content-pipeline

name	content-pipeline
description	AI content generation pipeline guide for SYNTHEX. Documents the model registry, provider abstraction, BYOK key injection, content scoring, and repurposing flow. Use when working on AI-powered content features or debugging model selection issues.
effort	medium
metadata	{"author":"synthex","version":"1.0","engine":"synthex-ai-agency","type":"reference-skill","triggers":["content generation","ai pipeline","model selection","openrouter","byok","api key injection","content scoring","model registry","content repurpose"]}
context	fork

Content Pipeline — AI Content Generation Guide

Purpose

SYNTHEX generates content through a multi-layer pipeline: model registry selects the right LLM, provider abstraction handles API differences, BYOK key injection uses the user's own API key when available, and content scoring evaluates quality without any AI calls.

This skill documents the full pipeline flow and the key decisions at each stage.

Pipeline Flow

User Request
  │
  ▼
ContentRequest (type, platform, tone, persona)
  │
  ▼
API Credential Injector ─── Does user have a BYOK key?
  │                           YES → Decrypt and use user's key
  │                           NO  → Use platform OPENROUTER_API_KEY
  ▼
Provider Abstraction (getAIProvider)
  │
  ├─ OpenRouter Provider (primary, supports 100+ models)
  ├─ Anthropic Provider (direct Claude access)
  ├─ Google Provider (Gemini models)
  └─ OpenRouter Provider with OpenAI keys (passthrough)
  │
  ▼
Model Registry → Select model by provider + tier
  │
  ▼
Content Generator → Build prompt with persona, platform rules
  │
  ▼
Generated Content
  │
  ▼
Content Scorer → Score across 5 dimensions (no AI call)
  │
  ▼
Content Repurposer → Adapt for multiple platforms

Model Registry

File: lib/ai/model-registry.ts Purpose: Single source of truth for which models SYNTHEX uses system-wide

Types:

• AIProvider: 'openai' | 'anthropic' | 'google' | 'openrouter'
• ModelTier: 'latest' | 'production' | 'legacy'
• ModelConfig: Full model specification (id, capabilities, cost, context window)

Key functions:

• getAllLatestModels() — Returns the latest model for each provider
• Models not in the registry are rejected by the system

Admin refresh: POST /api/system/models (owner-only) calls modelManager.forceUpdate()

Model Manager: lib/ai/model-manager.ts — Handles health monitoring, auto-failover, and periodic registry refresh.

Provider Abstraction

Files:

• lib/ai/providers/index.ts — Factory function getAIProvider()
• lib/ai/providers/base-provider.ts — Abstract base class
• lib/ai/providers/openrouter-provider.ts — OpenRouter implementation
• lib/ai/providers/anthropic-provider.ts — Anthropic (Claude) direct
• lib/ai/providers/google-provider.ts — Google (Gemini) direct

Usage:

import { getAIProvider } from '@/lib/ai/providers';

const ai = getAIProvider({ apiKey: userKey || undefined });
const response = await ai.complete({
  model: 'gpt-4-turbo',
  messages: [{ role: 'user', content: prompt }],
  temperature: 0.7,
});

Key pattern: All providers implement the same interface. The factory selects the right provider based on the model ID or explicit provider parameter.

BYOK Key Injection

File: lib/ai/api-credential-injector.ts Purpose: Bridges user-stored API credentials into AI provider calls

Flow:

1. Look up user's API credential in DB (prisma.aPICredential.findFirst)
2. Filter: isActive: true, revokedAt: null, most recent first
3. Decrypt with decryptApiKey() from lib/encryption/api-key-encryption.ts
4. Pass decrypted key to getAIProvider({ apiKey }) — overrides platform key

Provider mapping:

openrouter → openrouter
openai     → openrouter (OpenAI keys work through OpenRouter)
anthropic  → anthropic
google     → google

Security:

• Keys stored encrypted at rest (AES-256-GCM)
• Decrypted only at point of use, never logged
• revokedAt field prevents use of compromised keys

Legacy OpenRouter Client

File: lib/ai/openrouter-client.ts Purpose: Direct OpenRouter API calls (legacy — prefer provider abstraction)

Environment variables:

• OPENROUTER_API_KEY — Platform-level API key
• OPENROUTER_SITE_NAME — App name header
• OPENROUTER_SITE_URL — App URL header

When to use: Only for legacy code paths. New code should use getAIProvider().

