DurableAgent

import { DurableAgent } from "@workflow/ai/agent";
import { getWritable } from "workflow";
import { z } from "zod";
import type { UIMessageChunk } from "ai";

async function getWeather({ city }: { city: string }) {
  "use step";

  return `Weather in ${city} is sunny`;
}

async function myAgent() {
  "use workflow";

  const agent = new DurableAgent({
    model: "anthropic/claude-haiku-4.5",
    system: "You are a helpful weather assistant.",
    temperature: 0.7,
    tools: {
      getWeather: {
        description: "Get weather for a city",
        inputSchema: z.object({ city: z.string() }),
        execute: getWeather,
      },
    },
  });

  // The agent will stream its output to the workflow
  // run's default output stream
  const writable = getWritable<UIMessageChunk>();

  const result = await agent.stream({
    messages: [{ role: "user", content: "How is the weather in San Francisco?" }],
    writable,
  });

  // result contains messages, steps, and optional structured output
  console.log(result.messages);
}

import { DurableAgent } from "@workflow/ai/agent";
import { getWritable } from "workflow";
import { z } from "zod";
import type { UIMessageChunk } from "ai";

async function getWeather({ location }: { location: string }) {
  "use step";
  // Fetch weather data
  const response = await fetch(`https://api.weather.com?location=${location}`);
  return response.json();
}

async function weatherAgentWorkflow(userQuery: string) {
  "use workflow";

  const agent = new DurableAgent({
    model: "anthropic/claude-haiku-4.5",
    tools: {
      getWeather: {
        description: "Get current weather for a location",
        inputSchema: z.object({ location: z.string() }),
        execute: getWeather,
      },
    },
    system: "You are a helpful weather assistant. Always provide accurate weather information.",
  });

  await agent.stream({
    messages: [
      {
        role: "user",
        content: userQuery,
      },
    ],
    writable: getWritable<UIMessageChunk>(),
  });
}

import { DurableAgent } from "@workflow/ai/agent";
import { getWritable } from "workflow";
import { z } from "zod";
import type { UIMessageChunk } from "ai";

async function getWeather({ location }: { location: string }) {
  "use step";
  return `Weather in ${location}: Sunny, 72°F`;
}

async function searchEvents({ location, category }: { location: string; category: string }) {
  "use step";
  return `Found 5 ${category} events in ${location}`;
}

async function multiToolAgentWorkflow(userQuery: string) {
  "use workflow";

  const agent = new DurableAgent({
    model: "anthropic/claude-haiku-4.5",
    tools: {
      getWeather: {
        description: "Get weather for a location",
        inputSchema: z.object({ location: z.string() }),
        execute: getWeather,
      },
      searchEvents: {
        description: "Search for upcoming events in a location",
        inputSchema: z.object({ location: z.string(), category: z.string() }),
        execute: searchEvents,
      },
    },
  });

  await agent.stream({
    messages: [
      {
        role: "user",
        content: userQuery,
      },
    ],
    writable: getWritable<UIMessageChunk>(),
  });
}

import { DurableAgent } from "@workflow/ai/agent";
import { z } from "zod";

async function searchProducts({ query }: { query: string }) {
  "use step";
  // Search product database
  return `Found 3 products matching "${query}"`;
}

async function multiTurnAgentWorkflow() {
  "use workflow";

  const agent = new DurableAgent({
    model: "anthropic/claude-haiku-4.5",
    tools: {
      searchProducts: {
        description: "Search for products",
        inputSchema: z.object({ query: z.string() }),
        execute: searchProducts,
      },
    },
  });

  const writable = getWritable<UIMessageChunk>();

  // First user message
  //   - Result is streamed to the provided `writable` stream
  //   - Message history is returned in `messages` for LLM context
  let { messages } = await agent.stream({
    messages: [
      { role: "user", content: "Find me some laptops" }
    ],
    writable,
  });

  // Continue the conversation with the accumulated message history
  const result = await agent.stream({
    messages: [
      ...messages,
      { role: "user", content: "Which one has the best battery life?" }
    ],
    writable,
  });

  // result.messages now contains the complete conversation history
  return result.messages;
}

import { DurableAgent } from "@workflow/ai/agent";
import { sleep, defineHook, getWritable } from "workflow";
import { z } from "zod";
import type { UIMessageChunk } from "ai";

// Define a reusable hook type
const approvalHook = defineHook<{ approved: boolean; reason: string }>();

async function scheduleTask({ delaySeconds }: { delaySeconds: number }) {
  // Note: No "use step" for this tool call,
  // since `sleep()` is a workflow level function
  await sleep(`${delaySeconds}s`);
  return `Slept for ${delaySeconds} seconds`;
}

async function requestApproval({ message }: { message: string }) {
  // Note: No "use step" for this tool call either,
  // since hooks are awaited at the workflow level

