Sim

TypeScript

The official TypeScript/JavaScript SDK for Sim provides full type safety and supports both Node.js and browser environments, allowing you to execute workflows programmatically from your Node.js applications, web applications, and other JavaScript environments.

The TypeScript SDK provides full type safety, async execution support, automatic rate limiting with exponential backoff, and usage tracking.

Installation

Install the SDK using your preferred package manager:

npm install simstudio-ts-sdk
yarn add simstudio-ts-sdk
bun add simstudio-ts-sdk

Quick Start

Here's a simple example to get you started:

import { SimStudioClient } from 'simstudio-ts-sdk';

// Initialize the client
const client = new SimStudioClient({
  apiKey: 'your-api-key-here',
  baseUrl: 'https://sim.ai' // optional, defaults to https://sim.ai
});

// Execute a workflow
try {
  const result = await client.executeWorkflow('workflow-id');
  console.log('Workflow executed successfully:', result);
} catch (error) {
  console.error('Workflow execution failed:', error);
}

API Reference

SimStudioClient

Constructor

new SimStudioClient(config: SimStudioConfig)

Configuration:

  • config.apiKey (string): Your Sim API key
  • config.baseUrl (string, optional): Base URL for the Sim API (defaults to https://sim.ai)

Methods

executeWorkflow()

Execute a workflow with optional input data.

const result = await client.executeWorkflow('workflow-id', {
  input: { message: 'Hello, world!' },
  timeout: 30000 // 30 seconds
});

Parameters:

  • workflowId (string): The ID of the workflow to execute
  • options (ExecutionOptions, optional):
    • input (any): Input data to pass to the workflow
    • timeout (number): Timeout in milliseconds (default: 30000)
    • stream (boolean): Enable streaming responses (default: false)
    • selectedOutputs (string[]): Block outputs to stream in blockName.attribute format (e.g., ["agent1.content"])
    • async (boolean): Execute asynchronously (default: false)

Returns: Promise<WorkflowExecutionResult | AsyncExecutionResult>

When async: true, returns immediately with a task ID for polling. Otherwise, waits for completion.

getWorkflowStatus()

Get the status of a workflow (deployment status, etc.).

const status = await client.getWorkflowStatus('workflow-id');
console.log('Is deployed:', status.isDeployed);

Parameters:

  • workflowId (string): The ID of the workflow

Returns: Promise<WorkflowStatus>

validateWorkflow()

Validate that a workflow is ready for execution.

const isReady = await client.validateWorkflow('workflow-id');
if (isReady) {
  // Workflow is deployed and ready
}

Parameters:

  • workflowId (string): The ID of the workflow

Returns: Promise<boolean>

getJobStatus()

Get the status of an async job execution.

const status = await client.getJobStatus('task-id-from-async-execution');
console.log('Status:', status.status); // 'queued', 'processing', 'completed', 'failed'
if (status.status === 'completed') {
  console.log('Output:', status.output);
}

Parameters:

  • taskId (string): The task ID returned from async execution

Returns: Promise<JobStatus>

Response fields:

  • success (boolean): Whether the request was successful
  • taskId (string): The task ID
  • status (string): One of 'queued', 'processing', 'completed', 'failed', 'cancelled'
  • metadata (object): Contains startedAt, completedAt, and duration
  • output (any, optional): The workflow output (when completed)
  • error (any, optional): Error details (when failed)
  • estimatedDuration (number, optional): Estimated duration in milliseconds (when processing/queued)
executeWithRetry()

Execute a workflow with automatic retry on rate limit errors using exponential backoff.

const result = await client.executeWithRetry('workflow-id', {
  input: { message: 'Hello' },
  timeout: 30000
}, {
  maxRetries: 3,           // Maximum number of retries
  initialDelay: 1000,      // Initial delay in ms (1 second)
  maxDelay: 30000,         // Maximum delay in ms (30 seconds)
  backoffMultiplier: 2     // Exponential backoff multiplier
});

Parameters:

