> ## Documentation Index
> Fetch the complete documentation index at: https://praison.ai/docs/llms.txt
> Use this file to discover all available pages before exploring further.
# Loops
> Process multiple items automatically
Agents can process lists of items one by one - like handling emails, analyzing files, or transforming data.
```mermaid theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
graph LR
subgraph "Loop Processing"
A[👤 User] --> B[🤖 Agent]
B --> C[📋 Items]
C --> D[📊 Results]
end
classDef agent fill:#8B0000,color:#fff
classDef tool fill:#189AB4,color:#fff
class B agent
class A,C,D tool
```
## Quick Start
```typescript theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
import { Agent, loop } from 'praisonai';
const agent = new Agent({
instructions: 'Summarize the given text concisely'
});
const texts = [
'First article about AI...',
'Second article about robotics...',
'Third article about automation...'
];
const results = await loop(agent, { over: 'texts' }).run({ texts });
console.log(results);
// ['AI summary...', 'Robotics summary...', 'Automation summary...']
```
```typescript theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
const results = await loop(agent, {
fromCsv: './customers.csv'
}).run({});
// Each row is processed by the agent
```
***
## User Interaction Flow
```mermaid theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
sequenceDiagram
participant User
participant Agent
participant Items
User->>Agent: "Process these items"
loop For Each Item
Agent->>Items: Get next item
Items-->>Agent: Item data
Agent->>Agent: Process
end
Agent-->>User: All results
```
***
## Configuration Levels
```typescript theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
// Level 1: String - Simple field reference
const result = await loop(agent, { over: 'items' }).run({ items });
// Level 2: Dict - With options
const result = await loop(agent, {
over: 'items',
maxIterations: 100,
continueOnError: true
}).run({ items });
// Level 3: Instance - Full control with callbacks
const result = await loop(agent, {
over: 'items',
onIteration: (item, index, total) => {
console.log(`Processing ${index + 1} of ${total}`);
},
onError: (error, item) => {
console.error(`Failed: ${item}`);
}
}).run({ items });
```
***
## Data Sources
| Source | Use Case |
| ---------------------- | ----------------------------- |
| `over: 'items'` | Array in your code |
| `fromCsv: 'file.csv'` | CSV file with rows |
| `fromFile: 'list.txt'` | Text file (one item per line) |
***
## Common Examples
### Email Processing
```typescript theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
const emails = [
{ from: 'alice@example.com', body: 'Meeting request...' },
{ from: 'bob@example.com', body: 'Question about...' }
];
const responses = await loop(agent, { over: 'emails' }).run({ emails });
```
### Handle Errors Gracefully
```typescript theme={"theme":{"light":"vitesse-light","dark":"vitesse-dark"}}
const result = await loop(agent, {
over: 'items',
continueOnError: true
}).run({ items });
console.log(`Success: ${result.results.length}`);
console.log(`Failed: ${result.errors.length}`);
```
***
## API Reference
Loop class documentation
***
## Best Practices
Use `maxIterations` to prevent runaway loops. Default is 1000.
Use `continueOnError: true` to process all items even if some fail.
Use `onIteration` callback to show progress for long-running loops.
***
## Related
Multi-step workflows
Create AI agents