Borrowing it
Nothing to install: this file belongs to fjpulidop/specrails-core. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/fjpulidop/specrails-core/main/CLAUDE.mdgit clone --depth 1 https://github.com/fjpulidop/specrails-coreWrote 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.
[](https://agentmods.dev/instructions/fjpulidop/specrails-core/claude-md)<a href="https://agentmods.dev/instructions/fjpulidop/specrails-core/claude-md"><img src="https://agentmods.dev/badge/instructions/fjpulidop/specrails-core/claude-md.svg" alt="Measured on agentmods" height="20"></a>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 | $0.01873 | $0.01873 |
| Opus 5 | $0.00937 | $0.00937 |
| Sonnet 5 | $0.00375 | $0.00375 |
| Haiku 4.5 | $0.00187 | $0.00187 |
Grade A, and why
specrails-core CLAUDE.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 6d 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.
specrails-core
Agent Workflow System installer for Claude Code. Installs a spec-driven development workflow into any repository: three OpenSpec-integrated AI agents (architect, developer, reviewer), orchestration commands, and per-layer coding conventions — all adapted to the target codebase automatically. Extend the core trio with user-owned custom-* agents via profiles.
Stack
| Layer | Tech |
|---|---|
| Installer | TypeScript / Node ≥ 20.19.0 (cross-platform: macOS, Linux, Windows) |
| Templates | Markdown with {{PLACEHOLDER}} substitution |
| Commands | Claude Code slash commands (Markdown) |
| Prompts | Markdown guide prompts |
| Spec system | OpenSpec (YAML + Markdown) |
| Tests | vitest (cross-platform CI matrix) |
Repo layout
specrails-core/
├── bin/
│ ├── specrails-core.mjs # CLI entry point (ESM dispatcher)
│ └── tui-installer.mjs # interactive TUI writer for install-config.yaml
├── src/
│ └── installer/ # TypeScript installer (compiled → dist/)
│ ├── cli.ts # main() + arg parser
│ ├── commands/ # init / update / doctor
│ ├── phases/ # prereqs, provider-detect, scaffold, manifest, install-config
│ └── util/ # logger, exec, fs, git, prompts, template, errors, paths
├── dist/ # tsc output (npm-published, gitignored)
├── README.md # User-facing documentation
├── templates/ # Source templates for agents, commands, rules
│ ├── agents/ # Agent prompt templates (sr-architect/developer/reviewer only)
│ ├── commands/ # Workflow command templates
│ ├── rules/ # Per-layer convention template
│ ├── profiles/ # Default profile (baseline trio)
│ ├── claude-md/ # Root CLAUDE.md template
│ └── settings/ # Settings template
├── commands/ # Bundled slash-command bodies (doctor.md)
├── schemas/ # JSON Schema for profile validation
├── openspec/ # OpenSpec config, specs, and changes
└── .specrails/ # Runtime config (gitignored)
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.
- 6d ago First seen · 134 lines · 1,873 tokens per session scan A 3295e407b01c
specrails-core CLAUDE.md is an instructions file published in the GitHub repository fjpulidop/specrails-core (9 stars, last pushed 1mo ago), licensed MIT. It adds 1,873 tokens to every session, about $0.0094 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.
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