Why

A skill named in bold or in backticks, or run as /<name>, is the file ../<name>/SKILL.md beside this skill's directory, and a principle named without its prefix is ../principle-<name>/SKILL.md. Read the file and follow it. Most pstack skills are user-only, so your skill tool cannot load them. Every delegate_task call follows the defaults in the Subagents section of ../poteto-mode/SKILL.md.

Investigate the motivation and intent behind code. The companion how skill answers what the code does and how it works. why answers what forces led to its shape.

Each spawn below is a delegate_task child with mode: "async", and names a role line in ~/.config/pstack/pstack-models.md. An entry <providerInstanceId>/<model> (<effort>) becomes target: {"providerInstanceId": ..., "model": ..., "options": {"<effort option id>": "<effort>"}}, with the effort option id orchestrator_capabilities lists for that model. Omit target when the value is auto or inherit-parent, or when the file or the line is missing, so the child runs on the parent thread's model. With no file, say so and suggest /setup-pstack. If delegate_task rejects an entry, use the closest model of the same provider that orchestrator_capabilities lists, and say so. Pick each subagent's reasoning level and fast or standard speed for the job, per the Subagents section of the poteto-mode skill. The child gets only its brief, so paste each reference file it gets into the brief, or give its absolute path. End the turn after spawning and let the completion notifications wake you.

Every spawn keeps the runtime mode inherited. Do not pass a weaker mode. It strips MCP access, which disables the MCP-backed investigators and the synthesizer's citation spot-checks. No spawn should write anything, so each brief says read-only: inspect only, no writes, no git commands that change state.

Operating Posture

Operate as a careful, cautious, and precise investigator. Be honest about what you know vs what you're inferring. Read references/epistemics.md for the full confidence framework and phrasing guide. The synthesizer must follow it.

Step 1. Understand the Target and the Question

The target is usually a chunk of code, a pattern, a feature, or a named design decision. The question is usually a design rationale, a tradeoff, a motivating edge case, an external constraint, dead code, or a broad history sweep.

If the target is vague ("why do we do it this way?" with no clear referent), make your best guess from conversation context (open files, recent edits, what was just discussed). State your interpretation briefly so the user can redirect if you're off, then proceed.