flush-fidget/PROMPT.md

FLUSH FIDGET — shared agent prompt

Every agent (Claude, Codex, Grok) reads this file first. It is the single source of truth for the project. If something here is wrong, say so in COORDINATION.md; do not quietly work around it.

Goal

Orca Slicer wastes most of the filament on a multi-colour print as purge: one real 4-colour slice used 94 g of purge and prime tower against 19 g for the model itself (392 filament changes). Make that purge land in a flush fidget instead of the tower or a waste bin.

The flush fidget is the print-in-place Flexi Cube at assets/flexi cube.stl. Getting that one file through the whole process is the goal: slice it as the purge target, print it, and have it still flex.

Random colours on the outside are wanted. Purge showing on the exterior in unplanned colours is the desired look, not a defect. Do not hide it inside infill.

Success test

Slice a 4-colour model with the Flexi Cube on the plate as the purge target. Then:

1. The Flushed + Tower totals in Orca's filament table drop substantially against the baseline recorded in tests/baseline.md. Ideal: no prime tower at all.
2. The G-code preview shows purge extruded into the Flexi Cube, with mixed colours on its outer surface.
3. The printed cube still moves. Colour-change purge must not fuse the joints or fill the clearances. This is the hard constraint and the likeliest failure.

The core problem

Purge needed per layer depends on the colour changes on that layer. The cube has a fixed cross-section per layer. They won't match. Layers needing more purge than the cube can take, and layers needing less, both have to be handled. Any design that ignores this will look right in the preview and fail on the printer.

Rules

• Smallest change that works. Do not rewrite the slicer.
• Label every claim VERIFIED (you read the code or ran it) or UNVERIFIED. File paths in this document are guesses until an agent confirms them. A starting guess for the tower code is src/libslic3r/GCode/WipeTower.cpp and WipeTower2.cpp.
• Metric units. No new dependencies without asking Fred.
• Orca Slicer is AGPL-3.0. Keep upstream as a remote. Keep the licence intact.
• Only touch this repo and the Orca fork. Never touch Fred's other workspace files.
• Do not push to main. Do not push anywhere public. Fred decides when anything is published.
• Never print without Fred present.

Team protocol

• Each agent works in its own git worktree on agent/<name>/<task>.
• Claim a task in COORDINATION.md before starting. Two agents never edit the same file at once. Claude merges.
• Write findings to recon/<name>-<topic>.md with file paths and line numbers.
• Put code changes in the Orca fork. Keep the resulting patches in patches/.

Phases

Phase 0 — Baseline (Claude). Build Orca from source on this machine. Record the exact commands and build time in tests/baseline.md. Slice the reference model and record its Flushed and Tower totals there. Nothing proceeds until this works.

Phase 1 — Recon, read-only.

• Codex: trace how the prime tower is generated layer by layer, and where the flush matrix and multiplier feed in.
• Grok: trace the existing "flush into objects' infill / support / this object" feature. Where does purge get routed into an object, and what limits how much it absorbs?
• Claude: inspect assets/flexi cube.stl. Report its volume per layer, joint clearances, and wall thickness. Then set out the options for reconciling purge volume with that cross-section, with effort and risk for each.

STOP after Phase 1. Report to Fred. Write no code until Fred approves one option.

Options to evaluate (do not implement yet)

1. No code: use the existing flush-into-this-object feature with the cube as the target. Say whether it is enough on its own.
2. Extend flush-into-this-object so the chosen object absorbs more, including onto its outer surface.
3. Replace the tower geometry with the cube. Likely hardest.

For each: files touched, effort, and what breaks. Option 2 or 3 must say how the joints stay free.

Reporting

Short and plain. Lead with the answer. If you are unsure, say so and say what would settle it. Fred has ADHD: no walls of text, no unrequested tangents.