// Step 3: Evaluate the content quality
const evaluateTone = new LegacyStep({
  id: "evaluateToneConsistency",
  execute: async ({ context }) => {
    const content = context.getStepResult(promptAgent)?.modelOutput;

    // Simulate evaluation
    return {
      toneScore: { score: calculateToneScore(content) },
      completenessScore: { score: calculateCompletenessScore(content) },
    };
  },
  outputSchema: z.object({
    toneScore: z.any(),
    completenessScore: z.any(),
  }),
});

// Step 4: Improve response if needed (may suspend)
const improveResponse = new LegacyStep({
  id: "improveResponse",
  inputSchema: z.object({
    improvedContent: z.string(),
    resumeAttempts: z.number(),
  }),
  execute: async ({ context, suspend }) => {
    const content = context.getStepResult(promptAgent)?.modelOutput;
    const toneScore = context.getStepResult(evaluateTone)?.toneScore.score ?? 0;
    const completenessScore =
      context.getStepResult(evaluateTone)?.completenessScore.score ?? 0;

    const improvedContent = context.inputData.improvedContent;
    const resumeAttempts = context.inputData.resumeAttempts ?? 0;

    // If scores are above threshold, make minor improvements
    if (toneScore > 0.8 && completenessScore > 0.8) {
      return { improvedOutput: makeMinorImprovements(content) };
    }

    console.log(
      "Content quality below threshold, suspending for human intervention",
      { improvedContent, resumeAttempts },
    );

    if (!improvedContent) {
      // Suspend with payload containing content and resume attempts
      await suspend({
        content,
        scores: { tone: toneScore, completeness: completenessScore },
        needsImprovement: toneScore < 0.8 ? "tone" : "completeness",
        resumeAttempts: resumeAttempts + 1,
      });
      return { improvedOutput: content ?? "" };
    }

    console.log("Resumed with human improvements", improvedContent);
    return { improvedOutput: improvedContent ?? content ?? "" };
  },
  outputSchema: z.object({ improvedOutput: z.string() }).optional(),
});

// Step 5: Final evaluation
const evaluateImproved = new LegacyStep({
  id: "evaluateImprovedResponse",
  execute: async ({ context }) => {
    const improvedContent =
      context.getStepResult(improveResponse)?.improvedOutput;

    // Simulate final evaluation
    return {
      toneScore: { score: calculateToneScore(improvedContent) },
      completenessScore: { score: calculateCompletenessScore(improvedContent) },
    };
  },
  outputSchema: z.object({
    toneScore: z.any(),
    completenessScore: z.any(),
  }),
});

// Build the workflow
const contentWorkflow = new LegacyWorkflow({
  name: "content-generation-workflow",
  triggerSchema: z.object({ input: z.string() }),
});

contentWorkflow
  .step(getUserInput)
  .then(promptAgent)
  .then(evaluateTone)
  .then(improveResponse)
  .then(evaluateImproved)
  .commit();

// Register the workflow
const mastra = new Mastra({
  legacy_workflows: { contentWorkflow },
});

// Helper functions (simulated)
function generateInitialDraft(input: string = "") {
  // Simulate AI generating content
  return {
    content: `Generated content based on: ${input}`,
    confidenceScore: 0.6, // Simulate low confidence to trigger suspension
  };
}

function enhanceWithGuidance(content: string = "", guidance: string = "") {
  return `${content} (Enhanced with guidance: ${guidance})`;
}

function makeMinorImprovements(content: string = "") {
  return `${content} (with minor improvements)`;
}

function calculateToneScore(_: string = "") {
  return 0.7; // Simulate a score that will trigger suspension
}

function calculateCompletenessScore(_: string = "") {
  return 0.9;
}

// Usage example
async function runWorkflow() {
  const workflow = mastra.legacy_getWorkflow("contentWorkflow");
  const { runId, start } = workflow.createRun();

  let finalResult: any;

  // Start the workflow
  const initialResult = await start({
    triggerData: { input: "Create content about sustainable energy" },
  });

  console.log("Initial workflow state:", initialResult.results);

  const promptAgentStepResult = initialResult.activePaths.get("promptAgent");

  // Check if promptAgent step is suspended
  if (promptAgentStepResult?.status === "suspended") {
    console.log("Workflow suspended at promptAgent step");
    console.log("Suspension payload:", promptAgentStepResult?.suspendPayload);

    // Resume with human guidance
    const resumeResult1 = await workflow.resume({
      runId,
      stepId: "promptAgent",
      context: {
        guidance: "Focus more on solar and wind energy technologies",
      },
    });

    console.log("Workflow resumed and continued to next steps");

    let improveResponseResumeAttempts = 0;
    let improveResponseStatus =
      resumeResult1?.activePaths.get("improveResponse")?.status;

    // Check if improveResponse step is suspended
    while (improveResponseStatus === "suspended") {
      console.log("Workflow suspended at improveResponse step");
      console.log(
        "Suspension payload:",
        resumeResult1?.activePaths.get("improveResponse")?.suspendPayload,
      );

      const improvedContent =
        improveResponseResumeAttempts < 3
          ? undefined
          : "Completely revised content about sustainable energy focusing on solar and wind technologies";

      // Resume with human improvements
      finalResult = await workflow.resume({
        runId,
        stepId: "improveResponse",
        context: {
          improvedContent,
          resumeAttempts: improveResponseResumeAttempts,
        },
      });

      improveResponseResumeAttempts =
        finalResult?.activePaths.get("improveResponse")?.suspendPayload
          ?.resumeAttempts ?? 0;
      improveResponseStatus =
        finalResult?.activePaths.get("improveResponse")?.status;

      console.log("Improved response result:", finalResult?.results);
    }
  }
  return finalResult;
}

// Run the workflow
const result = await runWorkflow();
console.log("Workflow completed");
console.log("Final workflow result:", result);

Workflows (Legacy)Direct link to Workflows (Legacy)

The following links provide example documentation for legacy workflows: