add AGENTS.md

Repository instructions for ADD, a specification-first method for building software with human and AI collaborators. They define a step-by-step path from requirements and feature specifications to plans, tests, and implementation.

In plain words
What is it for?
Running requirements interviews, preparing project specifications and plans, writing user and automated tests, and setting limits on an agent’s autonomy.
Why use it?
They prevent code from being written without an agreed specification and keep production releases and merges under human control.

Instructions file for CodexOpenCode

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 instructions/mountainunicorn/add/agents-md
Clone the repo
git clone --depth 1 https://github.com/MountainUnicorn/add

Made for: Codex, OpenCode.

Per session 462 This file is loaded in full into every session.
When invoked 462 The same file — it is already loaded in full.
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 $0.00462 $0.00462
Opus 5 $0.00231 $0.00231
Sonnet 5 $0.00092 $0.00092
Haiku 4.5 $0.00046 $0.00046

Measured yesterday against content hash 339832eb2a8f, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

add AGENTS.md 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 yesterday.

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.md · 35 lines

What it actually says

ADD

ADD (Agent Driven Development) solves this by bringing structured, specification-driven SDLC practices to AI-native development—just as TDD revolutionized testing and DDD revolutionized domain modeling, ADD provides a proven methodology for human-AI collaboration at scale.

Engagement Protocol

The human is the architect and decision maker; the agent is the builder. Gather requirements via one-question-at-a-time interviews. Never batch questions. When stepping away, declare autonomy ceilings explicitly — the agent may climb local → dev → staging but never merges to main or ships to production without human approval.

Spec-First Invariants

Every feature flows through the document hierarchy: PRD → Feature Spec → Implementation Plan → User Test Cases → Automated Tests → Implementation. No link may be skipped. Specs live in specs/, plans in docs/plans/. Code changes without a corresponding spec are rejected on review.

Maturity & Autonomy Ceiling

Project maturity: beta.

  • local: auto-promotion not declared.

Production deploys and merges to the default branch always require human approval.

Currently Active Spec

None in flight. Last shipped: specs/codex-agent-prefixing.md (v0.11.0), specs/init-defaults.md, specs/doctor.md, specs/codex-install-manifest.md (v0.10.2). Current focus: GA promotion (docs/milestones/v1.0-ga.md) — marketplace approval pending.

Pointers

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. yesterday First seen · 35 lines · 462 tokens per session scan A 339832eb2a8f

Subscribe to this mod's changes

add AGENTS.md is an instructions file published in the GitHub repository MountainUnicorn/add (11 stars, last pushed 1mo ago), licensed MIT. It adds 462 tokens to every session, about $0.0023 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.