Content Generator

File: lib/ai/content-generator.ts Purpose: Multi-model content creation with persona-based voice consistency

ContentRequest fields:

• type: post, caption, thread, story, reel, article
• platform: twitter, instagram, linkedin, tiktok, facebook, youtube
• tone: professional, casual, humorous, inspirational, educational
• personaId: Optional trained persona for voice/style consistency
• keywords, targetAudience, length, includeEmojis, includeHashtags, includeCTA

Persona integration: When personaId is provided, the generator loads the persona's tone, style, vocabulary, and emotion settings from the database and injects them into the system prompt.

Content Scorer

File: lib/ai/content-scorer.ts Purpose: Real-time content quality scoring with zero AI calls

Five dimensions (0-100 each):

Dimension	Weight	What It Measures
Engagement	30%	Hooks, questions, emojis, CTAs, conversation starters
Readability	25%	Flesch-Kincaid approximation for social content
Platform Fit	20%	Character limits, formatting patterns per platform
Clarity	15%	Jargon, passive voice, specificity
Emotional	10%	Sentiment strength, power words, urgency, storytelling

Overall score: Weighted average of all five dimensions.

Key design choice: Pure functions with no AI calls. This enables real-time scoring in the UI without latency or cost.

Content Repurposer

File: lib/ai/content-repurposer.ts Purpose: Adapts a single piece of content for multiple platforms

Takes generated content and transforms it to match each platform's format, character limits, and audience expectations.

Common Mistakes

Mistake	Why It's Wrong	Correct Pattern
Hardcoding model IDs	Breaks when models update	Use model-registry.ts
Using openrouter-client.ts directly	Bypasses provider abstraction	Use getAIProvider()
Logging decrypted API keys	Security vulnerability	Never log keys
Skipping content scoring	Inconsistent quality	Always score before publish
Ignoring persona when available	Brand voice inconsistency	Pass personaId through

Environment Variables

Variable	Purpose	Required
OPENROUTER_API_KEY	Platform-level AI API key	CRITICAL
OPENROUTER_SITE_NAME	App name for OpenRouter headers	Required
OPENROUTER_SITE_URL	App URL for OpenRouter headers	Required
ANTHROPIC_API_KEY	Direct Anthropic access	Optional
GOOGLE_AI_API_KEY	Direct Google AI access	Optional
API_ENCRYPTION_KEY	BYOK key encryption (AES-256-GCM)	CRITICAL

File Index

File	Purpose
lib/ai/model-registry.ts	Model catalogue and version tracking
lib/ai/model-manager.ts	Health monitoring, failover, auto-refresh
lib/ai/providers/index.ts	Provider factory (getAIProvider)
lib/ai/providers/base-provider.ts	Abstract provider base class
lib/ai/providers/openrouter-provider.ts	OpenRouter implementation
lib/ai/providers/anthropic-provider.ts	Anthropic (Claude) implementation
lib/ai/providers/google-provider.ts	Google (Gemini) implementation
lib/ai/api-credential-injector.ts	BYOK key lookup and decryption
lib/ai/content-generator.ts	Prompt building and content generation
lib/ai/content-scorer.ts	Real-time quality scoring (no AI calls)
lib/ai/content-repurposer.ts	Multi-platform content adaptation
lib/ai/openrouter-client.ts	Legacy OpenRouter client (prefer providers)
lib/encryption/api-key-encryption.ts	AES-256-GCM key encryption/decryption

Reference skill: This is a read-only architecture guide — it documents existing systems and does not generate creative or code output. No capability uplift block is needed.