  • workflowId (string): The ID of the workflow to execute
  • options (ExecutionOptions, optional): Same as executeWorkflow()
  • retryOptions (RetryOptions, optional):
    • maxRetries (number): Maximum number of retries (default: 3)
    • initialDelay (number): Initial delay in ms (default: 1000)
    • maxDelay (number): Maximum delay in ms (default: 30000)
    • backoffMultiplier (number): Backoff multiplier (default: 2)

Returns: Promise<WorkflowExecutionResult | AsyncExecutionResult>

The retry logic uses exponential backoff (1s → 2s → 4s → 8s...) with ±25% jitter to prevent thundering herd. If the API provides a retry-after header, it will be used instead.

getRateLimitInfo()

Get the current rate limit information from the last API response.

const rateLimitInfo = client.getRateLimitInfo();
if (rateLimitInfo) {
  console.log('Limit:', rateLimitInfo.limit);
  console.log('Remaining:', rateLimitInfo.remaining);
  console.log('Reset:', new Date(rateLimitInfo.reset * 1000));
}

Returns: RateLimitInfo | null

getUsageLimits()

Get current usage limits and quota information for your account.

const limits = await client.getUsageLimits();
console.log('Sync requests remaining:', limits.rateLimit.sync.remaining);
console.log('Async requests remaining:', limits.rateLimit.async.remaining);
console.log('Current period cost:', limits.usage.currentPeriodCost);
console.log('Plan:', limits.usage.plan);

Returns: Promise<UsageLimits>

Response structure:

{
  success: boolean
  rateLimit: {
    sync: {
      isLimited: boolean
      limit: number
      remaining: number
      resetAt: string
    }
    async: {
      isLimited: boolean
      limit: number
      remaining: number
      resetAt: string
    }
    authType: string  // 'api' or 'manual'
  }
  usage: {
    currentPeriodCost: number
    limit: number
    plan: string  // e.g., 'free', 'pro'
  }
}
setApiKey()

Update the API key.

client.setApiKey('new-api-key');
setBaseUrl()

Update the base URL.

client.setBaseUrl('https://my-custom-domain.com');

Types

WorkflowExecutionResult

interface WorkflowExecutionResult {
  success: boolean;
  output?: any;
  error?: string;
  logs?: any[];
  metadata?: {
    duration?: number;
    executionId?: string;
    [key: string]: any;
  };
  traceSpans?: any[];
  totalDuration?: number;
}

AsyncExecutionResult

interface AsyncExecutionResult {
  success: boolean;
  taskId: string;
  status: 'queued';
  createdAt: string;
  links: {
    status: string;  // e.g., "/api/jobs/{taskId}"
  };
}

WorkflowStatus

interface WorkflowStatus {
  isDeployed: boolean;
  deployedAt?: string;
  isPublished: boolean;
  needsRedeployment: boolean;
}

RateLimitInfo

interface RateLimitInfo {
  limit: number;
  remaining: number;
  reset: number;
  retryAfter?: number;
}

UsageLimits

interface UsageLimits {
  success: boolean;
  rateLimit: {
    sync: {
      isLimited: boolean;
      limit: number;
      remaining: number;
      resetAt: string;
    };
    async: {
      isLimited: boolean;
      limit: number;
      remaining: number;
      resetAt: string;
    };
    authType: string;
  };
  usage: {
    currentPeriodCost: number;
    limit: number;
    plan: string;
  };
}

SimStudioError

class SimStudioError extends Error {
  code?: string;
  status?: number;
}

Common error codes:

  • UNAUTHORIZED: Invalid API key
  • TIMEOUT: Request timed out
  • RATE_LIMIT_EXCEEDED: Rate limit exceeded
  • USAGE_LIMIT_EXCEEDED: Usage limit exceeded
  • EXECUTION_ERROR: Workflow execution failed

Examples

Basic Workflow Execution

Set up the SimStudioClient with your API key.

Check if the workflow is deployed and ready for execution.

Run the workflow with your input data.

Process the execution result and handle any errors.

import { SimStudioClient } from 'simstudio-ts-sdk';

const client = new SimStudioClient({
  apiKey: process.env.SIM_API_KEY!
});

async function runWorkflow() {
  try {
    // Check if workflow is ready
    const isReady = await client.validateWorkflow('my-workflow-id');
    if (!isReady) {
      throw new Error('Workflow is not deployed or ready');
    }

    // Execute the workflow
    const result = await client.executeWorkflow('my-workflow-id', {
      input: {
        message: 'Process this data',
        userId: '12345'
      }
    });

    if (result.success) {
      console.log('Output:', result.output);
      console.log('Duration:', result.metadata?.duration);
    } else {
      console.error('Workflow failed:', result.error);
    }
  } catch (error) {
    console.error('Error:', error);
  }
}

runWorkflow();

Error Handling

Handle different types of errors that may occur during workflow execution:

import { SimStudioClient, SimStudioError } from 'simstudio-ts-sdk';

const client = new SimStudioClient({
  apiKey: process.env.SIM_API_KEY!
});

async function executeWithErrorHandling() {
  try {
    const result = await client.executeWorkflow('workflow-id');
    return result;
  } catch (error) {
    if (error instanceof SimStudioError) {
      switch (error.code) {
        case 'UNAUTHORIZED':
          console.error('Invalid API key');
          break;
        case 'TIMEOUT':
          console.error('Workflow execution timed out');
          break;
        case 'USAGE_LIMIT_EXCEEDED':
          console.error('Usage limit exceeded');
          break;
        case 'INVALID_JSON':
          console.error('Invalid JSON in request body');
          break;
        default:
          console.error('Workflow error:', error.message);
      }
    } else {
      console.error('Unexpected error:', error);
    }
    throw error;
  }
}

Environment Configuration

Configure the client using environment variables:

import { SimStudioClient } from 'simstudio-ts-sdk';

// Development configuration
const apiKey = process.env.SIM_API_KEY;
if (!apiKey) {
  throw new Error('SIM_API_KEY environment variable is required');
}

const client = new SimStudioClient({
  apiKey,
  baseUrl: process.env.SIM_BASE_URL // optional
});
import { SimStudioClient } from 'simstudio-ts-sdk';

// Production configuration with validation
const apiKey = process.env.SIM_API_KEY;
if (!apiKey) {
  throw new Error('SIM_API_KEY environment variable is required');
}

const client = new SimStudioClient({
  apiKey,
  baseUrl: process.env.SIM_BASE_URL || 'https://sim.ai'
});

Node.js Express Integration

Integrate with an Express.js server:

import express from 'express';
import { SimStudioClient } from 'simstudio-ts-sdk';

const app = express();
const client = new SimStudioClient({
  apiKey: process.env.SIM_API_KEY!
});

app.use(express.json());

app.post('/execute-workflow', async (req, res) => {
  try {
    const { workflowId, input } = req.body;
    
    const result = await client.executeWorkflow(workflowId, {
      input,
      timeout: 60000
    });

    res.json({
      success: true,
      data: result
    });
  } catch (error) {
    console.error('Workflow execution error:', error);
    res.status(500).json({
      success: false,
      error: error instanceof Error ? error.message : 'Unknown error'
    });
  }
});

app.listen(3000, () => {
  console.log('Server running on port 3000');
});

Next.js API Route

Use with Next.js API routes:

// pages/api/workflow.ts or app/api/workflow/route.ts
import { NextApiRequest, NextApiResponse } from 'next';
import { SimStudioClient } from 'simstudio-ts-sdk';

const client = new SimStudioClient({
  apiKey: process.env.SIM_API_KEY!
});

export default async function handler(
  req: NextApiRequest,
  res: NextApiResponse
) {
  if (req.method !== 'POST') {
    return res.status(405).json({ error: 'Method not allowed' });
  }

  try {
    const { workflowId, input } = req.body;

    const result = await client.executeWorkflow(workflowId, {
      input,
      timeout: 30000
    });

    res.status(200).json(result);
  } catch (error) {
    console.error('Error executing workflow:', error);
    res.status(500).json({
      error: 'Failed to execute workflow'
    });
  }
}

