---
title: "OpenRouter Launches Prompt Caching with Sticky Routing to Drastically Reduce Multi-Turn Costs"
source: "OpenRouter：Announcements（RSS）"
source_tier: "t1"
url: "https://openrouter.ai/blog/tutorials/prompt-caching-sticky-routing/"
permalink: "https://feed.astralor.com/items/itm_3e7ffd9cbbc829461895c81c"
published: "2026-07-21T00:00:00.000Z"
score: 92
channel: "ai"
tags: ["OpenRouter","session_id","Cost Optimization","Prompt Caching","Sticky Routing"]
---

# OpenRouter Launches Prompt Caching with Sticky Routing to Drastically Reduce Multi-Turn Costs

## AI commentary

> For developers making frequent AI API calls, this feature is a direct money-saver. Sticky routing guarantees cache hit rates, and session_id requires zero configuration—every OpenRouter user should try it immediately.

## At a glance

OpenRouter released a tutorial explaining how Prompt Caching works with Sticky Routing and session_id. Cache reads cost only 0.1x to 0.5x of input price; sticky routing ensures the same session continuously hits the cache, cutting multi-turn agent costs by over 50%. No extra configuration is needed—just pass session_id in requests—making it ideal for high-frequency, long-conversation scenarios.

## Key points

- Cache reads cost only 0.1x to 0.5x of input price, significantly reducing inference costs.
- Sticky routing ensures requests with the same session_id always hit the same cache node, boosting hit rates.
- Ideal for multi-turn agents, long conversations, and repeated prompt scenarios, saving massive API costs.

## Full text

Cache reads cost 0.1x-0.5x of input. See how prompt caching compounds with OpenRouter's sticky routing and session_id to cut multi-turn agent costs.

---

Verify against the original before citing; curated by Astral Feed: https://feed.astralor.com/items/itm_3e7ffd9cbbc829461895c81c