prompt-cache

# Prompt Cache A lightweight caching layer that prevents regenerating identical content. Saved approximately 60% of API quota in production by catching duplicate prompts before they hit the API. ## How It Works 1. Normalize the prompt (lowercase, collapse whitespace) 2. Combine with context keys (user name, language, model) 3. SHA-256 hash the combined key 4. Check cache table for existing result 5. On miss: call API, store result. On hit: return cached result instantly. ## Usage ```python import prompt_cache # Check before calling expensive API cached = await prompt_cache.get_cached( prompt="Tell me a story about clouds", child_name="Sophie", language="fr" ) if cached: return cached # Free! No API call needed. # Cache miss — call the API result = await generate_story(prompt, child_name, language) # Store for next time await prompt_cache.set_cached(prompt, child_name, language, result) ``` ## Schema ```sql CREATE TABLE IF NOT EXISTS prompt_cache ( prompt_hash TEXT NOT NULL, child_name TEXT NOT NULL, language TEXT NOT NULL, story_json TEXT, created_at DATETIME DEFAULT CURRENT_TIMESTAMP, PRIMARY KEY (prompt_hash, child_name, language) ); ``` ## Adapt the Keys The default implementation uses `(prompt, child_name, language)` as the cache key. Adapt to your domain: - **Chat completions:** `(system_prompt, user_message, model)` - **TTS:** `(text, voice_id, model_id)` - **Image gen:** `(prompt, seed, model, size)` ## Files - `scripts/prompt_cache.py` — Cache implementation (35 lines)