Browser Usage

Use in the browser (with proper CORS configuration):

import { SimStudioClient } from 'simstudio-ts-sdk';

// Note: In production, use a proxy server to avoid exposing API keys
const client = new SimStudioClient({
  apiKey: 'your-public-api-key', // Use with caution in browser
  baseUrl: 'https://sim.ai'
});

async function executeClientSideWorkflow() {
  try {
    const result = await client.executeWorkflow('workflow-id', {
      input: {
        userInput: 'Hello from browser'
      }
    });

    console.log('Workflow result:', result);

    // Update UI with result
    document.getElementById('result')!.textContent =
      JSON.stringify(result.output, null, 2);
  } catch (error) {
    console.error('Error:', error);
  }
}

File Upload

File objects are automatically detected and converted to base64 format. Include them in your input under the field name matching your workflow's API trigger input format.

The SDK converts File objects to this format:

{
  type: 'file',
  data: 'data:mime/type;base64,base64data',
  name: 'filename',
  mime: 'mime/type'
}

Alternatively, you can manually provide files using the URL format:

{
  type: 'url',
  data: 'https://example.com/file.pdf',
  name: 'file.pdf',
  mime: 'application/pdf'
}
import { SimStudioClient } from 'simstudio-ts-sdk';

const client = new SimStudioClient({
  apiKey: process.env.NEXT_PUBLIC_SIM_API_KEY!
});

// From file input
async function handleFileUpload(event: Event) {
  const input = event.target as HTMLInputElement;
  const files = Array.from(input.files || []);

  // Include files under the field name from your API trigger's input format
  const result = await client.executeWorkflow('workflow-id', {
    input: {
      documents: files,  // Must match your workflow's "files" field name
      instructions: 'Analyze these documents'
    }
  });

  console.log('Result:', result);
}
import { SimStudioClient } from 'simstudio-ts-sdk';
import fs from 'fs';

const client = new SimStudioClient({
  apiKey: process.env.SIM_API_KEY!
});

// Read file and create File object
const fileBuffer = fs.readFileSync('./document.pdf');
const file = new File([fileBuffer], 'document.pdf', {
  type: 'application/pdf'
});

// Include files under the field name from your API trigger's input format
const result = await client.executeWorkflow('workflow-id', {
  input: {
    documents: [file],  // Must match your workflow's "files" field name
    query: 'Summarize this document'
  }
});

When using the SDK in the browser, be careful not to expose sensitive API keys. Consider using a backend proxy or public API keys with limited permissions.

React Hook Example

Create a custom React hook for workflow execution:

import { useState, useCallback } from 'react';
import { SimStudioClient, WorkflowExecutionResult } from 'simstudio-ts-sdk';

const client = new SimStudioClient({
  apiKey: process.env.SIM_API_KEY!
});

interface UseWorkflowResult {
  result: WorkflowExecutionResult | null;
  loading: boolean;
  error: Error | null;
  executeWorkflow: (workflowId: string, input?: any) => Promise<void>;
}

export function useWorkflow(): UseWorkflowResult {
  const [result, setResult] = useState<WorkflowExecutionResult | null>(null);
  const [loading, setLoading] = useState(false);
  const [error, setError] = useState<Error | null>(null);

  const executeWorkflow = useCallback(async (workflowId: string, input?: any) => {
    setLoading(true);
    setError(null);
    setResult(null);

    try {
      const workflowResult = await client.executeWorkflow(workflowId, {
        input,
        timeout: 30000
      });
      setResult(workflowResult);
    } catch (err) {
      setError(err instanceof Error ? err : new Error('Unknown error'));
    } finally {
      setLoading(false);
    }
  }, []);

  return {
    result,
    loading,
    error,
    executeWorkflow
  };
}

// Usage in component
function WorkflowComponent() {
  const { result, loading, error, executeWorkflow } = useWorkflow();

  const handleExecute = () => {
    executeWorkflow('my-workflow-id', {
      message: 'Hello from React!'
    });
  };

  return (
    <div>
      <button onClick={handleExecute} disabled={loading}>
        {loading ? 'Executing...' : 'Execute Workflow'}
      </button>

