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 agentmods add skills/devnomad-byte/techneering/redgreennpx skills add devnomad-byte/techneering --skill redgreengit clone --depth 1 https://github.com/devnomad-byte/techneeringWhat 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 | $0.00016 | $0.00995 |
| Opus 5 | $0.00008 | $0.00498 |
| Sonnet 5 | $0.00003 | $0.00199 |
| Haiku 4.5 | $0.00002 | $0.00100 |
Grade A, and why
redgreen 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 2d 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 — 134 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Test-Driven Development (TDD)
Core Principle
NO PRODUCTION CODE WITHOUT A FAILING TEST FIRST.
If you didn't watch the test fail, you don't know if it tests the right thing.
Violating the letter of the rules is violating the spirit of the rules.
The Iron Law
NO PRODUCTION CODE WITHOUT A FAILING TEST FIRST
Write code before the test? Delete it. Start over.
Red-Green-Refactor
digraph tdd_cycle {
rankdir=LR;
red [label="RED\nWrite failing test", shape=box];
verify_red [label="Verify fails\ncorrectly", shape=diamond];
green [label="GREEN\nMinimal code", shape=box];
verify_green [label="Verify passes\nAll green", shape=diamond];
refactor [label="REFACTOR\nClean up", shape=box];
next [label="Next", shape=ellipse];
red -> verify_red;
verify_red -> green [label="yes"];
verify_red -> red [label="wrong failure"];
green -> verify_green;
verify_green -> refactor [label="yes"];
verify_green -> green [label="no"];
refactor -> verify_green [label="stay green"];
verify_green -> next;
next -> red;
}
RED - Write Failing Test
Write one minimal test showing what should happen.
- One behavior
- Clear name
- Real code (no mocks unless unavoidable)
Verify RED - Watch It Fail
MANDATORY. Never skip.
Confirm: Test fails (not errors), failure message is expected, fails because feature missing.
GREEN - Minimal Code
Write simplest code to pass the test. Don't add features, refactor other code, or "improve" beyond the test.
Verify GREEN - Watch It Pass
MANDATORY. Confirm test passes, other tests still pass, output pristine.
REFACTOR - Clean Up
After green only: Remove duplication, improve names, extract helpers. Keep tests green.
Testing Anti-Patterns
Read testing-anti-patterns.md in this directory for detailed guidance on:
- Testing mock behavior instead of real behavior
- Adding test-only methods to production classes
- Mocking without understanding dependencies
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.
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.
- 2d ago First seen · 134 lines · 16 tokens per session scan A 8d8627c3878e
redgreen is a skill published in the GitHub repository devnomad-byte/techneering (13 stars, last pushed 2mo ago), licensed MIT. It adds 16 tokens to every session and 995 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 2026-08-30.
Other skills, from other repositories
tdd-rust
TDD workflow for RTK filter development. Red-Green-Refactor with Rust idioms. Real fixtures, token savings assertions, snapshot tests with insta. Auto-triggers on new filter implementation.
rtk-tdd
Enforces TDD (Red-Green-Refactor) for Rust development. Auto-triggers on implementation, testing, refactoring, and bug fixing tasks. Provides Rust-idiomatic testing patterns with anyhow/thiserror, cfg(test), and Arrange-Act-Assert workflow.
test-driven-development
在实现任何功能或修复 bug 时使用，在编写实现代码之前.
test-driven-development
Use when the user explicitly requests strict or test-first TDD, or when the current conversation already contains an explicit TDD Route: strict decision from another Aegis workflow.
build-executor
Govern implementation from an approved execution contract. Invoke when execution-contract.md is approved and the user wants disciplined build work, TDD execution, or guarded batch-by-batch implementation.
agent-teams
Claude Code Agent Teams - default team-based development with strict TDD pipeline enforcement.