Gemini Batch Processing

Process large volumes of requests efficiently using Gemini Batch API through executable scripts for cost savings and high throughput.

When to Use This Skill

Use this skill when you need to:

• Process hundreds/thousands of requests
• Generate content in bulk (blogs, emails, descriptions)
• Reduce costs for high-volume tasks
• Run async jobs without blocking
• Process large datasets with AI
• Generate multiple documents at once
• Create scalable content pipelines
• Process requests that don't need real-time responses

Available Scripts

scripts/create_batch.js

Purpose: Create a batch job from a JSONL file

When to use:

• Starting any batch processing task
• Uploading multiple requests for processing
• Creating async jobs for large workloads

Key parameters:

Parameter	Description	Example
input_file	JSONL file path (required)	requests.jsonl
--model, -m	Model to use	gemini-3-flash-preview
--name, -n	Display name for job	"my-batch-job"

Output: Job name/ID to track with check_status.js

scripts/check_status.js

Purpose: Monitor batch job progress and completion

When to use:

• Checking if a batch job is complete
• Polling job status until finished
• Monitoring async job execution

Key parameters:

Parameter	Description	Example
job_name	Batch job name/ID (required)	batches/abc123
--wait, -w	Poll until completion	Flag

Output: Job status and final state

scripts/get_results.js

Purpose: Retrieve completed batch job results

When to use:

• Downloading completed batch results
• Parsing batch job output
• Extracting generated content

Key parameters:

Parameter	Description	Example
job_name	Batch job name/ID (required)	batches/abc123
--output, -o	Output file path	results.jsonl

Output: Results content or file

Workflows

Workflow 1: Basic Batch Processing

# 1. Create JSONL file
echo '{"key": "req1", "request": {"contents": [{"parts": [{"text": "Explain photosynthesis"}]}]}}' > requests.jsonl
echo '{"key": "req2", "request": {"contents": [{"parts": [{"text": "What is gravity?"}]}}]}' >> requests.jsonl

# 2. Create batch job
node scripts/create_batch.js requests.jsonl --name "science-questions"

# 3. Check status
node scripts/check_status.js <job-name> --wait

# 4. Get results
node scripts/get_results.js <job-name> --output results.jsonl

• Best for: Basic bulk processing, cost efficiency
• Typical time: Minutes to hours depending on job size

Workflow 2: Bulk Content Generation

# 1. Generate JSONL with content requests
python3 << 'EOF'
import json

topics = ["sustainable energy", "AI in healthcare", "space exploration"]
with open("content-requests.jsonl", "w") as f:
    for i, topic in enumerate(topics):
        req = {
            "key": f"blog-{i}",
            "request": {
                "contents": [{
                    "parts": [{
                        "text": f"Write a 500-word blog post about {topic}"
                    }]
                }]
            }
        }
        f.write(json.dumps(req) + "\n")
EOF

# 2. Process batch
node scripts/create_batch.js content-requests.jsonl --name "blog-posts" --model gemini-3-flash-preview
node scripts/check_status.js <job-name> --wait
node scripts/get_results.js <job-name> --output blog-posts.jsonl

• Best for: Blog generation, article creation, bulk writing
• Combines with: gemini-text for content needs

Workflow 3: Dataset Processing

# 1. Load dataset and create batch requests
python3 << 'EOF'
import json

# Your dataset
data = [
    {"product": "laptop", "features": ["fast", "lightweight"]},
    {"product": "headphones", "features": ["wireless", "noise-cancelling"]},
]

with open("product-descriptions.jsonl", "w") as f:
    for item in data:
        features = ", ".join(item["features"])
        prompt = f"Write a product description for {item['product']} with these features: {features}"
        req = {
            "key": item["product"],
            "request": {
                "contents": [{"parts": [{"text": prompt}]}]
            }
        }
        f.write(json.dumps(req) + "\n")
EOF

# 2. Process
node scripts/create_batch.js product-descriptions.jsonl
node scripts/check_status.js <job-name> --wait
node scripts/get_results.js <job-name> --output results.jsonl

• Best for: Product descriptions, dataset enrichment, bulk analysis

Workflow 4: Email Campaign Generation

# 1. Create personalized email requests
python3 << 'EOF'
import json

customers = [
    {"name": "Alice", "product": "premium plan"},
    {"name": "Bob", "product": "basic plan"},
]

with open("emails.jsonl", "w") as f:
    for cust in customers:
        prompt = f"Write a personalized email to {cust['name']} about upgrading to our {cust['product']}"
        req = {
            "key": f"email-{cust['name'].lower()}",
            "request": {
                "contents": [{"parts": [{"text": prompt}]}]
            }
        }
        f.write(json.dumps(req) + "\n")
EOF

# 2. Process batch
node scripts/create_batch.js emails.jsonl --name "email-campaign"
node scripts/check_status.js <job-name> --wait
node scripts/get_results.js <job-name> --output email-results.jsonl

• Best for: Marketing campaigns, personalized outreach
• Combines with: gemini-text for email content

Workflow 5: Async Job Monitoring

# 1. Create job
node scripts/create_batch.js large-batch.jsonl --name "big-job"

# 2. Check status periodically (non-blocking)
while true; do
    node scripts/check_status.js <job-name>
    sleep 60  # Check every minute
done

