arc-relay copilot-instructions.md

arc-relay copilot-instructions.md is an instructions file for GitHub Copilot from comma-compliance/arc-relay. It costs 367 tokens per session, scanned A, original, MIT.

Project instructions for Arc Relay, an open-source control service for AI tool calls. It provides authentication, policy checks, traffic interception, and archiving around MCP, a standard way for AI assistants to use external tools.

In plain words
What is it for?
They guide work on the relay and sync command-line programs, middleware, proxy connections, SQLite storage, configuration, web handlers, and tests.
Why use it?
They give agents the project structure, build requirements, and coding patterns needed to change the Go service safely.

Instructions file for GitHub Copilot

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 instructions/comma-compliance/arc-relay/copilot-instructions
Clone the repo
git clone --depth 1 https://github.com/comma-compliance/arc-relay

Made for: GitHub Copilot.

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.

agentmods badge for arc-relay copilot-instructions.md

README.md
[![agentmods](https://agentmods.dev/badge/instructions/comma-compliance/arc-relay/copilot-instructions.svg)](https://agentmods.dev/instructions/comma-compliance/arc-relay/copilot-instructions)
Your own site
<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="Measured on agentmods" height="20"></a>
Per session 367 This file is loaded in full into every session.
When invoked 367 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 $0.00367 $0.00367
Opus 5 $0.00183 $0.00183
Sonnet 5 $0.00073 $0.00073
Haiku 4.5 $0.00037 $0.00037

Measured 5d ago against content hash 0f37debd4a50, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

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 5d 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.

.github/copilot-instructions.md · 32 lines

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 migrations
  • internal/web/ - HTTP handlers and server-rendered HTML templates
  • internal/config/ - TOML config + ARC_RELAY_* env var overrides
  • internal/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 ProcessRequest and ProcessResponse on mcp.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
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. 5d ago First seen · 32 lines · 367 tokens per session scan A 0f37debd4a50

Subscribe to this mod's changes

arc-relay copilot-instructions.md is an instructions file published in the GitHub repository comma-compliance/arc-relay (57 stars, last pushed 5d ago), licensed MIT. It adds 367 tokens to every session, about $0.0018 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 2026-08-30.