      {error && <div>Error: {error.message}</div>}
      {result && (
        <div>
          <h3>Result:</h3>
          <pre>{JSON.stringify(result, null, 2)}</pre>
        </div>
      )}
    </div>
  );
}

Async Workflow Execution

Execute workflows asynchronously for long-running tasks:

import { SimStudioClient, AsyncExecutionResult } from 'simstudio-ts-sdk';

const client = new SimStudioClient({
  apiKey: process.env.SIM_API_KEY!
});

async function executeAsync() {
  try {
    // Start async execution
    const result = await client.executeWorkflow('workflow-id', {
      input: { data: 'large dataset' },
      async: true  // Execute asynchronously
    });

    // Check if result is an async execution
    if ('taskId' in result) {
      console.log('Task ID:', result.taskId);
      console.log('Status endpoint:', result.links.status);

      // Poll for completion
      let status = await client.getJobStatus(result.taskId);

      while (status.status === 'queued' || status.status === 'processing') {
        console.log('Current status:', status.status);
        await new Promise(resolve => setTimeout(resolve, 2000)); // Wait 2 seconds
        status = await client.getJobStatus(result.taskId);
      }

      if (status.status === 'completed') {
        console.log('Workflow completed!');
        console.log('Output:', status.output);
        console.log('Duration:', status.metadata.duration);
      } else {
        console.error('Workflow failed:', status.error);
      }
    }
  } catch (error) {
    console.error('Error:', error);
  }
}

executeAsync();

Rate Limiting and Retry

Handle rate limits automatically with exponential backoff:

import { SimStudioClient, SimStudioError } from 'simstudio-ts-sdk';

const client = new SimStudioClient({
  apiKey: process.env.SIM_API_KEY!
});

async function executeWithRetryHandling() {
  try {
    // Automatically retries on rate limit
    const result = await client.executeWithRetry('workflow-id', {
      input: { message: 'Process this' }
    }, {
      maxRetries: 5,
      initialDelay: 1000,
      maxDelay: 60000,
      backoffMultiplier: 2
    });

    console.log('Success:', result);
  } catch (error) {
    if (error instanceof SimStudioError && error.code === 'RATE_LIMIT_EXCEEDED') {
      console.error('Rate limit exceeded after all retries');

      // Check rate limit info
      const rateLimitInfo = client.getRateLimitInfo();
      if (rateLimitInfo) {
        console.log('Rate limit resets at:', new Date(rateLimitInfo.reset * 1000));
      }
    }
  }
}

Usage Monitoring

Monitor your account usage and limits:

import { SimStudioClient } from 'simstudio-ts-sdk';

const client = new SimStudioClient({
  apiKey: process.env.SIM_API_KEY!
});

async function checkUsage() {
  try {
    const limits = await client.getUsageLimits();

    console.log('=== Rate Limits ===');
    console.log('Sync requests:');
    console.log('  Limit:', limits.rateLimit.sync.limit);
    console.log('  Remaining:', limits.rateLimit.sync.remaining);
    console.log('  Resets at:', limits.rateLimit.sync.resetAt);
    console.log('  Is limited:', limits.rateLimit.sync.isLimited);

    console.log('\nAsync requests:');
    console.log('  Limit:', limits.rateLimit.async.limit);
    console.log('  Remaining:', limits.rateLimit.async.remaining);
    console.log('  Resets at:', limits.rateLimit.async.resetAt);
    console.log('  Is limited:', limits.rateLimit.async.isLimited);

    console.log('\n=== Usage ===');
    console.log('Current period cost: $' + limits.usage.currentPeriodCost.toFixed(2));
    console.log('Limit: $' + limits.usage.limit.toFixed(2));
    console.log('Plan:', limits.usage.plan);

    const percentUsed = (limits.usage.currentPeriodCost / limits.usage.limit) * 100;
    console.log('Usage: ' + percentUsed.toFixed(1) + '%');

    if (percentUsed > 80) {
      console.warn('⚠️  Warning: You are approaching your usage limit!');
    }
  } catch (error) {
    console.error('Error checking usage:', error);
  }
}

checkUsage();

