Harness engineering
Harness engineering.
Agent equals model plus harness. The harness is the half you can actually change.
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sha256 698955a0187bc039f4c74f5d05a9f10fbb27376a45788a0a241d1326b73873c7
$curl -fsSL https://lucidtrain.com/install.sh | sh
- What Is a Coding Harness?Everything in the agent that is not the model. The part you can actually change.
- Harness Engineering vs Context EngineeringOne is a component of the other, and confusing them is why teams optimise the wrong thing.
- Coding Agent vs HarnessAgent equals model plus harness. The harness is the half you control.
- Is Claude Code a Harness?Both, and the confusion is in the question rather than the answer.
- Is GitHub Copilot a Harness?Two products under one name, and only one of them is a harness.
- Choosing a Coding HarnessThe honest answer is that it depends on constraints, and here are the constraints that actually decide it.
- Coding Harness for Local LLMsThree requirements, and most harnesses fail at least one of them.
- Harness Design PatternsThree labs, three vocabularies, one shared concept between them. Here is the mapping.
- Context Management in a Coding HarnessEvery harness works on a small task. Context management is what separates them at the limit.
- Verification in a Coding HarnessThe agent cannot mark its own homework, and there is now published evidence rather than just a suspicion.
Elsewhere
- System Design TemplatesEach template is a real diagram produced by the same layout engine the app runs, not a picture of one.
- MCP and Architecture DiagramsYour agent supplies the structure. A constraint solver decides where everything goes.
- Generate a Diagram from Your CodeEvery source below lists the exact files it reads and the constructs it maps to diagram nodes.
- AI Diagram GeneratorsThe agent emits a semantic graph and ELK computes the layout, so overlapping boxes are structurally impossible.
- Compare Lucid TrainEvery page says what the other tool is better at. If that section were empty the comparison would not be worth reading.
- Convert Code and DiagramsEvery conversion page states what survives the round trip and what does not.
- Use CasesEach page includes who it is not for, which is usually the more useful half.
- Beyond DiagramsDiagrams are the front door. These are the rooms behind it.