Borrowing it
Nothing to install: this file belongs to NexaDuo/mARC. 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/NexaDuo/mARC/main/AGENTS.mdgit clone --depth 1 https://github.com/NexaDuo/mARCWrote 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/nexaduo/marc/agents-md)<a href="https://agentmods.dev/instructions/nexaduo/marc/agents-md"><img src="https://agentmods.dev/badge/instructions/nexaduo/marc/agents-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/nexaduo/marc/agents-md"><img src="https://agentmods.dev/badge/instructions/nexaduo/marc/agents-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 | $0.02461 | $0.02461 |
| Opus 5.5 | $0.00984 | $0.00984 |
| Sonnet 5.5 | $0.00492 | $0.00492 |
| Haiku 4.5 | $0.00246 | $0.00246 |
Grade A, and why
mARC 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 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.
How it starts
The opening of the file, as written. The whole thing — 143 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md
mARC (Multi-Agent Relay Control) is a Claude Code plugin + self-marketplace
that packages a portable, cross-repo AI engineering team: @techlead (channel
operator) convenes specialists @dev, @sre, @design, @sec, @research. The
team's
governance travels via one plugin; each consuming repo keeps its own facts.
This repo is special: it is BOTH the product's source AND where the team dogfoods on itself. Self-improvement lessons legitimately flush to source here — the one context where that is allowed (see Constraints).
Architecture
- Plugin lives at
harnesses/claude-code/marc/; the marketplace manifest is at repo root.claude-plugin/marketplace.json(namenexaduo, pluginmarc→ installmarc@nexaduo, invoke/marc:tech-lead). - Leaders = skills (
skills/<leader>/, invoked/marc:<leader>); specialists = a shared flat pool (agents/*.md). Any leader convenes any specialist. - Nesting under
harnesses/<harness>/reserves the namespace for future non–Claude-Code harnesses. The growth model is indocs/ARCHITECTURE.md— don't duplicate it here. core/is the editable source;harnesses/*/marc/(skills, agents) is compiled output — never hand-edit it. Runscripts/compile_prompts.pyto regenerate fromcore/+ each harness'scompile.json, and commit the regenerated files.
Operating principles
These distill a comparative study of agent-orchestration frameworks (OpenHands, MetaGPT, CrewAI, Claude Code Agent Teams) down to what holds for mARC:
- Stateless dispatch / context hygiene. Specialists run fresh per task; durable state lives in git, the board/issues, and this file — not in long conversations.
- Spec-driven leverage. A vague task propagates destructively across parallel agents. The tech-lead's main leverage is spec clarity + acceptance criteria before dispatch (the sufficiency gate).
- Dispatch in the background; isolate parallel writers. Synchronous dispatch blocks the operator channel — fan out in background and track via notifications. When specialists edit files concurrently, isolate them (git worktrees) to avoid clobbering.
- Bounded loops. Cap runaway debugging; stop and surface rather than burn tokens in an infinite fix loop.
- Tiered, size-capped memory with absolute decay. Local/session memory is
bounded (≤ 200 lines / ~2 KB) and organized as a lightweight recall index
separating permanent invariants (
[PINNED]) from time-bound entries with absolute dates ([EXPIRES: YYYY-MM-DD]). Substantive findings or oversized bodies spill into PR-gated artifacts (docs/marc/or consumer workspace) and are fetched on demand, never loaded unconditionally. - No self-merge; independent review. Every PR gets a security pass; the author can't self-approve.
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 · 143 lines · 2,461 tokens per session scan A bd669de17c8c
mARC AGENTS.md is an instructions file published in the GitHub repository NexaDuo/mARC (7 stars, last pushed 5d ago), licensed MIT. It adds 2,461 tokens to every session, about $0.0098 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 2026-08-31.
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).
deepseek-harness AGENTS.md
AGENTS.md instructions for deepseek-ai/deepseek-harness, covering agents.md, pre-stable apis and released session data, repository layout, commands and host sandbox failures.