# 3. Get results when done
node scripts/get_results.js <job-name> --output final-results.jsonl

• Best for: Long-running jobs, background processing
• Use when: You don't need immediate results

Workflow 6: Cost-Optimized Bulk Processing

# 1. Use flash model for cost efficiency
node scripts/create_batch.js requests.jsonl --model gemini-3-flash-preview --name "cost-optimized"

# 2. Monitor and retrieve
node scripts/check_status.js <job-name> --wait
node scripts/get_results.js <job-name>

• Best for: High-volume, cost-sensitive applications
• Savings: Batch API typically 50%+ cheaper than real-time

Workflow 7: Multi-Stage Pipeline

# Stage 1: Generate content
node scripts/create_batch.js content-requests.jsonl --name "stage1-content"
node scripts/check_status.js <job1> --wait

# Stage 2: Summarize content
node scripts/create_batch.js summaries.jsonl --name "stage2-summaries"
node scripts/check_status.js <job2> --wait

# Stage 3: Convert to audio (gemini-tts)
# Process results from stage 2

• Best for: Complex workflows, multi-step processing
• Combines with: Other Gemini skills for complete pipelines

Parameters Reference

JSONL Format

Each line is a separate JSON object:

{
  "key": "unique-identifier",
  "request": {
    "contents": [
      {
        "parts": [
          {
            "text": "Your prompt here"
          }
        ]
      }
    ]
  }
}

Model Selection

Model	Best For	Cost	Speed
gemini-3-flash-preview	General bulk processing	Lowest	Fast
gemini-3-pro-preview	Complex reasoning tasks	Medium	Medium
gemini-2.5-flash	Stable, reliable	Low	Fast
gemini-2.5-pro	Code/math/STEM	Medium	Slow

Job States

State	Description
JOB_STATE_PENDING	Job queued, waiting to start
JOB_STATE_RUNNING	Job actively processing
JOB_STATE_SUCCEEDED	Job completed successfully
JOB_STATE_FAILED	Job failed (check error message)
JOB_STATE_CANCELLED	Job was cancelled
JOB_STATE_EXPIRED	Job timed out

Size Limits

Method	Max Size	Best For
File upload	Unlimited	Large batches (recommended)
Inline requests	<20MB	Small batches

Output Interpretation

Results JSONL

Each line contains:

{
  "key": "your-identifier",
  "response": {
    "text": "Generated content here..."
  }
}

Error Handling

• Failed requests appear in results with error information
• Check for error field in response
• Partial failures don't stop entire job

Result Access

• Use --output to save to file
• Script prints preview of results
• Parse JSONL line by line for processing

Common Issues

"google-genai not installed"

npm install @google/genai@latest dotenv@latest

"JSONL file not found"

• Verify file path is correct
• Check file extension is .jsonl (not .json)
• Use absolute paths if relative paths fail

"Invalid JSONL format"

• Each line must be valid JSON
• No trailing commas between objects
• Check for syntax errors in JSON
• Use JSON validator if unsure

"Job failed"

• Check error message in status
• Verify request format is correct
• Check model availability
• Review API quota limits

"No results found"

• Ensure job state is JOB_STATE_SUCCEEDED
• Wait for job completion before retrieving
• Check job status first with check_status.js

"Processing stuck in RUNNING state"

• Large jobs can take hours
• Use --wait flag for automated polling
• Check job size and model choice
• Contact support if stuck >24 hours

Best Practices

JSONL Creation

• Use unique keys for each request
• Validate JSON before uploading
• Test with small batch first (5-10 requests)
• Include error handling in your scripts

Job Management

• Use descriptive display names (--name)
• Save job names for tracking
• Monitor status before retrieving results
• Keep backup of original JSONL file

Performance Optimization

• Use flash models for cost efficiency
• Batch as many requests as possible
• File upload preferred over inline
• Process during off-peak hours if timing sensitive

Error Handling

• Check for failed requests in results
• Retry failed requests individually
• Log job names for audit trails
• Validate output format before use

Cost Management

• Batch API is 50%+ cheaper than real-time
• Use flash models when possible
• Monitor token usage
• Process in chunks if quota limited

Related Skills

• gemini-text: Generate individual text requests
• gemini-image: Batch image generation
• gemini-tts: Batch audio generation
• gemini-embeddings: Batch embedding creation

Quick Reference

# Basic workflow
node scripts/create_batch.js requests.jsonl
node scripts/check_status.js <job-name> --wait
node scripts/get_results.js <job-name> --output results.jsonl

# With model and name
node scripts/create_batch.js requests.jsonl --model gemini-3-flash-preview --name "my-job"

# Create JSONL programmatically
echo '{"key":"1","request":{"contents":[{"parts":[{"text":"Prompt"}]}]}}' > batch.jsonl

Reference

• Get API key: https://aistudio.google.com/apikey
• Documentation: https://ai.google.dev/gemini-api/docs/batch-processing
• JSONL: https://jsonlines.org/
• Cost savings: Batch API typically 50-90% cheaper than real-time API