Core Concepts

1import { Agent } from '@strands-agents/sdk'
2 
3const agent = new Agent({
4  systemPrompt: 'You are a helpful assistant.',
5})

1import { Agent, BedrockModel } from '@strands-agents/sdk'
2 
3const model = new BedrockModel({
4  region: 'us-east-1',
5  modelId: 'anthropic.claude-3-5-sonnet-20240620-v1:0',
6  maxTokens: 4096,
7  temperature: 0.7
8})
9 
10const agent = new Agent({ model })

1import { Agent } from '@strands-agents/sdk'
2import { OpenAIModel } from '@strands-agents/sdk/openai'
3 
4// Automatically uses process.env.OPENAI_API_KEY and defaults to gpt-4o
5const model = new OpenAIModel()
6 
7const agent = new Agent({ model })

1const agent = new Agent()
2 
3console.log('Agent response stream:')
4for await (const event of agent.stream('Tell me a story about a brave toaster.')) {
5  console.log('[Event]', event.type)
6}

1import { Agent, tool } from '@strands-agents/sdk'
2import { z } from 'zod'
3 
4const weatherTool = tool({
5  name: 'get_weather',
6  description: 'Get the current weather for a specific location.',
7  inputSchema: z.object({
8    location: z.string().describe('The city and state, e.g., San Francisco, CA'),
9  }),
10  callback: (input) => {
11    // input is fully typed based on the Zod schema
12    return `The weather in ${input.location} is 72°F and sunny.`
13  },
14})
15 
16const agent = new Agent({
17  tools: [weatherTool],
18})
19 
20await agent.invoke('What is the weather in San Francisco?')

1import { Agent } from '@strands-agents/sdk'
2import { z } from 'zod'
3 
4const PersonSchema = z.object({
5  name: z.string().describe('Name of the person'),
6  age: z.number().describe('Age of the person'),
7  occupation: z.string().describe('Occupation of the person')
8})
9 
10// Configure structured output at the agent level
11const agent = new Agent({ 
12  structuredOutputSchema: PersonSchema 
13})
14 
15const result = await agent.invoke('John Smith is a 30 year-old software engineer')
16 
17// result.structuredOutput is fully typed based on the schema
18console.log(result.structuredOutput.name) // "John Smith"
19console.log(result.structuredOutput.age)  // 30

1import { StructuredOutputException } from '@strands-agents/sdk'
2 
3try {
4  const result = await agent.invoke('Extract person info...')
5  console.log(result.structuredOutput)
6} catch (error) {
7  if (error instanceof StructuredOutputException) {
8    console.error('Validation failed:', error.message)
9  }
10}

1import { Agent, McpClient } from "@strands-agents/sdk";
2import { StdioClientTransport } from "@modelcontextprotocol/sdk/client/stdio.js";
3 
4// Create a client for a local MCP server
5const documentationTools = new McpClient({
6  transport: new StdioClientTransport({
7    command: "uvx",
8    args: ["awslabs.aws-documentation-mcp-server@latest"],
9  }),
10});
11 
12const agent = new Agent({
13  systemPrompt: "You are a helpful assistant using MCP tools.",
14  tools: [documentationTools], // Pass the MCP client directly as a tool source
15});
16 
17await agent.invoke("Use a random tool from the MCP server.");
18 
19await documentationTools.disconnect();