assumptions

assumptions is a skill for Claude Code from kimsanguine/hplan. It costs 66 tokens per session (4,152 once invoked), scanned A, original, MIT.

A workflow for finding and ranking the riskiest assumptions behind an AI-agent idea. It examines value, technical feasibility, reliability, and ethics before implementation begins.

In plain words
What is it for?
Use it to prioritise assumptions, score their risks, and design small validation experiments before building the agent.
Why use it?
It helps teams discover what could make an agent fail in real use, including problems that ordinary technical checks may miss.

Skill for Claude Code

Written for Claude Code: allowed-tools in frontmatter. Also seen: model in frontmatter.

Part of the discover plugin — 6 skills shipped together

Good fit Use it to prioritise assumptions, score their risks, and design small validation experiments before building the agent.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/kimsanguine/hplan/assumptions
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 kimsanguine/hplan --skill assumptions
Clone the repo
git clone --depth 1 https://github.com/kimsanguine/hplan

Made for: Claude Code.

Or install discover, the plugin that ships this one along with the rest of its 6 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 assumptions

README.md
[![agentmods](https://agentmods.dev/badge/skills/kimsanguine/hplan/assumptions.svg)](https://agentmods.dev/skills/kimsanguine/hplan/assumptions)
Your own site
<a href="https://agentmods.dev/skills/kimsanguine/hplan/assumptions"><img src="https://agentmods.dev/badge/skills/kimsanguine/hplan/assumptions.svg" alt="Measured on agentmods" height="20"></a>
Per session 66 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,152 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.
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 $0.00066 $0.04152
Opus 5 $0.00033 $0.02076
Sonnet 5 $0.00013 $0.00830
Haiku 4.5 $0.00007 $0.00415

Measured 7d ago against content hash bbb8f41e19fd, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

assumptions 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 7d 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.

discover/skills/assumptions/SKILL.md · 322 lines

How it starts

The opening of the file, as written. The whole thing — 322 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Core Goal

  • 구현 전에 에이전트의 숨겨진 가정을 발굴하고 리스크를 수치화하여 팀이 무엇을 먼저 검증해야 하는지 명확히 함
  • 4축(Value/Feasibility/Reliability/Ethics) 분석을 통해 기술적 가능성과 실제 운영 가능성의 갭을 조기에 발견
  • 우선순위 점수(위험도 × 검증 난이도)를 기준으로 2일 이내에 실행 가능한 최소 검증 실험을 설계

Trigger Gate

Use This Skill When

  • opp-tree 스킬로 기회를 선택한 후, 구현하기 전에 핵심 가정을 빠르게 검증하고 싶을 때
  • 에이전트 아이디어가 있는데 "정말 작동할 것 같나"에 대한 우려가 있을 때
  • 기술 팀은 구현 가능하다고 하는데 비즈니스 팀이 의심스러워할 때
  • 윤리/안전 위험(예: 잘못된 판단이 고객에게 영향)이 있을 수 있다고 생각할 때

Route to Other Skills When

  • 검증 실험 설계 후 실제로 프롬프트/API를 테스트해야 할 때 → hitl 스킬 (Human-in-the-Loop으로 초기 신뢰도 측정) 또는 본 스킬 --mode build-or-buy
  • 가정 검증 결과 위험도가 매우 높으면 → hitl 스킬로 에스컬레이션 전략 설계
  • 검증 통과 후 에이전트 설계 및 프롬프트/인스트럭션을 작성해야 할 때 → deliver/agent-setup
  • 8축 100점 evidence 루브릭으로 정량 채점이 필요할 때 → evidence-rubric (hplan plugin). V/F/R/E 4축과 상보적.

Boundary Checks

  • 검증의 범위: Assumptions는 가정을 "정의"하고 "우선순위"를 정하는 것이지, 실제로 검증 실험을 끝까지 실행하지는 않음 — 실험 실행은 팀이 직접 담당
  • 이미 검증됨: 기술 스택이 프로덕션에서 이미 검증되었다면(예: 우리 팀이 동일 모델로 다른 에이전트를 성공했다면) 그 가정의 점수는 내려야 함

Agent Assumption Map

에이전트 아이디어에는 수십 개의 숨겨진 가정이 있습니다. 그 중 단 하나만 틀려도 에이전트는 조용히 잘못된 방향으로 실행됩니다.

일반 제품과 다른 점:

  • 일반 제품: 사용자가 결과를 보고 판단 → 오류 발견 즉시 가능
  • 에이전트: 자율 실행 → 오류가 쌓일 때까지 발견 어려움

Agent Assumption Map은 4축 분석으로 핵심 가정을 사전에 발굴합니다.


4축 정의

Axis 1 — Value (가치 가정)

"이 에이전트가 실제로 의미 있는 문제를 해결하는가?"

검토 질문:

  • 자동화 후 실제로 시간/비용/오류가 줄어드는가?
  • 사용자가 에이전트의 결과를 실제로 사용하는가?
  • 에이전트 없이도 충분히 빠르게/잘 할 수 있지 않은가?
  • 자동화로 해결되는 불편함이 진짜 불편함인가, 아니면 낮은 빈도의 사소한 불편인가?

Axis 2 — Feasibility (실현 가능성 가정)

"이 에이전트를 실제로 구현할 수 있는가?"

검토 질문:

  • 필요한 데이터에 접근 가능한가? (API 권한, 인증, 비용)
  • 필요한 툴이 안정적으로 작동하는가?
  • 기술 스택 (모델, 프레임워크) 이 요구사항을 지원하는가?
  • 개발 리소스와 타임라인이 현실적인가?
  • 외부 의존성 (API 변경, 서비스 중단) 리스크는?

Axis 3 — Reliability (신뢰성 가정) ← 에이전트 특화 축

"이 에이전트가 충분히 정확하고 안정적으로 반복 실행 가능한가?"

검토 질문:

  • 정확도 기준은 무엇인가? (90%? 99%? 100%?)
  • 오류 발생 시 자동 감지 및 복구 가능한가?
  • 컨텍스트 길이 / 모델 응답 일관성이 보장되는가?
  • 외부 API 장애 시 에이전트가 어떻게 반응하는가?
  • 장기 실행 시 성능 저하 (컨텍스트 오염, 비용 증가) 없는가?

⚠️ 신뢰성 기준은 용도에 따라 다릅니다. 뉴스 요약 에이전트 (90% 충분) vs 금융 거래 에이전트 (99.9% 이상 필요)

Read the full file on GitHub · 322 lines

Files

What ships with it

5 files 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. 7d ago First seen · 322 lines · 66 tokens per session scan A bbb8f41e19fd

Subscribe to this mod's changes

assumptions is a skill published in the GitHub repository kimsanguine/hplan (2 stars, last pushed 22d ago), licensed MIT. It adds 66 tokens to every session and 4,152 once invoked, about $0.0003 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 2026-08-31.

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