Using LangCache for Building Agents.
And no, it's not from LangChain. Itโs from Redis, built for production-scale memory and recall.
LangChainโs in-built caching mostly works on exact text matches. Redis LangCache, in contrast, uses semantic caching; it recalls based on meaning, not identical strings.
Hereโs how it works under the hood:
>A user sends a prompt to your AI app.
>Your app sends the prompt to LangCache via: POST /v1/caches/{cacheId}/entries/search
>It calls an embedding model to generate a vector for the prompt.
>It searches the cache for a semantically similar entry using those embeddings.
>If a match is found (cache hit): LangCache returns the cached response instantly.
>If no match is found (cache miss): Your app calls the LLM, gets a new response, then stores it back via: POST /v1/caches/{cacheId}/entries
>LangCache saves the new embedding and response for future reuse.
How It Differs from LangChain Caching:
>LangChainโs built-in caches (like RedisCache or InMemoryCache) work only on exact string matches.
>RedisSemanticCache supports embeddings, but itโs self-hosted and limited in scale.
>Redis LangCache is a fully managed semantic caching service designed for production workloads.
Why it matters :
>Faster response times
>Reduced API costs
>No infrastructure management
>Language-agnostic (via REST API)
When to use it :
>AI agents, RAG systems, & chatbots
>Repetitive or similar query handling
>Production-grade reliability
>Auto-optimized embeddings
>Detailed cache monitoring