hypothesis-tree

hypothesis-tree is a skill for Claude Code, Codex from fzfclee/consulting-skills. It costs 49 tokens per session (719 once invoked), scanned A, original, Apache-2.0.

A method for testing competing explanations for an observed problem or result. Each explanation is turned into a branch that can be checked against evidence, including evidence that could prove it wrong.

In plain words
What is it for?
Use it to investigate problems, compare possible causes, organize evidence, and guide decisions when several explanations are possible.
Why use it?
It keeps analysis focused on finding the most likely cause instead of describing every aspect of a situation. It also reduces the risk of accepting an attractive explanation without testing it.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it to investigate problems, compare possible causes, organize evidence, and guide decisions when several explanations are possible.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/fzfclee/consulting-skills/hypothesis-tree
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 fzfclee/consulting-skills --skill hypothesis-tree
Clone the repo
git clone --depth 1 https://github.com/fzfclee/consulting-skills

Made for: Claude Code, Codex.

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 hypothesis-tree

README.md
[![agentmods](https://agentmods.dev/badge/skills/fzfclee/consulting-skills/hypothesis-tree/github.svg)](https://agentmods.dev/skills/fzfclee/consulting-skills/hypothesis-tree)
Your own site
<a href="https://agentmods.dev/skills/fzfclee/consulting-skills/hypothesis-tree"><img src="https://agentmods.dev/badge/skills/fzfclee/consulting-skills/hypothesis-tree/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 hypothesis-tree

Your own site · 80×15
<a href="https://agentmods.dev/skills/fzfclee/consulting-skills/hypothesis-tree"><img src="https://agentmods.dev/badge/skills/fzfclee/consulting-skills/hypothesis-tree.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 49 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 719 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 $0.00049 $0.00719
Opus 5 $0.00024 $0.00360
Sonnet 5 $0.00010 $0.00144
Haiku 4.5 $0.00005 $0.00072

Measured 9d ago against content hash 5aeb26631be8, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-09, from the pricing page.

Security

Grade A, and why

hypothesis-tree 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 9d 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/hypothesis-tree/SKILL.md · 86 lines

How it starts

The opening of the file, as written. The whole thing — 86 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Hypothesis Tree

Use this skill to run Hypothesis Tree as a practical consulting method, not as a generic framework explanation.

Method Notes

  • Each branch must be testable.
  • Define disconfirmation evidence, not only supporting evidence.

Required Inputs

Collect or infer these inputs before execution:

  • core question
  • candidate explanations
  • available evidence
  • decision deadline

If an input is missing, do not block automatically. Mark it as missing, state the assumption used, and add a validation action.

When Not To Use

Do not use without a decision question and branches that can be tested with evidence. For open-ended exploration before hypotheses are available, use a mind map or affinity diagram.

Adjacent Methods

  • issue-tree: decompose the question into analysis branches before proposing explanations.
  • abductive-reasoning: rank the best current explanation from incomplete evidence.

Step-by-Step Execution

Step Required input How to execute Output
Frame hypothesis area Problem, observed outcome, decision need. State what explanation or bet needs testing. Hypothesis frame.
Create competing hypotheses Known facts and plausible causes. List alternative explanations or strategic bets. Top-level hypotheses.
Break into sub-hypotheses Top-level hypotheses. Make each branch testable and specific. Hypothesis tree.
Define tests Hypothesis tree and available evidence. Specify supporting evidence and disconfirming evidence for each leaf. Test plan.
Prioritize tests Test plan, impact, speed, uncertainty. Choose fastest tests that could change the decision. Testing sequence.

Output Template

### 1. Decision Question
Question:
Scope:
Current evidence:
Decision deadline:

### 2. Competing Hypotheses
| Hypothesis | Sub-hypotheses | Evidence for | Evidence against | Confidence |
|---|---|---|---|---|
|  |  |  |  |  |

### 3. Disconfirming Tests
| Hypothesis | Cheapest decisive test | Owner | Timing | Threshold |
|---|---|---|---|---|
|  |  |  |  |  |

### 4. Priority
First hypothesis to test:
Why:
Decision unlocked:

### Evidence And Next Decision
- Confirmed facts:
- Assumptions:
- Missing evidence:
- Next action, owner, and timing:
- Expected signal and decision threshold:

Read the full file on GitHub · 86 lines

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. 9d ago First seen · 86 lines · 49 tokens per session scan A 5aeb26631be8

Subscribe to this mod's changes

hypothesis-tree is a skill published in the GitHub repository fzfclee/consulting-skills (4 stars, last pushed 21d ago), licensed Apache-2.0. It adds 49 tokens to every session and 719 once invoked, about $0.0002 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.