  // Utilize a Hook for Human-in-the-loop approval
  const hook = approvalHook.create({
    metadata: { message }
  });

  console.log(`Approval needed - token: ${hook.token}`);

  // Wait for the approval payload
  const approval = await hook;

  if (approval.approved) {
    return `Request approved: ${approval.reason}`;
  } else {
    throw new Error(`Request denied: ${approval.reason}`);
  }
}

async function agentWithLibraryFeaturesWorkflow(userRequest: string) {
  "use workflow";

  const agent = new DurableAgent({
    model: "anthropic/claude-haiku-4.5",
    tools: {
      scheduleTask: {
        description: "Pause the workflow for the specified number of seconds",
        inputSchema: z.object({
          delaySeconds: z.number(),
        }),
        execute: scheduleTask,
      },
      requestApproval: {
        description: "Request approval for an action",
        inputSchema: z.object({ message: z.string() }),
        execute: requestApproval,
      },
    },
  });

  await agent.stream({
    messages: [{ role: "user", content: userRequest }],
    writable: getWritable<UIMessageChunk>(),
  });
}

import { DurableAgent } from "@workflow/ai/agent";
import { getWritable } from "workflow";
import type { UIMessageChunk } from "ai";

async function agentWithPrepareStep(userMessage: string) {
  "use workflow";

  const agent = new DurableAgent({
    model: "openai/gpt-4.1-mini", // Default model
    system: "You are a helpful assistant.",
  });

  await agent.stream({
    messages: [{ role: "user", content: userMessage }],
    writable: getWritable<UIMessageChunk>(),
    prepareStep: async ({ stepNumber, messages }) => {
      // Switch to a stronger model for complex reasoning after initial steps
      if (stepNumber > 2 && messages.length > 10) {
        return {
          model: "anthropic/claude-sonnet-4.5",
        };
      }

      // Trim context if messages grow too large
      if (messages.length > 20) {
        return {
          messages: [
            messages[0], // Keep system message
            ...messages.slice(-10), // Keep last 10 messages
          ],
        };
      }

      return {}; // No changes
    },
  });
}

import { DurableAgent } from "@workflow/ai/agent";
import { getWritable, defineHook } from "workflow";
import type { UIMessageChunk } from "ai";

const messageHook = defineHook<{ message: string }>();

async function agentWithMessageQueue(initialMessage: string) {
  "use workflow";

  const messageQueue: Array<{ role: "user"; content: string }> = [];

  // Listen for incoming messages via hook
  const hook = messageHook.create();
  hook.then(({ message }) => {
    messageQueue.push({ role: "user", content: message });
  });

  const agent = new DurableAgent({
    model: "anthropic/claude-haiku-4.5",
    system: "You are a helpful assistant.",
  });

  await agent.stream({
    messages: [{ role: "user", content: initialMessage }],
    writable: getWritable<UIMessageChunk>(),
    prepareStep: ({ messages }) => {
      // Inject queued messages before the next step
      if (messageQueue.length > 0) {
        const newMessages = messageQueue.splice(0);
        return {
          messages: [
            ...messages,
            ...newMessages.map(m => ({
              role: m.role,
              content: [{ type: "text" as const, text: m.content }],
            })),
          ],
        };
      }
      return {};
    },
  });
}

import { DurableAgent } from "@workflow/ai/agent";
import { getWritable } from "workflow";
import type { UIMessageChunk } from "ai";

async function agentWithGenerationSettings() {
  "use workflow";

  // Set default generation settings in constructor
  const agent = new DurableAgent({
    model: "anthropic/claude-haiku-4.5",
    temperature: 0.7,
    maxOutputTokens: 2000,
    topP: 0.9,
  });

  // Override settings per-stream call
  await agent.stream({
    messages: [{ role: "user", content: "Write a creative story" }],
    writable: getWritable<UIMessageChunk>(),
    temperature: 0.9, // More creative for this call
    maxSteps: 1,
  });

  // Use different settings for a different task
  await agent.stream({
    messages: [{ role: "user", content: "Summarize this document precisely" }],
    writable: getWritable<UIMessageChunk>(),
    temperature: 0.1, // More deterministic
    maxSteps: 1,
  });
}

import { DurableAgent } from "@workflow/ai/agent";
import { getWritable } from "workflow";
import { z } from "zod";
import type { UIMessageChunk } from "ai";

async function searchWeb({ query }: { query: string }) {
  "use step";
  return `Results for "${query}": ...`;
}

async function analyzeResults({ data }: { data: string }) {
  "use step";
  return `Analysis: ${data}`;
}

async function multiStepAgent() {
  "use workflow";

  const agent = new DurableAgent({
    model: "anthropic/claude-haiku-4.5",
    tools: {
      searchWeb: {
        description: "Search the web for information",
        inputSchema: z.object({ query: z.string() }),
        execute: searchWeb,
      },
      analyzeResults: {
        description: "Analyze search results",
        inputSchema: z.object({ data: z.string() }),
        execute: analyzeResults,
      },
    },
  });

