Harness Engineering

Designing the environment around the agent: tools, permissions, feedback loops.

The signal a harness gives an agent about the result of its actions (success, error, output) so it can adjust its next step.

e.g. Returning a compiler error so the agent can fix its own code.

Designing the tools, permissions, and feedback loops around an agent so it can act effectively and safely in its environment.

e.g. Deciding which shell commands an agent is allowed to run.

Logging and tracing an agent's decisions, tool calls, and outputs so developers can debug and improve its behavior.

e.g. A trace viewer showing every tool call an agent made during a task.

The rules governing which actions an agent may take autonomously versus which require human approval.

e.g. Auto-approving file reads but requiring confirmation before a git push.

Running an agent's actions in an isolated environment so mistakes or malicious commands can't affect production systems.

e.g. Executing generated code inside a disposable container.

The schema (name, description, parameters) that tells a model what a tool does and how to call it correctly.

e.g. A well-written description prevents a model from misusing a delete_file tool.