Designing with Jax

Jax is fastest when you give it enough context to do the work without ping-pong. Here are the patterns we recommend.

State the objective, the scope, and what matters

A good prompt has three pieces:

• Objective — what you want produced (a network, a route, a layout).
• Scope — where it should apply (a polygon, a layer subset, a time window).
• Constraints that matter to you — anything beyond what the agent skill already

enforces.

Don’t restate the skill. Jax already knows it. If your FTTH skill says splitters must be 1:32 max, you don’t need to say so.

Reference what’s already in your project

Pointing at things that exist beats describing them in prose:

Use the polygon I just drew as the scope. Snap routes to the road network already loaded. Avoid existing duct.

Jax navigates your project on its own — you don’t need to spell out where things are.

Iterate in small bites

You can ask for the whole world in one prompt — Jax will do its best — but iteration is cheaper:

1. “Plan the cabinet locations.”
2. (Inspect on the Globe.) “Move cabinet 7 closer to the existing handhole.”
3. “Now route distribution from those cabinets.”
4. “Validate against the constraints in the skill and list any violations.”

Each step builds on the last. You can roll back at any time.

Use “why” aggressively

Jax is built to explain itself. After any non-trivial action:

• “Why did you put cabinet 4 there?”
• “Walk me through your reasoning — what was the cost driver?”
• “Which constraints were binding?”

Use this both to learn the system and to catch silent mistakes.

When to hand it a skeleton

If you have prior work or a partial design, give it to Jax instead of starting fresh. Import what you have, point at it, and say “refine, don’t replace.” This is dramatically faster than describing what you already have.

When Jax pushes back

Sometimes Jax will tell you a request is infeasible — the polygon has no road access; the constraint set is over-specified; the math couldn’t converge. Take that seriously. Loosen a constraint, narrow the scope, or ask Jax for a counter-proposal.