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/block/buzz/agents-mdgit clone --depth 1 https://github.com/block/buzzWhat 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 | $0.07876 | $0.07876 |
| Opus 5 | $0.03938 | $0.03938 |
| Sonnet 5 | $0.01575 | $0.01575 |
| Haiku 4.5 | $0.00788 | $0.00788 |
Grade A, and why
buzz 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 yesterday.
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 — 649 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md — AI Agent Contributor Guide
This guide is for AI agents contributing to the Buzz codebase. It covers agent-specific context and conventions. For general contributor info (setup, code style, PR process, architecture), see CONTRIBUTING.md.
Product Contract
Before planning or reviewing a non-trivial change:
- Read VISION.md.
- Read the
VISION_*.mddocuments relevant to the affected product surface. - Read the applicable guidance in TESTING.md and any
package-local
TESTING.md. - Check that the proposed design advances, or at least does not contradict, that product intent. Call out any intentional tension explicitly.
Implementation describes the product today; the vision documents describe the product it is becoming. A locally correct change can still be wrong if it works against that direction. Scale validation to the change's risk and exercise the real workflow for user-visible or integration behavior when practical; green CI and runtime evidence answer different questions.
Ecosystem
Buzz spans five repos. This one (block/buzz) is the OSS source for the relay, desktop, mobile, and CLI. The others handle internal builds and deployment:
| Repo | Purpose |
|---|---|
| block/buzz | OSS source — relay, desktop app, mobile app, CLI, agent harness |
| squareup/buzz-releases | Buildkite pipelines producing Block-signed macOS + iOS builds with -block desktop version suffix |
| squareup/sprout-oss | CI pipeline building the relay Docker image and pushing to internal ECR |
| squareup/block-coder-tf-stacks | Terraform + ArgoCD deploying the relay to the staging Kubernetes cluster |
| squareup/sprout-backend-blox | Desktop backend provider script connecting Blox workstation agents to the relay |
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.
- yesterday First seen · 649 lines · 7,876 tokens per session scan A 844a0a1a500e
buzz AGENTS.md is an instructions file published in the GitHub repository block/buzz (31,513 stars, last pushed 2d ago), licensed Apache-2.0. It adds 7,876 tokens to every session, about $0.0394 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
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
buildNext
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
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, applying the notice (cutover) and fallback chain (never fail the build).
spec-kit AGENTS.md
Instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.
langchain 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.