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.
npx agentmods add instructions/arc-mcp/arc-1/agents-mdgit clone --depth 1 https://github.com/arc-mcp/arc-1Wrote 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/arc-mcp/arc-1/agents-md)<a href="https://agentmods.dev/instructions/arc-mcp/arc-1/agents-md"><img src="https://agentmods.dev/badge/instructions/arc-mcp/arc-1/agents-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 | $0.12282 | $0.12282 |
| Opus 5 | $0.06141 | $0.06141 |
| Sonnet 5 | $0.02456 | $0.02456 |
| Haiku 4.5 | $0.01228 | $0.01228 |
Grade A, and why
arc-1 AGENTS.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 3d 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 — 368 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md
Guidance for AI coding agents (Claude Code, Codex, Cursor, Copilot, …) working in this repository.
Single source of truth — CLAUDE.md imports this file. Keep it terse: task→files + ≤1 gotcha per
row; verbose details and live-verified behaviors live in docs/dev-guide.md
(not auto-loaded — read the matching row there when working on one of these tasks).
Project Overview
ARC-1 is a TypeScript MCP (Model Context Protocol) server for SAP ABAP Development Tools (ADT).
It provides 12 intent-based tools (SAPRead, SAPSearch, SAPWrite, SAPActivate, SAPNavigate, SAPQuery,
SAPTransport, SAPGit, SAPContext, SAPLint, SAPDiagnose, SAPManage) for Claude and other MCP clients.
Distributed as npm package (arc-1) and Docker image (ghcr.io/arc-mcp/arc-1).
Design Principles
- Centralized admin control — managed service; server-wide safety ceiling (
allowWrites, package allowlists, SQL/data/transport/Git gates, deny actions); every call audited; per-user scopes restrict, never expand. - Per-user SAP identity by default — principal propagation maps each MCP user to their own SAP user. ADR-0007 permits only an explicit mutation-free multi-target Basic exception, labeled shared and never used as PP fallback.
- Token-efficient tools — 12 intent tools vs 200+ endpoints, with schema payload guarded by CI budgets; hyperfocused mode = 1 tool (~200 tokens); method-level surgery + context compression keep mid-tier LLMs viable.
- BTP-native deployment — Destination Service, Cloud Connector, XSUAA OAuth, BTP Audit Log; also Docker/npm/stdio.
- Multi-client, vendor-neutral — XSUAA OAuth + Entra ID OIDC + API key coexist; one instance serves Claude, Copilot Studio, VS Code, Gemini CLI, Cursor.
- Safe defaults, opt-in power — read-only by default; free SQL blocked; package allowlist defaults to
$TMP; everything forbidden until the admin allows it. - Single target by default; one experimental read-only BTP exception — ADR-0005 remains the rule for writable/general multi-system access. ADR-0006 permits only the default-off BTP CF mode with explicit pinned/aggregate targets under its mutation-free safety contract. ADR-0007 permits the default-off shared Basic identity only under its one-instance/lockout controls. Do not broaden either exception to writes or another discovery/auth model without a new ADR/security review.
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.
- 3d ago Changed · +4 lines · +91 tokens per session fef0a5917764
- 4d ago First seen · 364 lines · 12,191 tokens per session scan A cdbc061a05ee
arc-1 AGENTS.md is an instructions file published in the GitHub repository arc-mcp/arc-1 (174 stars, last pushed 3d ago), licensed MIT. It adds 12,282 tokens to every session, about $0.0614 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.
Other instructions, from other repositories
vscode accessibility.instructions.md
Use when implementing accessibility features, ARIA labels, screen reader support, accessible help dialogs, or keybinding scoping for accessibility. Covers AccessibleContentProvider, CONTEXTACCESSIBILITYMODEENABLED, verbosity settings, and announcement patterns.
vscode design-philosophy.instructions.md
VS Code design philosophy — the shared Values→Principles→Moves vocabulary for reasoning about UI in design terms rather than raw pixels. Use when creating, editing, or reviewing any visual surface (CSS, DOM, theming, icons, motion). Name the value/principle before reaching for a token.
deepagents AGENTS.md
AGENTS.md instructions for langchain-ai/deepagents, covering global development guidelines for the deep agents monorepo, corridor security analysis, development workflow, suppressing ruff rules and pr conventions.
ui-components AGENTS.md
AGENTS.md instructions for starc007/ui-components, covering beui v2 — agent guide, commands, layout, component catalog and components (motion category — primitives).
windmill AGENTS.md
AGENTS.md instructions for windmill-labs/windmill, covering windmill, workflow, documentation, dev environment and per-worktree ports and database.
walkerOS CLAUDE.md
Claude Code instructions for elbwalker/walkerOS, covering claude.md and important: use agent.md.