architect

1# Architect
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3On Codex, read the [platform mapping](../poteto-mode/references/codex-tools.md), including its per-skill notes, before following this skill.
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5On GitHub Copilot, read the [platform mapping](../poteto-mode/references/copilot-tools.md), including its per-skill notes, before following this skill.
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7On Muse, read the [platform mapping](../poteto-mode/references/muse-tools.md), including its per-skill notes, before following this skill.
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9On Antigravity, read the [platform mapping](../poteto-mode/references/agy-tools.md), including its per-skill notes, before following this skill.
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11Sketch types, function signatures, class shapes, and module boundaries with `not implemented` bodies and pseudocode. Synthesize across multiple model perspectives, then fill in code against the chosen sketch.
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13## Start
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15Open a todolist with one entry per phase before starting.
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171. Ground
182. Sketch
193. Agree
204. Implement
215. Scrap
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23## Phase A: Ground the problem
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25Build a real mental model of every system the new code touches. Run the **how** skill over the relevant subsystems. Naming a file isn't grounding. Produce the architectural explanation `how` prescribes. If the design redefines ownership or layering, also run the **why** skill on the existing shape so the rationale becomes a constraint, not a guess.
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27Skip Phase A only when the work is genuinely greenfield with no surrounding system to integrate.
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29## Phase B: Sketch
30…