defensibility

defensibility is a skill for Claude Code, Codex from VGrss/Acumen. It costs 43 tokens per session (3,444 once invoked), scanned A, original, Apache-2.0.

An audit of how difficult a product is to copy, including customer switching costs, unique data, network effects, and resilience to AI automation.

In plain words
What is it for?
Use it when reviewing competitive threats, deciding where to invest, assessing product weaknesses, or preparing for fundraising.
Why use it?
It separates durable advantages from ordinary features that competitors can reproduce quickly.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/vgrss/acumen/defensibility
Any agent
npx skills add VGrss/Acumen --skill defensibility
Clone the repo
git clone --depth 1 https://github.com/VGrss/Acumen

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 defensibility

README.md
[![agentmods](https://agentmods.dev/badge/skills/vgrss/acumen/defensibility.svg)](https://agentmods.dev/skills/vgrss/acumen/defensibility)
Your own site
<a href="https://agentmods.dev/skills/vgrss/acumen/defensibility"><img src="https://agentmods.dev/badge/skills/vgrss/acumen/defensibility.svg" alt="Measured on agentmods" height="20"></a>
Per session 43 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,444 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00043 $0.03444
Opus 5 $0.00022 $0.01722
Sonnet 5 $0.00009 $0.00689
Haiku 4.5 $0.00004 $0.00344

Measured 4d ago against content hash d8eec99bfc82, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

defensibility 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 4d 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.

.agents/skills/defensibility/SKILL.md · 309 lines

How it starts

The opening of the file, as written. The whole thing — 309 lines — stays where its author put it; the contents beside it link to each section on GitHub.

MANDATORY PREPARATION

Invoke /product-thinking — it contains the Context Gathering Protocol and the AI Slop Test. Follow the protocol before proceeding.


Mindset

Features can be copied in a quarter. Moats take years to build — if they can be built at all. Defensibility is the audit that tells you where your product is genuinely hard to replicate, where it's vulnerable, and where to concentrate effort to widen the gap.

Most products have less defensibility than their founders think. Brand is not a moat unless switching costs are high. "First mover" is not a moat unless you've converted the head start into something structural. Be honest. The point is not to feel good — it's to know where to build.

In the AI era, a new class of threats has emerged: agents that can automate workflows, commoditize integrations, and make context portable. This audit evaluates both classical moats and AI-era resilience.

Context Pull

  1. Product context. Read .acumen.md — strategy, stage, positioning.
  2. Competitors. Read .acumen/competitors.md — what competitors have, their moats, recent moves.
  3. Features. Read .acumen/features.md — current capabilities and their maturity.
  4. Personas. Read .acumen/personas.md — who depends on us and why they'd stay or leave.
  5. Value chain. Read .acumen/value-chain.md — where the product sits in each persona's workflow. Use this directly for Section 4 (Value Chain Analysis) and Section 5 (Switching Cost Anatomy).

Framing

Before analysis, establish scope. If the user hasn't specified, ask — one question at a time:

Q1 — Object of analysis:

"What exactly are we analyzing? An isolated feature, a product increment (EPIC), a feature set, or the product as a whole?"

Q2 — Perceived threat:

"What's your main concern? Agentic AI erosion? A specific competitor? General market commoditization?"

If the user has already provided this context in the conversation, in an EPIC, or in .acumen.md — extract directly, don't re-ask.

Read the full file on GitHub · 309 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. 4d ago First seen · 309 lines · 43 tokens per session scan A d8eec99bfc82

Subscribe to this mod's changes

defensibility is a skill published in the GitHub repository VGrss/Acumen (11 stars, last pushed 28d ago), licensed Apache-2.0. It adds 43 tokens to every session and 3,444 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.

Related

Other skills, from other repositories

systematic-debugging

Use when encountering any bug, test failure, or unexpected behavior, before proposing fixes.

obra/superpowers · 21 tokens

brainstorming

You MUST use this before any creative work - creating features, building components, adding functionality, or modifying behavior. Explores user intent, requirements and design before implementation.

obra/superpowers · 37 tokens

auto-perf-optimize

Run agent-driven VS Code performance or memory investigations. Use when asked to launch Code OSS, automate a VS Code scenario, run the Chat memory smoke runner, capture renderer heap snapshots, take workflow screenshots, compare run summaries, or drive a repeatable scenario before heap-snapshot analysis.

microsoft/vscode · 62 tokens

chat-perf

Run chat perf benchmarks and memory leak checks against the local dev build or any published VS Code version. Use when investigating chat rendering regressions, validating perf-sensitive changes to chat UI, or checking for memory leaks in the chat response pipeline.

microsoft/vscode · 51 tokens

chat-pet-sprite-creation

Use when creating or changing VS Code chat pet sprite art, sprite sheets, state animations, eye treatments, Stable/Insiders variants, or pet transitions under src/vs/workbench/contrib/chat/browser/widget/media/chatPet.

microsoft/vscode · 53 tokens

cpu-profile-analysis

Analyze V8/Chrome CPU profiles (.cpuprofile) and DevTools trace files (Trace-.json). Use when: profiling performance, investigating slow functions, comparing code paths, finding bottlenecks, analyzing timeToRequest, understanding call trees from sampling profiler data, analyzing layout/paint/rendering, investigating…

microsoft/vscode · 71 tokens