Borrowing it
Nothing to install: this file belongs to comma-compliance/arc-relay. 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/comma-compliance/arc-relay/main/.github/copilot-instructions.mdgit clone --depth 1 https://github.com/comma-compliance/arc-relayWrote 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/comma-compliance/arc-relay/copilot-instructions)<a href="https://agentmods.dev/instructions/comma-compliance/arc-relay/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/comma-compliance/arc-relay/copilot-instructions/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/comma-compliance/arc-relay/copilot-instructions"><img src="https://agentmods.dev/badge/instructions/comma-compliance/arc-relay/copilot-instructions.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 | $0.00367 | $0.00367 |
| Opus 5.5 | $0.00147 | $0.00147 |
| Sonnet 5.5 | $0.00073 | $0.00073 |
| Haiku 4.5 | $0.00037 | $0.00037 |
Grade A, and why
arc-relay copilot-instructions.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 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.
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.
What it actually says
Arc Relay - AI Assistant Context
Arc Relay is an open-source MCP (Model Context Protocol) control plane written in Go. It provides auth, policy controls, traffic interception, and archiving for AI tool calls.
Project Structure
cmd/arc-relay/- Server binary (CGO required for SQLite)cmd/arc-sync/- CLI tool for syncing MCP servers to projects (pure Go)internal/middleware/- Bidirectional middleware pipeline (archive, sanitizer, sizer, alerter)internal/proxy/- MCP proxy backends (stdio bridge, HTTP, remote with OAuth)internal/store/- SQLite persistence layer with migrationsinternal/web/- HTTP handlers and server-rendered HTML templatesinternal/config/- TOML config + ARC_RELAY_* env var overridesinternal/cli/- CLI packages (config, sync, project detection)
Building
CGO_ENABLED=1 go build ./cmd/arc-relay # Server (needs gcc, libsqlite3-dev)
CGO_ENABLED=0 go build ./cmd/arc-sync # CLI (pure Go, cross-platform)
go test ./... # Run all tests
go vet ./... # Static analysis
Key Patterns
- Middleware implements
ProcessRequestandProcessResponseonmcp.Request/mcp.Response - Request middleware runs in order; response middleware runs in reverse order
- Config: TOML file + env var overrides (ARC_RELAY_, ARC_SYNC_)
- Auth: session cookies (web UI) + Bearer API keys (proxy)
- Archive dispatcher uses SQLite queue with retry backoff and circuit breaker
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 · 32 lines · 367 tokens per session scan A 0f37debd4a50
arc-relay copilot-instructions.md is an instructions file published in the GitHub repository comma-compliance/arc-relay (53 stars, last pushed 23d ago), licensed MIT. It adds 367 tokens to every session, about $0.0015 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 2026-08-30.
Other instructions, from other repositories
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, cache eligibility and rollout and applying the notice (cutover).
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.
vscode copilot-instructions.md
Copilot instructions for microsoft/vscode, covering vs code copilot instructions, project overview, root folders, core architecture (src/ folder) and built-in extensions (extensions/ folder).
vscode design-tokens.instructions.md
Design-system size tokens (spacing, corner radius, font size, codicon size, stroke). Use when writing or editing CSS to size, space, or round UI — prefer the --vscode- token vars over hardcoded px values.