ContextForge MCP Gateway

# Cached Tool Result Plugin > Author: Mihai Criveti > Version: 0.1.0 Caches idempotent tool results in-memory using a configurable key derived from tool name and selected argument fields. ## Hooks - tool_pre_invoke (advisory read: sets metadata.cache_hit) - tool_post_invoke (write-through store) ## Config ```yaml config: cacheable_tools: ["search"] ttl: 300 key_fields: search: ["q", "lang"] ``` ## Design - Pre-invoke computes a deterministic key from tool name and selected argument fields. - Pre-invoke reads the cache and annotates `metadata.cache_hit`; post-invoke writes result with TTL. - Uses in-memory dict; per-process cache suitable for small deployments or development. ## Limitations - Cannot short-circuit tool execution in pre-hook (framework constraint); orchestration must decide how to act on `cache_hit`. - In-memory cache is not shared across processes or hosts and is cleared on restart. - No size-based eviction; simple TTL expiration only. ## TODOs - Add Redis/Memcached backend and LRU/size-based eviction. - Introduce a gateway-level short-circuit mechanism for cache hits. - Configurable serialization and hashing strategies for large arguments.