Custom Harnesses are the Real Key for Agents
hwchase17 · x · 2026-07-14
The author argues that to build a successful agent for spreadsheet tasks, the key is to focus on the harness, not just the model itself.
Key conclusions include:
- Shortcut's core competitive edge is its agentic performance on spreadsheet tasks
- To beat the big model providers, building a custom harness is mandatory
- The post includes an article on how to build a harness, quoting discussions on why "startups still hold a structural advantage"
Related event: Agent Differentiation Shifts From Models to Harness Design(8 posts)→
More from coding & agent
- 10,000 Agents, 88 Hours to Solve CS's Hardest Problems? Skeptic Predicts the Inevitable Backlash — IgorCarron · 2026-09-12
- Devin Fusion debuts on Coding Agent Index, keeps frontier performance at lower cost — daniel_mac8 · 2026-09-12
- Stress-Testing an AI Gateway With 100 Concurrent Agents: All HTTP 200, Continuity Collapsed — its_vayishu · 2026-09-12
- Blender MCP hands-on: impressive engineering, but outputs need a full remodel — Intelligent_Prize532 · 2026-09-12
- Managing an army of Claude-built agents: memory, tools, and harnesses — Trokkan · 2026-09-12
- DeepSeek 4.1 Flash wired into Claude Code: open-source model runs agent workflows — jasonkneen · 2026-09-12