Streaming Workflow Execution

Execute workflows with real-time streaming responses:

import { SimStudioClient } from 'simstudio-ts-sdk';

const client = new SimStudioClient({
  apiKey: process.env.SIM_API_KEY!
});

async function executeWithStreaming() {
  try {
    // Enable streaming for specific block outputs
    const result = await client.executeWorkflow('workflow-id', {
      input: { message: 'Count to five' },
      stream: true,
      selectedOutputs: ['agent1.content'] // Use blockName.attribute format
    });

    console.log('Workflow result:', result);
  } catch (error) {
    console.error('Error:', error);
  }
}

The streaming response follows the Server-Sent Events (SSE) format:

data: {"blockId":"7b7735b9-19e5-4bd6-818b-46aae2596e9f","chunk":"One"}

data: {"blockId":"7b7735b9-19e5-4bd6-818b-46aae2596e9f","chunk":", two"}

data: {"event":"done","success":true,"output":{},"metadata":{"duration":610}}

data: [DONE]

React Streaming Example:

import { useState, useEffect } from 'react';

function StreamingWorkflow() {
  const [output, setOutput] = useState('');
  const [loading, setLoading] = useState(false);

  const executeStreaming = async () => {
    setLoading(true);
    setOutput('');

    // IMPORTANT: Make this API call from your backend server, not the browser
    // Never expose your API key in client-side code
    const response = await fetch('https://sim.ai/api/workflows/WORKFLOW_ID/execute', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'X-API-Key': process.env.SIM_API_KEY! // Server-side environment variable only
      },
      body: JSON.stringify({
        message: 'Generate a story',
        stream: true,
        selectedOutputs: ['agent1.content']
      })
    });

    const reader = response.body?.getReader();
    const decoder = new TextDecoder();

    while (reader) {
      const { done, value } = await reader.read();
      if (done) break;

      const chunk = decoder.decode(value);
      const lines = chunk.split('\n\n');

      for (const line of lines) {
        if (line.startsWith('data: ')) {
          const data = line.slice(6);
          if (data === '[DONE]') {
            setLoading(false);
            break;
          }

          try {
            const parsed = JSON.parse(data);
            if (parsed.chunk) {
              setOutput(prev => prev + parsed.chunk);
            } else if (parsed.event === 'done') {
              console.log('Execution complete:', parsed.metadata);
            }
          } catch (e) {
            // Skip invalid JSON
          }
        }
      }
    }
  };

  return (
    <div>
      <button onClick={executeStreaming} disabled={loading}>
        {loading ? 'Generating...' : 'Start Streaming'}
      </button>
      <div style={{ whiteSpace: 'pre-wrap' }}>{output}</div>
    </div>
  );
}

Getting Your API Key

Navigate to Sim and log in to your account.

Navigate to the workflow you want to execute programmatically.

Click on "Deploy" to deploy your workflow if it hasn't been deployed yet.

During the deployment process, select or create an API key.

Copy the API key to use in your TypeScript/JavaScript application.

Requirements

  • Node.js 16+
  • TypeScript 5.0+ (for TypeScript projects)

License

Apache-2.0

Python
On this page

On this page

Installation
Quick Start
API Reference
SimStudioClient
Constructor
Methods
executeWorkflow()
getWorkflowStatus()
validateWorkflow()
getJobStatus()
executeWithRetry()
getRateLimitInfo()
getUsageLimits()
setApiKey()
setBaseUrl()
Types
WorkflowExecutionResult
AsyncExecutionResult
WorkflowStatus
RateLimitInfo
UsageLimits
SimStudioError
Examples
Basic Workflow Execution
Error Handling
Environment Configuration
Node.js Express Integration
Next.js API Route
Browser Usage
File Upload
React Hook Example
Async Workflow Execution
Rate Limiting and Retry
Usage Monitoring
Streaming Workflow Execution
Getting Your API Key
Requirements
License