agentmods.dev

defensive-development

defensive-development is a skill for Claude Code, Codex from microbians/AI.SKILLS. It costs 33 tokens per session (4,592 once invoked), scanned A, original, no licence file.

A set of coding practices focused on checking work before changing code. It emphasizes reading files, checking references, confirming API names, and verifying refactors.

In plain words
What is it for?
Use it when inspecting, editing, or refactoring code and when checking that the resulting changes are correct.
Why use it?
It helps prevent changes based on guesses, incorrect API names, or incomplete understanding of how code is used.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

not rated 5repo yesterday A scan 33 tokens no licence

Good fit Use it when inspecting, editing, or refactoring code and when checking that the resulting changes are correct.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/microbians/ai.skills/defensive-development
View source ↗ microbians/AI.SKILLS
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 microbians/AI.SKILLS --skill defensive-development
Clone the repo
git clone --depth 1 https://github.com/microbians/AI.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 defensive-development

README.md
[![agentmods](https://agentmods.dev/badge/skills/microbians/ai.skills/defensive-development/github.svg)](https://agentmods.dev/skills/microbians/ai.skills/defensive-development)
Your own site
<a href="https://agentmods.dev/skills/microbians/ai.skills/defensive-development"><img src="https://agentmods.dev/badge/skills/microbians/ai.skills/defensive-development/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 defensive-development

Your own site · 80×15
<a href="https://agentmods.dev/skills/microbians/ai.skills/defensive-development"><img src="https://agentmods.dev/badge/skills/microbians/ai.skills/defensive-development.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 33 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,592 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 1 finding. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown 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 $0.00033 $0.04592
Opus 5.5 $0.00013 $0.01837
Sonnet 5.5 $0.00007 $0.00918
Haiku 4.5 $0.00003 $0.00459

Measured 2mo ago against content hash e3926f4ed61b, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

defensive-development scanned grade A with 1 finding 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 2mo 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.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

curl -v http://localhost:3000/api/endpoint
skills/defensive-development/SKILL.md · 745 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

Files

What ships with it

1 file 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. 2mo ago First seen · 745 lines · 33 tokens per session scan A e3926f4ed61b

Subscribe to this mod's changes

defensive-development is a skill published in the GitHub repository microbians/AI.SKILLS (5 stars, last pushed yesterday), with no licence file. It adds 33 tokens to every session and 4,592 once invoked, about $0.0001 per session on Opus 5.5. A static security scan graded it A with 1 finding (makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

Related

defensive-development compared with skills from other repositories

defensive-development next to 6 skills from other repositories
ModTypeStarsLast pushLicenceScanTokensWorks with
defensive-developmentmicrobians/AI.SKILLSSkill5yesterdaynoneA33Claude Code, Codex
imagegenopenai/codexSkill134ktodayApache-2.0A113Codex
local-ai-agentsmicrosoft/ai-agents-for-beginnersSkill79kyesterdayMITA200Claude Code, Codex
playwright-climicrosoft/playwrightSkill100kyesterdayApache-2.0A19Claude Code
browser-automationopenclaw/openclawSkill394ktodayMITA36Claude Code
systematic-debuggingobra/superpowersSkill314k4d agoMITA21Claude Code
next-cache-components-adoptionvercel/next.jsSkill143ktodayMITA95Claude Code