test-driven-development

test-driven-development is a skill for Claude Code, Codex from sivaguru-2113/Agent-persona. It costs 19 tokens per session (168 once invoked), scanned A, original, no licence file.

A test-first coding practice that requires a failing reproduction test or unit test before fixing a bug or adding a feature.

In plain words
What is it for?
Use it when fixing defects or building features that should be covered by automated tests.
Why use it?
It helps catch regressions and makes the intended behavior clear before code changes are made.

Skill for Claude CodeCodex

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

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/sivaguru-2113/agent-persona/test-driven-development
Any agent
npx skills add sivaguru-2113/Agent-persona --skill test-driven-development
Clone the repo
git clone --depth 1 https://github.com/sivaguru-2113/Agent-persona

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 test-driven-development

README.md
[![agentmods](https://agentmods.dev/badge/skills/sivaguru-2113/agent-persona/test-driven-development.svg)](https://agentmods.dev/skills/sivaguru-2113/agent-persona/test-driven-development)
Your own site
<a href="https://agentmods.dev/skills/sivaguru-2113/agent-persona/test-driven-development"><img src="https://agentmods.dev/badge/skills/sivaguru-2113/agent-persona/test-driven-development.svg" alt="Measured on agentmods" height="20"></a>
Per session 19 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 168 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00019 $0.00168
Opus 5 $0.00010 $0.00084
Sonnet 5 $0.00004 $0.00034
Haiku 4.5 $0.00002 $0.00017

Measured 5d ago against content hash 89d250f21193, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-06, from the pricing page.

Security

Grade A, and why

test-driven-development 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 5d 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/engineering/test-driven-development/SKILL.md · 19 lines

The source is not reproduced here

A licence we could not identify

The repository carries a LICENSE file, but it is custom or dual enough that GitHub cannot name it and neither can this catalogue. Unknown terms are not permission, so the body is not copied here. Read the licence at the source and decide for yourself.

Read it on GitHub

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. 5d ago First seen · 19 lines · 19 tokens per session scan A 89d250f21193

Subscribe to this mod's changes

test-driven-development is a skill published in the GitHub repository sivaguru-2113/Agent-persona (2 stars, last pushed 18d ago), with no licence file. It adds 19 tokens to every session and 168 once invoked, about $0.0001 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.