arnesto: Skill for Claude Code

.agents/skills/thinking-in-bets/SKILL.md

thinking-in-bets is a skill for Claude Code, Codex from saski/arnesto. It costs 76 tokens per session (492 once invoked), scanned A, a copy of thinking-in-bets, Unlicense.

A decision-making framework for situations where the outcome is affected by uncertainty and luck.

In plain words
What is it for?
Use it to state assumptions, make probabilistic decisions, review past choices, and reduce outcome-based bias.
Why use it?
It helps you judge how well a decision was made using the information available at the time, instead of judging it only by the result.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: installed under .agents/ (shared by several agents).

This is saski/arnesto's own configuration. It tells Claude Code and Codex how to work on arnesto itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything arnesto configures →

Reuse

Borrowing it

Nothing to install: this file belongs to saski/arnesto. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/saski/arnesto/main/.agents/skills/thinking-in-bets/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/saski/arnesto

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 thinking-in-bets

README.md
[![agentmods](https://agentmods.dev/badge/skills/saski/arnesto/thinking-in-bets.svg)](https://agentmods.dev/skills/saski/arnesto/thinking-in-bets)
Your own site
<a href="https://agentmods.dev/skills/saski/arnesto/thinking-in-bets"><img src="https://agentmods.dev/badge/skills/saski/arnesto/thinking-in-bets.svg" alt="Measured on agentmods" height="20"></a>
Per session 76 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 492 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 100% copy Near-identical to another mod 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 $0.00076 $0.00492
Opus 5 $0.00038 $0.00246
Sonnet 5 $0.00015 $0.00098
Haiku 4.5 $0.00008 $0.00049

Measured 3d ago against content hash a7b6e515afa1, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

thinking-in-bets 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 3d 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.

Origin

This is a copy

100% identical to thinking-in-bets — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

.agents/skills/thinking-in-bets/SKILL.md · 54 lines

What it actually says

Domain Context

This skill implements a proven product management framework. The approach combines best practices from industry leaders and is designed for practical application in day-to-day PM work.

Input Requirements

  • Context about your product, feature, or problem
  • Relevant data, research, or constraints (recommended but optional)
  • Clear articulation of what you're trying to achieve

Thinking in Bets

What It Is

Thinking in Bets is a framework for improving decision quality by separating decisions from outcomes. The core insight: a good decision can have a bad outcome, and a bad decision can have a good outcome—luck is always involved.

Most people judge decisions by their outcomes (called "resulting"). This is backwards. You can only control the quality of your decision, not the outcome.

The key shifts:

  • Move from "Was I right?" to "Was my thinking process good?"
  • Move from "What happened?" to "What did I know at the time?"
  • Move from implicit assumptions to explicit, testable beliefs

When to Use It

Use Thinking in Bets when you need to:

  • Evaluate past decisions without outcome bias clouding judgment
  • Make decisions under uncertainty where luck will influence results
  • Improve team decision-making in meetings and planning
  • Set up pre-mortems and kill criteria for projects
  • Shorten feedback loops on decisions with delayed outcomes
  • Reduce cognitive biases like overconfidence, hindsight bias, and sunk cost
  • Run better meetings that surface true opinions, not groupthink

When Not to Use It

  • The decision is trivial with low stakes
  • You have perfect information (rare)
  • You're looking for permission to take a risk you've already decided on

Resources

Books:

  • Thinking in Bets by Annie Duke
  • Quit: The Power of Knowing When to Walk Away by Annie Duke
  • Thinking, Fast and Slow by Daniel Kahneman
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. 3d ago First seen · 54 lines · 76 tokens per session scan A a7b6e515afa1

Subscribe to this mod's changes

thinking-in-bets is a skill published in the GitHub repository saski/arnesto (5 stars, last pushed today), licensed Unlicense. It adds 76 tokens to every session and 492 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to thinking-in-bets, differing in 0 lines, and is treated as a copy.