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Coding Agents
Tier 4
Plandex
Summary
A terminal agent built for large, multi-file tasks: plans changes across steps, accumulates them in a protected sandbox separate from the working tree, and applies them only when approved.
Key Takeaways
- Accumulate changes in a staging sandbox; apply atomically on approval
- Long tasks need plans that survive across model calls
Reliability Note
Official repository of an actively maintained project.
Flows informed by this source
2Agent Architecture
From CLI Harness to Product
Grow a working agent loop into a product: sessions, config, resumability, and the packaging polish the successful terminal agents share.
01Implement persistent sessions
02Build true resume
03Layer the configuration system
+2 more steps to Done
Best forbuilders who have shipped a basic app before
5 steps90-150 minutesIntermediate
Agent Architecture
Add a Plan/Todo System to Your Agent
Give your agent the planning discipline of the leading harnesses: an explicit, model-visible todo list that survives long tasks.
01Design the todo data model and tool
02Render the plan into context every turn
03Enforce plan-first and completion gates
+1 more steps to Done
Best forbuilders who have shipped a basic app before
4 steps60-90 minutesIntermediate