ECC: Agent Harness Performance Optimisation System for Coding Agents

X postTrending GitHub RepositoriesTool

The open-source repository ECC by developer affaan-m has crossed 250,000 GitHub stars. It serves as an agent harness system providing skills, memory, security controls, and engineering workflows for tools like Claude Code, Codex, Opencode, and Cursor.

Key points

  1. Structured workflows: ECC equips coding agents with upfront planning, test verification, fresh-context self-reviews, and memory retention.
  2. Multi-harness support: The framework integrates with platforms including Claude Code, Codex, Cursor, and Opencode.
  3. Installation options: Setup can be handled via the terminal using `npx ecc-universal setup` or natively within Claude Code via `/plugin install ecc@ecc`.
  4. Open source with commercial tier: The core project is MIT-licensed, while a hosted GitHub App (ECC Pro) is offered for private repositories starting at $19 per seat per month.

Why it matters

While raw foundation models can write code, they often lack contextual memory and engineering guardrails. Frameworks like ECC focus on the harness layer to enforce automated testing, review cycles, and reliable tooling around agent interactions.

Analysis

The rapid traction of ECC underscores that developer tooling around AI agents is increasingly defined by the harness rather than the raw model alone. By orchestrating plugins, hooks, memory, and automated verification, ECC addresses common failure modes in autonomous coding tasks across multiple IDE and CLI environments.

Original post

Trending GitHub Repositories

@trending_repos · 7 September 2026

Trending repository of the day 📈 ECC by @affaan The agent harness performance optimization system. Skills, instincts, memory, security, and research-first development for Claude Code, Codex, Opencode, Cur... Last 24h: 1,905 ⭐ Total: 252,299 ⭐️ t.co/Ipk989QzgG

71 likes2 replies139 bookmarks7.4k views

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Selected replies (2)
  • @drpatel @trending_repos Harness layers like skills and memory are becoming the product. The model alone stopped being enough a while ago.
  • @Tanguyvbc @trending_repos ECC calling out the harness layer is spot on. Skills memory and eval loops are the real product.

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