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Documentation Index

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Use this file to discover all available pages before exploring further.

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Method Signature

browser.agent(config: OpensteerAgentConfig): OpensteerAgentInstance
Create an agent instance for autonomous browser control using AI models with computer use capabilities.

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Configuration

​
mode
OpensteerAgentMode
required
Agent mode. Currently only 'cua' (Computer Use Agent) is supported.
​
model
string | OpensteerAgentModelConfig
Model configuration. Can be a model string in provider/model format or a detailed configuration object.String format: 'provider/model'Examples:
  • 'openai/computer-use-preview'
  • 'anthropic/claude-3-5-sonnet-20241022'
  • 'google/gemini-2.0-flash-exp'
Object format: See Model Configuration below.
​
systemPrompt
string
Custom system prompt to guide agent behavior. Defaults to:
You are a browser automation agent. Complete the user instruction 
safely and efficiently. Do not ask follow-up questions. Finish 
as soon as the task is complete.
​
waitBetweenActionsMs
number
default:500
Milliseconds to wait between agent actions. Must be a non-negative number. Set to 0 for no delay.

​
Model Configuration

When using the object format for model, provide an OpensteerAgentModelConfig:
​
modelName
string
required
Model name in provider/model format. Must include a slash separator.Examples:
  • 'openai/computer-use-preview'
  • 'anthropic/claude-3-5-sonnet-20241022'
  • 'google/gemini-2.0-flash-exp'
​
apiKey
string
API key for the provider. If not provided, reads from environment variables:
  • OpenAI: OPENAI_API_KEY
  • Anthropic: ANTHROPIC_API_KEY
  • Google: GOOGLE_GENERATIVE_AI_API_KEY, GEMINI_API_KEY, or GOOGLE_API_KEY
​
baseUrl
string
Custom base URL for the provider API. Useful for proxies or compatible services.
​
organization
string
Organization ID for OpenAI (if applicable).
​
thinkingBudget
number
Thinking budget for OpenAI extended reasoning models. Controls the amount of reasoning tokens allocated.
​
environment
string
Environment identifier for Google models (provider-specific configuration).

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Return Value

Returns an OpensteerAgentInstance with:
​
execute
function
required
Execute method for running agent tasks. See execute() for details.
execute(instructionOrOptions: string | OpensteerAgentExecuteOptions): Promise<OpensteerAgentResult>

​
Examples

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Simple String Model

import { Opensteer } from 'opensteer'

const browser = new Opensteer()
await browser.launch()

const agent = browser.agent({
  mode: 'cua',
  model: 'openai/computer-use-preview'
})

const result = await agent.execute('Navigate to the pricing page')
await browser.close()

​
OpenAI with Custom Configuration

const agent = browser.agent({
  mode: 'cua',
  model: {
    modelName: 'openai/computer-use-preview',
    apiKey: process.env.OPENAI_API_KEY,
    organization: 'org-123456',
    thinkingBudget: 10000
  },
  systemPrompt: 'You are a precise automation agent. Always verify actions before executing.',
  waitBetweenActionsMs: 1000
})

​
Anthropic Configuration

const agent = browser.agent({
  mode: 'cua',
  model: {
    modelName: 'anthropic/claude-3-5-sonnet-20241022',
    apiKey: process.env.ANTHROPIC_API_KEY
  },
  systemPrompt: 'Complete tasks efficiently with minimal steps.',
  waitBetweenActionsMs: 500
})

const result = await agent.execute('Search for documentation')
console.log('Provider:', result.provider) // 'anthropic'
console.log('Model:', result.model) // 'anthropic/claude-3-5-sonnet-20241022'

​
Google Gemini Configuration

const agent = browser.agent({
  mode: 'cua',
  model: {
    modelName: 'google/gemini-2.0-flash-exp',
    apiKey: process.env.GOOGLE_GENERATIVE_AI_API_KEY,
    environment: 'production'
  },
  waitBetweenActionsMs: 300
})

​
Custom Base URL (Proxy or Compatible Service)

const agent = browser.agent({
  mode: 'cua',
  model: {
    modelName: 'openai/computer-use-preview',
    apiKey: process.env.CUSTOM_API_KEY,
    baseUrl: 'https://custom-proxy.example.com/v1'
  }
})

​
Using Environment Variables Only

// Set environment variables:
// export OPENAI_API_KEY=sk-...

const agent = browser.agent({
  mode: 'cua',
  model: 'openai/computer-use-preview'
  // API key read automatically from OPENAI_API_KEY
})

​
No Wait Between Actions

const agent = browser.agent({
  mode: 'cua',
  model: 'anthropic/claude-3-5-sonnet-20241022',
  waitBetweenActionsMs: 0 // Execute actions as fast as possible
})

​
Provider-Specific Notes

​
OpenAI

  • Requires OPENAI_API_KEY environment variable or apiKey in config
  • Supports organization for team/org accounts
  • Extended reasoning models support thinkingBudget parameter
  • Model example: 'openai/computer-use-preview'

​
Anthropic

  • Requires ANTHROPIC_API_KEY environment variable or apiKey in config
  • Claude models with computer use capabilities
  • Model example: 'anthropic/claude-3-5-sonnet-20241022'

​
Google

  • Requires GOOGLE_GENERATIVE_AI_API_KEY, GEMINI_API_KEY, or GOOGLE_API_KEY
  • Supports environment parameter for environment-specific configuration
  • Gemini models with multimodal capabilities
  • Model example: 'google/gemini-2.0-flash-exp'

​
Error Handling

Configuration errors throw specific error types: 
try {
  const agent = browser.agent({
    mode: 'cua',
    model: 'invalid-provider/model'
  })
} catch (error) {
  if (error.name === 'OpensteerAgentProviderError') {
    console.error('Unsupported provider')
  } else if (error.name === 'OpensteerAgentConfigError') {
    console.error('Configuration error:', error.message)
  }
}

​
Notes

  • Only one agent execution can run at a time per agent instance
  • Agent instances are tied to the browser instance they’re created from
  • Model format must always be provider/model with a forward slash
  • API keys are required either via config or environment variables
  • The system prompt significantly affects agent behavior and decision-making
  • Higher waitBetweenActionsMs values improve reliability but slow execution

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