Prime Expand

/prime-expand

Expand a vague gap statement into a concrete priming target — sharp question(s) + validated source candidates — via a delegated sub-agent, so the expansion reasoning never enters the caller's context. The caller sees only the proposed pair and confirms, edits, or refuses.

Structured execution spec: protocol.yon. Read it for the canonical rules and step sequence; this file is explanation. The two must stay in sync — if you edit one, update the other and refresh the @STAMP date.

Caller Options. Before executing, run the Caller Options protocol (caller-options/SKILL.md): triage this invocation for material optionality across the venues and modes declared in front-matter; if one path clearly dominates, proceed silently; otherwise surface the options to the caller.

Family invariant — /prime-* skills delegate. Every /prime-* skill uses sub-agents so the caller's context stays clean. /prime-expand is the lightest member: one sub-agent, one turn, no deep reading.

Boundary

Use /prime-expand to turn a fuzzy "I should know more about X" into a sharp {question, sources[]} pair ready to feed downstream priming. Do not use it for actual investigation — that is /prime-fetch (single noisy tool call) or /prime-sweep (large source-surface, parallel sub-agents). Do not use it to gather facts for the user — that is /investigate.

Step 1 — Receive the seed gap

The seed can be a vague statement, a topic, or a worry. Examples:

• "I need to know about auth"
• "what about the cache layer?"
• "expand on yesterday's bug"
• "prime me before I touch the rate-limiter"

If the seed is already a sharp question with named sources, do not run this skill — pass straight to /prime-fetch or /prime-sweep.

Step 2 — Build the context snapshot

Assemble a short snapshot for the sub-agent only. This is the only context-bridge — the sub-agent must not see the caller's full conversation history.

• CWD, project type (language/framework if known).
• Last few files mentioned in this turn.
• The caller's current task or objective if known.

Step 3 — Brief and spawn the sub-agent

Spawn one sub-agent with a fresh context window. The brief contains:

• The seed gap, verbatim.
• The context snapshot from Step 2.
• Light scan permissions: Glob and Read to validate candidate sources exist and look plausible (≤3 files, ≤200 lines each). No deep reading, no Grep, no WebFetch, no Bash.
• Output contract requiring only the proposed pair (or a refusal line).

Step 4 — Sub-agent expands

The sub-agent works in its own window:

1. Parses the seed for likely subject, scope, and missing specifics.
2. Generates 1–3 concrete declarative questions implied by the seed.
3. Proposes ≥1 source candidate per question (file path, URL, doc reference, the conversation above, the search-result dump in turn N).
4. Spot-checks candidates exist (Glob / Read, ≤200 lines each).
5. Discards proposals whose sources don't exist or don't look relevant.

Step 5 — Sub-agent emits the proposed pair

Only the proposed pair returns to the lead. The sub-agent's working/reasoning stays in its own window.

Seed: <original input verbatim>
Expanded:
  Q1: <concrete declarative question>
  Q2: <optional second question if seed implies more than one>
  Sources: [<source 1>, <source 2>, ...]

If the sub-agent cannot produce ≥1 question with ≥1 validated source, it emits:

Seed: <original input verbatim>
Refused: cannot expand — <one-line reason>

Step 6 — Surface for confirm / edit / refuse

The lead presents the proposed pair to the caller (or user) and waits for one of three responses:

• Confirm — emit {question, sources[]} to the caller for direct use, or chain into /prime-fetch / /prime-sweep.
• Edit — caller revises questions or sources; lead re-emits the revised pair.
• Refuse — caller proceeds without priming; skill exits.

Rules

• MUST delegate the expansion work to one sub-agent — the lead never reads sources itself.
• MUST cap the sub-agent's reading to ≤3 candidate-source spot-checks of ≤200 lines each.
• MUST emit only the proposed pair (or a refusal line) to the lead — sub-agent reasoning stays in the sub-agent's window.
• MUST refuse with a one-line reason if the seed cannot be expanded into ≥1 concrete question + ≥1 plausible source.
• MUST NOT let the sub-agent run Grep, WebFetch, Bash, or any tool that produces large output — those belong to /prime-fetch or /prime-sweep.
• MUST NOT allow the sub-agent to spawn further sub-agents (depth-1 cap).
• MUST NOT require proof-of-work citations — this skill produces intent (a question + candidate sources), not factual findings.

Next Steps

• /prime-fetch — if the confirmed pair needs a single noisy data-fetch resolved (Grep, WebFetch, MCP).
• /prime-sweep — if the confirmed pair's sources are large or numerous enough that direct reading would flood the caller's context.

Next skills. On completion, run the Next Skills protocol (next-skills/SKILL.md): surface the next-skills recommendations from front-matter for the caller to pick. Offer only — never auto-invoke.

Self-improvement. On completion, run the Self-Improvement Protocol (self-improve/SKILL.md): if this run surfaced a concrete, blocking-or-recurring weakness in this skill, propose a specific fix for the handler to approve. Conservative — silent otherwise. Never auto-apply.