Claude Code Thinking Skills is a catalogue of 28 portable skills that give coding agents structured procedures for reasoning about decisions, diagnosis, risk, strategy, and related problems. It is intended for Claude Code, GitHub Copilot, Codex, Cursor, and other tools that support Agent Skills.
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.
npx skills add tjboudreaux/cc-thinking-skills --skill thinking-opportunity-costgit clone --depth 1 https://github.com/tjboudreaux/cc-thinking-skillsWrote 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.
[](https://agentmods.dev/skills/tjboudreaux/cc-thinking-skills/thinking-opportunity-cost)<a href="https://agentmods.dev/skills/tjboudreaux/cc-thinking-skills/thinking-opportunity-cost"><img src="https://agentmods.dev/badge/skills/tjboudreaux/cc-thinking-skills/thinking-opportunity-cost/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.
<a href="https://agentmods.dev/skills/tjboudreaux/cc-thinking-skills/thinking-opportunity-cost"><img src="https://agentmods.dev/badge/skills/tjboudreaux/cc-thinking-skills/thinking-opportunity-cost.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- Socket pass
- Snyk pass
- NVIDIA SkillSpector pass
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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00036 | $0.00845 |
| Opus 5 | $0.00018 | $0.00423 |
| Sonnet 5 | $0.00007 | $0.00169 |
| Haiku 4.5 | $0.00004 | $0.00085 |
Grade A, and why
thinking-opportunity-cost 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 13d 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.
How it starts
The opening of the file, as written. The whole thing — 56 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Opportunity Cost
Core rule: every commitment displaces its best alternative. Report both that forgone value and the net value delta; decide on the delta, not the chosen path alone.
When to Use
- Allocating scarce time, headcount, budget, or attention across competing options
- Feature prioritization, build-vs-buy, tech-debt vs product work
- Saying yes to a large commitment that displaces other work
- Comparing a bold path against polishing the status quo when windows may close
When NOT to Use
- Trivial or cheaply reversible choices where analysis costs more than the resource
- No real alternative use (resource is idle, earmarked, or non-fungible)
- Mandatory work (compliance, security fix, hard dependency) with no optional alternative
- Inventing speculative alternatives only to look rigorous when the next-best is clearly worse
Procedure
- State the commitment. Name the choice, the scarce resource units (eng-weeks, dollars, calendar), and the decision horizon.
- List real alternatives, including do-nothing. At least: proposed option, next-best productive use of the same resources, and status quo / wait. Drop fantasy options with no owner or feasibility.
- Value each path. For each alternative, estimate direct value, strategic value, risk, and time-to-value in the same units. Prefer rough comparable magnitudes over fake precision.
- Compute best forgone value and value delta. Identify the single best non-chosen alternative (may be do-nothing).
best_forgone_value= its estimated value.value_delta=chosen_value − best_forgone_value(same units). True cost of choosing = direct cost of the choice +best_forgone_value. Prefer the option with the superior (positive) value delta after risk; a large positive chosen value is not enough if the forgone alternative is larger. - Future tradeoff / permanent forgone options. For serious alternatives (including the bold path): mark temporary recoverable costs vs permanent losses (window closes, lock-in, no re-entry). Prefer avoiding the greater permanent loss when acting downside is recoverable and non-catastrophic—even if near-term value_delta is slightly negative. Do not invent permanence for speculative upside without evidence.
- Strongest countercase and decide. Steel the case that the best alternative or its value is misidentified (sunk-cost anchoring, status-quo undervalued, or a "free" option that still burns time). Recompute
value_deltaunder that challenge. Then choose: proceed if delta stays favorable (or permanent-loss rule applies), else switch, wait, or split. Stop when ranking is stable.
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.
- 13d ago First seen · 56 lines · 36 tokens per session scan A d6a83af92038
thinking-opportunity-cost is a skill published in the GitHub repository tjboudreaux/cc-thinking-skills (1,306 stars, last pushed 1mo ago), licensed MIT. It adds 36 tokens to every session and 845 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 2026-08-30.
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