Borrowing it
Nothing to install: this file belongs to railyard-dev/railguard. 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/railyard-dev/railguard/main/CLAUDE.mdgit clone --depth 1 https://github.com/railyard-dev/railguardWrote 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/railyard-dev/railguard/claude-md)<a href="https://agentmods.dev/instructions/railyard-dev/railguard/claude-md"><img src="https://agentmods.dev/badge/instructions/railyard-dev/railguard/claude-md/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.
<a href="https://agentmods.dev/instructions/railyard-dev/railguard/claude-md"><img src="https://agentmods.dev/badge/instructions/railyard-dev/railguard/claude-md.svg" alt="Reviewed on agentmods" width="80" 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 | $0.00627 | $0.00627 |
| Opus 5.5 | $0.00251 | $0.00251 |
| Sonnet 5.5 | $0.00125 | $0.00125 |
| Haiku 4.5 | $0.00063 | $0.00063 |
Grade B, and why
railguard CLAUDE.md scanned grade B with 1 finding 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 1mo 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.
Reads agent configuration directoriesmediumAgent snooping
.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.
- Modify `~/.claude/settings.json` — it will be blocked. How it starts
The opening of the file, as written. The whole thing — 48 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Railguard — Active Guardrails
Railguard is monitoring this session. Every tool call (Bash, Write, Edit, Read) passes through Railguard before execution.
What you need to know
- Some commands will be blocked. If you see a "denied" response from a hook, it means Railguard blocked the command. Do NOT retry the same command — find a safer alternative.
- Some commands require human approval. If you see an "ask" response, the human will be prompted to approve or deny.
- File writes are snapshotted. Every Write/Edit you make is backed up before execution. The human can rollback any change.
- Everything is logged. All tool calls and decisions are recorded in
.railguard/traces/.
If something goes wrong
If the human asks you to undo changes, fix a mistake, or rollback:
-
Get context first. Run:
railguard context --session $SESSION_ID --verboseThis shows you exactly what changed, diffs, blocked commands, and available rollback commands. -
Check what changed. Run:
railguard diff --session $SESSION_IDOr for a specific file:railguard diff --session $SESSION_ID --file <path> -
Rollback options:
- Undo the last edit:
railguard rollback --session $SESSION_ID --steps 1 - Undo the last N edits:
railguard rollback --session $SESSION_ID --steps N - Restore a specific file:
railguard rollback --session $SESSION_ID --file <path> - Restore everything:
railguard rollback --session $SESSION_ID - Restore a specific snapshot:
railguard rollback --session $SESSION_ID --id <snapshot-id>
- Undo the last edit:
-
Find your session ID. Run:
railguard logThis lists all sessions. Pick the most recent one.
Configuring Railguard
You can help the user customize their Railguard policy. This is encouraged:
- Read
railguard.yamlto understand the current policy. - Propose edits to
railguard.yaml— the user will be prompted to approve before any change is applied. - Run
railguard initto generate a starterrailguard.yamlif one doesn't exist (user approves). - Run
railguard statusto show the current protection state. All changes to Railguard policy require explicit human approval. You generate the change, the user reviews and accepts or rejects it. Changes take effect on the next tool call — no restart needed.
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.
- 1mo ago First seen · 48 lines · 627 tokens per session scan B 78ddb4ab9d67
railguard CLAUDE.md is an instructions file published in the GitHub repository railyard-dev/railguard (39 stars, last pushed 7mo ago), licensed MIT. It adds 627 tokens to every session, about $0.0025 per session on Opus 5.5. A static security scan graded it B with 1 finding (reads agent configuration directories). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other instructions, from other repositories
plan-forge dapr.instructions.md
Dapr patterns for .NET — building blocks, component config, sidecar architecture, multi-tenant isolation, workflows, state management, secrets.
plan-forge blazor-fluent-ui.instructions.md
Blazor Server + Microsoft Fluent UI patterns — component layering, state, lifecycle, accessibility. Auto-loads when editing .razor / .razor.cs files.
plan-forge landing-zone.instructions.md
Azure Landing Zone baselines — identity, network, policy, management, security, tagging, subscription organization.
plan-forge policy.instructions.md
Azure Policy and Initiative compliance — definitions, assignment, compliance state, exemptions, remediation tasks.
plan-forge api-patterns.instructions.md
API patterns for .NET — REST conventions, ProblemDetails, pagination, versioning, error responses.
plan-forge database.instructions.md
Database patterns for .NET — Dapper/EF Core 10, parameterized queries, migration strategy.