Harness Tour
The full tour lives in 02-harness-tour.md. This page introduces what you will look for before you start.
The Task
Use Agent Canvas to ask a real code-reading question against agent-canvas:
text
Find every place VITE_BACKEND_HOST and VITE_BACKEND_BASE_URL are read or set
in this project, and write a short note explaining how the dev script picks
the backend.This task is useful because it is narrow, repeatable, and traceable. The agent has to search, read files, connect evidence, and answer without making broad edits.
The Five Parts To Watch
| Harness part | What to inspect | Project that changes it |
|---|---|---|
| Model | Which model answered and how much it cost | P02 |
| Tools | Which tools were available and used | P03 |
| Memory | What the agent knew before searching | P05 |
| Safety | What could run automatically or needed approval | P06 |
| Architecture | Where the work ran and how state persisted | P07 |
The Trace Is The Unit Of Diagnosis
Do not start by judging the final answer. Read the events:
- user message
- assistant planning
- tool call
- tool result
- edit or command
- confirmation
- compaction
- final answer
When a run fails, the trace shows where to look. That is why this course uses OpenHands.