AI Metadata Generation Backend Platform

Asynchronous LLM-based metadata generation system for short-form video content

Overview

Description:

An internal backend platform responsible for generating and managing metadata (titles and descriptions) for short-form video content as part of a large-scale automation pipeline.

Usage:

Used by multiple internal automation services as a post-processing step after video creation.

Environment:

Production system handling high-volume asynchronous workloads

Context

Background:

Metadata for video content was previously created manually by editors using external AI tools.

Scale:

Thousands of videos generated daily, requiring a scalable and reliable metadata generation solution.

Constraints:

  • External LLM APIs with rate limits and unstable response formats
  • High throughput requirements
  • Cost sensitivity at scale

The Challenge

Manual metadata generation became infeasible as content volume increased.

Pain Points:

  • High manual effort and long processing time
  • Inconsistent metadata quality across editors
  • Synchronous API-based approaches failing under scale and rate limits

Architecture

Pattern:

Asynchronous batch processing with message-driven orchestration

High-Level Flow:

  • 1.Scheduled job queries videos requiring metadata generation
  • 2.Video data is published to Kafka topics
  • 3.Batch workers consume messages every 3 minutes to control throughput
  • 4.Metadata is generated via LLM providers and persisted
  • 5.Downstream services retrieve metadata and track usage state

LLM Strategy

Design:

Unified abstraction layer to decouple business logic from specific LLM providers.

Features:

  • Provider prioritization via configuration
  • API key rotation to mitigate rate limits
  • Automatic fallback on timeout or invalid responses
  • Strict response format validation

Backend Responsibilities

  • Job orchestration and scheduling
  • Batch throughput control
  • Retry and failure isolation
  • Prompt optimization for cost reduction
  • Usage and consumption tracking

Performance

Throughput:

Best Case: ≈25,000 metadata records/day

Worst Case: ≈5,000 metadata records/day

Processing Model:

Batch processing every 3 minutes to balance latency and API stability

Impact

Automation:

Fully automated metadata generation at scale

Operational Benefits:

  • Significant reduction in manual workload
  • Consistent metadata quality
  • Improved system reliability under peak load

Challenges & Tradeoffs

  • Balancing throughput with external API rate limits
  • Choosing batch processing over synchronous requests for stability
  • Designing idempotent processing to safely retry failed jobs
  • Managing cost while maintaining acceptable metadata quality

Project Intel

My Role

Backend Developer

Tech Stack

JavaSpring BootKafkaPostgreSQLMultiple LLM providers

Repositories

List of Projects

AI Metadata Generation Backend Platform

01. Internal Backend Platform

AI Metadata Generation Backend Platform

AI Video Generation Backend Pipeline

02. Internal Backend Pipeline

AI Video Generation Backend Pipeline

Video Distribution & Channel Coordination Backend

03. Internal Backend Coordination System

Video Distribution & Channel Coordination Backend

Starfish Language Center Website

04. Public Website

Starfish Language Center Website

Recruitment Platform Web Application

05. Web Application

Recruitment Platform Web Application