Project ideas from Hacker News discussions.

Agents don't need memory, they need documentation

📝 Discussion Summary (Click to expand)

1. Memory vs. Documentation – Many argue that relying on opaque “memory” leads to token bloat and stale information, while explicit documentation externalizes the program’s mental model.

“having built something similar for tracking 'memory' and items at home, it can quickly consume your tokens when dealing with both reading and updating, keeping stale info relevant etc.. when the amount of data starts to grow.” — alienbaby

2. Principles & Mental Models – Instead of raw memory, versioned principles or decision records give agents reusable frameworks to make consistent decisions without constant prompting.

“Something I started doing recently was writing out principles instead of memories. Essentially patterns the agents need to always think in. I also implemented a versioning system to the principles that need to be quoted in any comments which are there in the code.” — bushido

3. Deterministic Tooling/Hooks – Hooks, lint rules, and custom skills enforce correct tool usage (e.g., preferring jq over ad‑hoc Python scripts) by providing immediate, predictable feedback.

“Hooks should (in my opinion) be deterministic… I’m going to write a hook which triggers on those and fails the turn telling it to use jq instead.” — jon‑wood

4. Testing/TDD as Context – A tight test‑driven loop supplies continuous verification and acts as living documentation, guiding agents on what the code should do.

“I’ve been trying to nudge agents (both Claude and GPT) into a red/green/refactor TDD loop…” — jon‑wood


🚀 Project Ideas

Versioned Principle Engine

Summary

  • A CLI and library that lets teams define, version, and share coding principles as lightweight YAML/JSON files, automatically injecting the current principle versions into agent prompts via specially formatted code comments.
  • Solves the problem of agents drifting from team mental models and needing constant re‑explanation, reducing token‑heavy context and manual documentation.

Details

Key Value
Target Audience Teams using AI coding agents (Claude Code, OpenCode, Copilot) who want consistent design guidance
Core Feature Versioned principle definitions with automatic comment injection and re‑validation hook that triggers when a principle version bumps
Tech Stack Rust (file watcher), TypeScript SDK for agent integration, JSONSchema for principle schema, GitHub Actions for CI
Difficulty Medium
Monetization Revenue-ready: Subscription per team ($10/mo) + enterprise tier

Notes

  • Bushido’s approach shows agents follow versioned principles when they are cited in comments (// PDD-3@v1), and HN commenters noted “I’ve had surprisingly good adherence from agents on this technique.”
  • Enables teams to evolve mental models without agents generating outdated or made‑up rules, addressing the concern about agents writing their own ADRs.

Context Pruning & Token Budget Manager

Summary

  • A hook‑based middleware for AI coding harnesses that extracts semantic statements from each prompt/response, builds a lightweight Whybase proposition tree, and automatically prunes stale or subsumed propositions to keep the token budget under a user‑defined limit.
  • Directly tackles the token‑explosion problem described by alienbaby and the need for dynamic context pruning mentioned by cyanydeez.

Details

Key Value
Target Audience Solo developers and small teams running local LLMs (Qwen, Llama) who hit token limits quickly
Core Feature Real‑time statement extraction, proposition tree storage (SQLite), and pruning based on recency and logical subsumption
Tech Stack Python (LLM hook), spaCy/fast‑text for statement parsing, SQLite, optional WASM for edge
Difficulty High
Monetization Hobby (open‑source) – could later offer hosted version

Notes

  • espeed’s Whybase tree and alienbaby’s token‑cost concerns show a clear demand; HN users said “keeping a good solid reference … works wonders” but token cost grows with data.
  • Provides a measurable way to bound context, useful for discussion on optimal pruning strategies and for reproducible agent sessions.

Agent Memory Invalidator via File Hash

Summary

  • A lightweight daemon that attaches memory snippets (markdown or JSON) to source files via extended attributes or a side‑car .memory file, and automatically invalidates/removes them when the file’s content hash changes, with optional cross‑file dependency tracking.
  • Addresses the frustration of stale memory accumulating (alienbaby, nextaccountic) and the overly eager dropping seen in Copilot.

Details

Key Value
Target Audience Developers using AI agents that rely on per‑file memory or note‑taking (e.g., Claude Code memos, agent‑skills)
Core Feature Hash‑based invalidation with configurable grace period and dependency graph to prevent premature drops
Tech Stack Go (cross‑platform daemon), SQLite for hash store, optional libgit2 for tracking changes
Difficulty Medium
Monetization Revenue-ready: SaaS free tier, paid for private repositories ($5/user/mo)

Notes

  • nextaccountic asked about dropping outdated propositions; Github Copilot’s file‑hash approach was mentioned as a starting point.
  • Commenters like espeed noted the need for a mechanism to drop older, subsumed propositions; this tool gives explicit control, reducing memory bloat and token waste.

Deterministic Tool Enforcement Hook Framework

Summary

  • A pluggable hook system for AI coding agents that intercepts tool calls (e.g., shell, editor) and enforces a whitelist of approved utilities (jq, ffmpeg, etc.), providing deterministic feedback and auto‑suggesting corrections when agents attempt ad‑hoc scripts.
  • Directly solves the widespread issue of agents generating unnecessary Python/Javascript one‑liners instead of using existing CLI tools, as highlighted by spike021, locknitpicker, and many others.

Details

Key Value
Target Audience Teams employing AI coding assistants who want to reduce token waste and improve reliability
Core Feature Hook runtime (written in Rust) that agents invoke via MCP or skill, with rule definitions in YAML; includes logging and audit dashboard
Tech Stack Rust core, Node.js/YAML for rule editor, optional Web UI (React) for monitoring
Difficulty Medium
Monetization Revenue-ready: Per‑seat licensing ($8/mo) with free open‑source core

Notes

  • locknitpicker observed that agents ignore skills and keep generating ad‑hoc python scripts; spike021 noted the cost of burning tokens.
  • HN users expressed desire for deterministic feedback (“I’ve found that most of LLM generated docs are diluted…”); this framework gives explicit, enforceable guidance, encouraging discussion on best tool usage and reducing AI‑generated noise.

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