prime-expand

prime-expand is a skill for Claude Code from allemaar/open-skills. It costs 121 tokens per session (1,595 once invoked), scanned A, original, Apache-2.0.

A delegated helper that turns a vague information gap into a specific question and possible sources to investigate. A delegated helper is a separate worker used to keep the main conversation focused.

In plain words
What is it for?
Use it when you need to clarify what must be learned and identify credible source candidates for the next research step.
Why use it?
It makes an unclear request more precise before research begins, without exposing the helper’s intermediate reasoning.

Skill for Claude Code

Written for Claude Code: shipped in a Claude Code plugin. Also seen: mentions subagents.

Part of the open-skills plugin — 70 skills shipped together

Good fit Use it when you need to clarify what must be learned and identify credible source candidates for the next research step.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/allemaar/open-skills/prime-expand
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add allemaar/open-skills --skill prime-expand
Clone the repo
git clone --depth 1 https://github.com/allemaar/open-skills

Made for: Claude Code.

Or install open-skills, the plugin that ships this one along with the rest of its 70 skills.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for prime-expand

README.md
[![agentmods](https://agentmods.dev/badge/skills/allemaar/open-skills/prime-expand/github.svg)](https://agentmods.dev/skills/allemaar/open-skills/prime-expand)
Your own site
<a href="https://agentmods.dev/skills/allemaar/open-skills/prime-expand"><img src="https://agentmods.dev/badge/skills/allemaar/open-skills/prime-expand/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for prime-expand

Your own site · 80×15
<a href="https://agentmods.dev/skills/allemaar/open-skills/prime-expand"><img src="https://agentmods.dev/badge/skills/allemaar/open-skills/prime-expand.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 121 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,595 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector pass 7 Sept 2026
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00121 $0.01595
Opus 5 $0.00060 $0.00797
Sonnet 5 $0.00024 $0.00319
Haiku 4.5 $0.00012 $0.00160

Measured 12d ago against content hash 737d07c088b6, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-12, from the pricing page.

Security

Grade A, and why

prime-expand scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 12d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skills/prime-expand/SKILL.md · 121 lines

How it starts

The opening of the file, as written. The whole thing — 121 lines — stays where its author put it; the contents beside it link to each section on GitHub.

/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.

Read the full file on GitHub · 121 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 12d ago First seen · 121 lines · 121 tokens per session scan A 737d07c088b6

Subscribe to this mod's changes

prime-expand is a skill published in the GitHub repository allemaar/open-skills (14 stars, last pushed 2d ago), licensed Apache-2.0. It adds 121 tokens to every session and 1,595 once invoked, about $0.0006 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.