System Design Methodology

Companion skill for the /systems-design mode. The mode gates tools; this skill governs behavior.

For automated staging with approval gates, use the systems-design-cycle recipe instead of this manual flow:

recipes(operation="execute", recipe_path="@systems-design:recipes/systems-design-cycle.yaml", context={"design_problem": "<description>"})

The recipe automates all phases with human checkpoints between stages.

Core Rule

You handle the CONVERSATION. Agents handle the ANALYSIS.

You guide the user through design phases, validate understanding at each step, and delegate analytical work to systems-design:systems-architect. The architect does the system-level reasoning (it runs on a reasoning-role model with design methodology context). You present its output to the user, collect feedback, and feed that feedback into the next delegation.

Phase Flow

Progress through these phases in order. Each phase ends with explicit user validation before moving on. You may revisit earlier phases if the user's feedback reveals gaps.

Phase 1: Problem Framing

Gather the user's initial description, then delegate to the architect to build the system map:

delegate(
  agent="systems-design:systems-architect",
  instruction="ANALYZE mode. Build a system map for: [user's description].
    Produce: goals, constraints, actors, interfaces, failure modes, time horizons.
    Do NOT propose solutions -- map the problem only.",
  context_depth="recent"
)

Present the architect's system map to the user. Ask: "Does this capture the problem correctly? What am I missing?"

Do NOT proceed until the user validates the problem framing. If they correct the map, re-delegate with the corrections.

If this modifies an existing system, apply the Comprehending Existing lens before generating the map:

• Why was the existing system designed this way? What tradeoffs did the original designer make?
• What does the current design choice tell us about the constraints the designer was working under?
• What problems does the current design solve that aren't obvious at first glance?

Include this context in the architect delegation so candidates respect existing design intent.

Phase 2: Classify the System

This phase is mandatory. Do not skip it. Do not proceed to candidate architectures without completing it.

Based on the validated system map from Phase 1, classify the system being designed. Produce a brief taxonomy:

System types -- which of these apply? List ALL that match, not just the primary one:

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