essential-core-lifecycle

An always-on set of rules for carrying software changes through definition, planning, building, verification, review, and release. It connects each stage with practices such as specifications, tests, debugging, and Git version control.

In plain words
What is it for?
Use it as the default process for multi-file or risky work, from defining the change and breaking it into tasks to testing, reviewing, and preparing it for delivery.
Why use it?
It gives non-trivial changes a consistent path and requires evidence when behaviour changes or something breaks.

Cursor rule for Cursor

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 rules/mamahoos/dot-files/essential-core-lifecycle
Clone the repo
git clone --depth 1 https://github.com/mamahoos/dot-files

Made for: Cursor.

Per session 306 This file is loaded in full into every session.
When invoked 306 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 $0.00306 $0.00306
Opus 5 $0.00153 $0.00153
Sonnet 5 $0.00061 $0.00061
Haiku 4.5 $0.00031 $0.00031

Measured 2d ago against content hash 66934de30381, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

essential-core-lifecycle 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.

home/.cursor/rules/essential-core-lifecycle.mdc · 36 lines

What it actually says

Essential Core Lifecycle

This rule is always active and defines the minimum required workflow for non-trivial software changes.

Mandatory Core Skills

Apply these as the default lifecycle:

  1. Define: spec-driven-development
  2. Plan: planning-and-task-breakdown
  3. Build: incremental-implementation
  4. Verify: test-driven-development
  5. Verify (when broken): debugging-and-error-recovery
  6. Review: code-review-and-quality
  7. Ship: git-workflow-and-versioning

Enforcement Policy

  • For any non-simple change, start with Define and Plan before implementation.
  • For any multi-file or risky change, build in small slices and verify each slice.
  • For any behavior change or bug fix, provide test evidence.
  • If tests/build fail or behavior is unexpected, use systematic debugging before continuing.
  • Before merge or final delivery, run quality review.
  • Keep Git history clean: atomic commits, short-lived branches, and safe merge flow.
  • For deep guidance, load the corresponding SKILL.md files under .cursor/skills/.

Exception Policy

  • Tiny, obvious, low-risk edits may skip full lifecycle steps, but still require safe Git discipline.
  • If a step is intentionally skipped, briefly state why.
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. 2d ago First seen · 36 lines · 306 tokens per session scan A 66934de30381

Subscribe to this mod's changes

essential-core-lifecycle is a cursor rule published in the GitHub repository mamahoos/dot-files (3 stars, last pushed 2d ago), licensed MIT. It adds 306 tokens to every session, about $0.0015 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.