# Harness engineering

_Reliability around the model_

- Focus: Evals & guardrails
- Result: Output you can gate on

Skills, guardrails, evals and cost control around your coding agents, so the whole team ships like your best engineer. Built for Pilot first.

A coding agent with no harness does what any model does by default: copies whatever pattern is closest in the repo, skips the tests nobody asked for, and burns tokens on the wrong files. The harness is what turns that into a colleague.

## What you're aiming for

- Every engineer's agent producing the same architecture, not five styles.
- A junior with an agent shipping at the level of your senior.
- Knowing what a task cost before the invoice.
- One playbook the whole team uses instead of private prompt folders.

## The harness we build

The harness is everything between the model and your codebase.

- Skills and playbooks: your conventions encoded so the agent reads them before it writes.
- Guardrails: what it can run, what it can touch, what needs a human.
- Evals: a suite that tells you when a model update made things worse.
- Observability: every step logged, every failure traceable.
- Cost control: budgets per task, and the numbers to back them.

## What we've shipped this way

Pilot's harness is the one we ship to ourselves: quality gates, autopilot rules, retry ladders and a cost ledger per issue. Navigator, our open-source Claude Code plugin, is the playbook layer of that harness and is on GitHub.

## How to start

We start from your repo and your team's actual agent sessions, not from a template. Scope and price are fixed before we build.

From you: a repo, two or three engineers who already use an agent, and their real transcripts.

From us: the harness, the evals, a playbook your team owns, and a handover.


---

Hire us: hello@quantflow.studio · https://quantflow.studio/#contact