Harness engineering
Harness engineering.
Agent equals model plus harness. The harness is the half you can actually change.
$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.
- AI System DesignThe diagram can cause the code, not just describe it.
- Coding Engines Lucid Train Can DriveThe binary is already on your machine and already signed in. Nothing is proxied and no credential passes through us.
- Dependency and Agent Supply Chain AuditYour packages are audited by everyone. The programs your agent launches are audited by almost no one.
- Grafana and Observability in a Coding AgentNothing is exported to us. It reads the Grafana you already run, with your credential, on your machine.
- AI Design Mode for Web PagesRunning on the Claude Code or Codex CLI you already have, with your repository open beside it.
- Software Architecture GlossaryWhat each term means, where it came from, and where it stops being useful.
- Guides to Choosing Architecture ToolsNo winner is declared, because the right answer depends on constraints a web page cannot see.
- Alternatives to Popular Diagramming and Agent ToolsEach page sorts the field by the reason you are leaving, because that is what decides the answer.
- 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.