July 1, 2026
Robot diary or robot hoarder?
Show HN: PMB – local memory for coding agents that shows if it is used
This AI memory tool promises less forgetting, but commenters want a full showdown first
TLDR: PMB is a new tool that gives coding AIs a local memory on your own computer so they can remember past decisions and lessons. Commenters liked the idea but immediately demanded proof, comparisons, and reassurance that the AI won’t just remember a bunch of useless junk.
A new Show HN project called PMB is selling a very relatable dream: an AI coding helper that finally remembers what happened last time. The pitch is simple enough for non-experts: instead of your coding assistant acting like it has goldfish brain every session, PMB stores project notes, decisions, and lessons on your own computer in one local file. No cloud, no sign-up circus, no mystery data trail. It even shows you whether those saved memories are actually being used, which is the kind of accountability people suddenly want from their software and maybe their coworkers.
But the real fireworks were in the reactions. One commenter basically said, “Cool, but I’m begging for a memory arena,” calling for a giant public battle royale where the hundreds of AI memory tools get ranked against each other and against plain old default tools. That was the hottest mood in the thread: not anti-PMB, but deeply tired of the endless flood of “this fixes AI memory” claims. Another person chimed in with the practical fear everyone secretly has: what if all this extra remembering just turns into digital clutter and buries the useful stuff under nonsense? In other words, is this a brain boost or just hoarding for robots?
There wasn’t a full-on flame war, but there was definitely that classic Hacker News energy: cautious excitement mixed with spreadsheet-brained skepticism. The jokes wrote themselves — the AI has memory now, but the crowd still has trust issues.
Key Points
- •PMB is presented as a local-first, open-source memory system for coding agents that stores memory in a user-owned SQLite file.
- •The article says PMB integrates with coding tools through MCP and supports agents including Claude Code, Cursor, Codex, Zed, Windsurf, Gemini, Copilot, and OpenCode.
- •PMB automatically recalls relevant memory before agent responses and records work after interactions without requiring explicit memory-tool usage on the read path.
- •The retrieval system is described as a hybrid stack using BM25, dense vectors, an entity graph, optional reranking, and Reciprocal-Rank-Fusion, with a stated 94.5% recall@10.
- •The product includes visual interfaces such as a graph-based Map and a git-graph-style Timeline for inspecting facts, decisions, lessons, entities, and project history.