  // Limit to 10 steps for safety on complex research tasks
  const result = await agent.stream({
    messages: [{ role: "user", content: "Research the latest AI trends and provide an analysis" }],
    writable: getWritable<UIMessageChunk>(),
    maxSteps: 10,
  });

  // Access step-by-step details
  console.log(`Completed in ${result.steps.length} steps`);
}

import { DurableAgent } from "@workflow/ai/agent";
import { getWritable } from "workflow";
import type { UIMessageChunk } from "ai";

async function agentWithCallbacks() {
  "use workflow";

  const agent = new DurableAgent({
    model: "anthropic/claude-haiku-4.5",
  });

  await agent.stream({
    messages: [{ role: "user", content: "Hello!" }],
    writable: getWritable<UIMessageChunk>(),
    maxSteps: 5,

    // Called after each step completes
    onStepFinish: async (step) => {
      console.log(`Step finished: ${step.finishReason}`);
      console.log(`Tokens used: ${step.usage.totalTokens}`);
    },

    // Called when streaming completes
    onFinish: async ({ steps, messages }) => {
      console.log(`Completed with ${steps.length} steps`);
      console.log(`Final message count: ${messages.length}`);
    },

    // Called on errors
    onError: async ({ error }) => {
      console.error("Stream error:", error);
    },
  });
}

import { DurableAgent, Output } from "@workflow/ai/agent";
import { getWritable } from "workflow";
import { z } from "zod";
import type { UIMessageChunk } from "ai";

async function agentWithStructuredOutput() {
  "use workflow";

  const agent = new DurableAgent({
    model: "anthropic/claude-haiku-4.5",
  });

  const result = await agent.stream({
    messages: [{ role: "user", content: "Analyze the sentiment of: 'I love this product!'" }],
    writable: getWritable<UIMessageChunk>(),
    experimental_output: Output.object({
      schema: z.object({
        sentiment: z.enum(["positive", "negative", "neutral"]),
        confidence: z.number().min(0).max(1),
        reasoning: z.string(),
      }),
    }),
  });

  // Access the parsed structured output
  console.log(result.experimental_output);
  // { sentiment: "positive", confidence: 0.95, reasoning: "..." }
}

import { DurableAgent } from "@workflow/ai/agent";
import { getWritable } from "workflow";
import { z } from "zod";
import type { UIMessageChunk } from "ai";

async function agentWithToolChoice() {
  "use workflow";

  const agent = new DurableAgent({
    model: "anthropic/claude-haiku-4.5",
    tools: {
      calculator: {
        description: "Perform calculations",
        inputSchema: z.object({ expression: z.string() }),
        execute: async ({ expression }) => `Calculated: ${expression}`,
      },
      search: {
        description: "Search for information",
        inputSchema: z.object({ query: z.string() }),
        execute: async ({ query }) => `Results for: ${query}`,
      },
    },
    toolChoice: "auto", // Default: model decides
  });

  // Force the model to use a tool
  await agent.stream({
    messages: [{ role: "user", content: "What is 2 + 2?" }],
    writable: getWritable<UIMessageChunk>(),
    toolChoice: "required",
    maxSteps: 2,
  });

  // Prevent tool usage
  await agent.stream({
    messages: [{ role: "user", content: "Just chat with me" }],
    writable: getWritable<UIMessageChunk>(),
    toolChoice: "none",
  });

  // Force a specific tool
  await agent.stream({
    messages: [{ role: "user", content: "Calculate something" }],
    writable: getWritable<UIMessageChunk>(),
    toolChoice: { type: "tool", toolName: "calculator" },
    maxSteps: 2,
  });

  // Limit available tools for this call
  await agent.stream({
    messages: [{ role: "user", content: "Just search, don't calculate" }],
    writable: getWritable<UIMessageChunk>(),
    activeTools: ["search"],
    maxSteps: 2,
  });
}

import { DurableAgent } from "@workflow/ai/agent";
import { getWritable } from "workflow";
import { z } from "zod";
import type { UIMessageChunk } from "ai";

interface UserContext {
  userId: string;
  permissions: string[];
}

async function agentWithContext(userId: string) {
  "use workflow";

  const agent = new DurableAgent({
    model: "anthropic/claude-haiku-4.5",
    tools: {
      getUserData: {
        description: "Get user data",
        inputSchema: z.object({}),
        execute: async (_, { experimental_context }) => {
          const ctx = experimental_context as UserContext;
          return { userId: ctx.userId, permissions: ctx.permissions };
        },
      },
    },
  });

  await agent.stream({
    messages: [{ role: "user", content: "What are my permissions?" }],
    writable: getWritable<UIMessageChunk>(),
    maxSteps: 2,
    experimental_context: {
      userId,
      permissions: ["read", "write"],
    } as UserContext,
  });
}