What is ci-first-philosophy?

A development approach that checks new code through integration and end-to-end tests in continuous integration (CI), the automated checks run by services such as GitHub Actions. End-to-end tests follow complete user journeys, while integration tests check real connections between parts such as databases and APIs.

Use it when adding features or building applications to reason about system-wide effects, plan realistic test data, and validate complete workflows in CI.

It reduces the risk that code passes isolated tests but fails when the full application and its external services work together.

How nbaertsch/Mythic-MCP configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to nbaertsch/Mythic-MCP. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/nbaertsch/Mythic-MCP/main/.claude/skills/ci-first-philosophy/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/nbaertsch/Mythic-MCP

Made for: Claude Code.

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/nbaertsch/mythic-mcp/ci-first-philosophy/github.svg)](https://agentmods.dev/skills/nbaertsch/mythic-mcp/ci-first-philosophy)

Your own site

<a href="https://agentmods.dev/skills/nbaertsch/mythic-mcp/ci-first-philosophy"><img src="https://agentmods.dev/badge/skills/nbaertsch/mythic-mcp/ci-first-philosophy/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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/nbaertsch/mythic-mcp/ci-first-philosophy"><img src="https://agentmods.dev/badge/skills/nbaertsch/mythic-mcp/ci-first-philosophy.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 69 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 3,306 The whole file, excluding the scripts and references it only reads on demand.

Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.

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.

Model	Per session	Once invoked
Fable 5.1	$0.00069	$0.03306
Opus 5.5	$0.00028	$0.01322
Sonnet 5.5	$0.00014	$0.00661
Haiku 4.5	$0.00007	$0.00331

Measured 2mo ago against content hash 3e2e0dc613a0, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

ci-first-philosophy 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 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.

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.

.claude/skills/ci-first-philosophy/SKILL.md · 489 lines

How it starts

The opening of the file, as written. The whole thing — 489 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CI-First Development Philosophy

A proven methodology that shifts from isolated unit-test-driven TDD to comprehensive CI-validated, integration-first development.

Core Principles

1. Reason Before Coding

Always start by understanding the system, not just the function:

What is the desired outcome for the user/system?
What are the integration points (databases, APIs, services)?
What edge cases exist at integration boundaries?
What test data is needed for realistic testing?
How will this work in the full system context?

Pattern:

User Request → System Thinking → Integration Analysis → Test Planning → Implementation
     ↓              ↓                    ↓                    ↓              ↓
  "Add login"   Auth flow         DB, sessions         Test users    Code + Tests

2. Integration Over Isolation

Test Pyramid - Inverted for CI-First:

┌─────────────────────────────┐
│    End-to-End Tests         │  ← MOST IMPORTANT
│    (Full system flows)      │     Test real user journeys
├─────────────────────────────┤
│   Integration Tests         │  ← CORE VALIDATION
│   (Service interactions)    │     Real DB, APIs, services
├─────────────────────────────┤
│      Unit Tests             │  ← TARGETED ONLY
│   (Complex logic only)      │     Not exhaustive
└─────────────────────────────┘

Key Insight: Unit tests alone miss real-world issues. Integration and E2E tests catch:

Database constraint violations
API contract mismatches
Race conditions
Configuration errors
Service interaction bugs
Deployment issues

3. CI as Source of Truth

If it passes in CI, it works. If it fails in CI, it's broken.

CI tests run in production-like environment
CI validates full system integration
CI catches environment-specific issues
Local tests can lie (wrong versions, cached state, etc.)

Workflow:

1. Make change
2. Commit and push
3. Watch CI run
4. If fails → analyze, fix, repeat
5. If passes → trust it

Read the full file on GitHub · 489 lines

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.

2mo ago First seen · 489 lines · 69 tokens per session scan A 3e2e0dc613a0

Subscribe to this mod's changes

ci-first-philosophy is a skill published in the GitHub repository nbaertsch/Mythic-MCP (10 stars, last pushed 8mo ago), licensed MIT. It adds 69 tokens to every session and 3,306 once invoked, about $0.0003 per session on Opus 5.5. 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.

CI and CD DevOps and cloud E2E testing Testing

e2e-testing

Use when reviewing CI coverage, automated checks, or test strategy related to Implement end-to-end testing. Focus on whether the rule is continuously verified, not just documented.

thedaviddias/Front-End-Checklist · 38 tokens

azure-microsoft-playwright-testing-ts

Run Playwright tests at scale using Azure Playwright Workspaces (formerly Microsoft Playwright Testing). Use when scaling browser tests across cloud-hosted browsers, integrating with CI/CD pipelines, or publishing test results to the Azure portal.

microsoft/skills · 53 tokens

mirrord-chaos

Help users chaos test their app with mirrord: inject artificial latency or connection errors into a mirrord session's outgoing traffic via per-session chaos rules managed with the mirrord chaos CLI. Use when a user wants to add latency or delay to outgoing connections or a dependency (e.g. a slow database), simulate…

metalbear-co/mirrord · 119 tokens

Mythic-MCP: Skill for Claude Code