ai-md-stack

Base, standard configuration I run with Claude Code: a single canonical AGENTS.md shared with OpenCode and AbacusAI CLI, plus a small enforcement layer of Claude Code hooks.

Full writeup: My AI setup: Claude, Abacus, and OpenCode.

Tools this targets

• Claude Code
• OpenCode
• AbacusAI CLI

Layout

ai-md-stack/
├── AGENTS.md                        canonical instruction file
├── CLAUDE.md -> AGENTS.md           symlink, same content
├── settings.example.json            hook registration for Claude Code
├── hooks/                           Claude Code enforcement layer
│   ├── _common.sh
│   ├── mutation-guard.sh
│   ├── commit-guard.sh
│   ├── session-context.sh
│   └── redact-secrets.sh
└── examples/opencode-with-global/   recovers the global AGENTS.md in OpenCode
    ├── opencode.json
    ├── AGENTS.md
    └── README.md

AGENTS.md / CLAUDE.md

CLAUDE.md is a relative symlink to AGENTS.md (ln -s AGENTS.md CLAUDE.md), so both Claude Code and OpenCode read the same file. Claude Code only recognizes CLAUDE.md natively; OpenCode and AbacusAI CLI read AGENTS.md directly.

This part is shared: AbacusAI CLI only loads AGENTS.md from the project workspace, not from a user-level global path, so its copy has to live in each project root rather than symlinked from a single global location.

The file itself is based on the structure from andrej-karpathy-skills, evolved further through running Claude Code across several different environments.

OpenCode doesn't concatenate local and global instructions the way Claude Code does: once a project has its own AGENTS.md, the global one is ignored entirely. See examples/opencode-with-global/ for the opencode.json workaround.

hooks/

AGENTS.md/CLAUDE.md is context, not applied configuration: the model tries to follow it, but nothing guarantees it remembers a rule in a long session. This is the enforcement layer for the rules that must hold regardless.

Claude Code only. Doesn't port to OpenCode's plugin system (tool.execute.before/after) or to AbacusAI CLI, which has no documented hook mechanism.

• _common.sh: shared is_command_invoked() helper, so a guard fires on terraform plan but not on jq --arg c 'terraform plan'.
• mutation-guard.sh (PreToolUse): blocks write verbs on aws/gh/kubectl/terraform, with an explicit ALLOW_MUTATION=1 escape hatch.
• commit-guard.sh (PreToolUse): validates git commit subjects against the Conventional Commits rules already documented in AGENTS.md.
• session-context.sh (SessionStart): injects current branch, dirty file count, and last commit into context.
• redact-secrets.sh (PostToolUse): redacts leaked secrets (GitHub/OpenAI/Anthropic tokens, AWS access keys, PEM blocks) from command output, strips known noise, and truncates large output, via updatedToolOutput.

All shellcheck-clean and bash -n validated.

RTK

Also running RTK (Rust Token Killer), a CLI proxy that rewrites shell commands before execution to cut token usage. Registered as its own PreToolUse hook, separate from the ones in hooks/.

Usage

mkdir -p ~/.claude ~/.config/opencode
cp AGENTS.md ~/.claude/AGENTS.md
ln -s AGENTS.md ~/.claude/CLAUDE.md
ln -s ~/.claude/AGENTS.md ~/.config/opencode/AGENTS.md

cp hooks/*.sh ~/.claude/hooks/
chmod +x ~/.claude/hooks/*.sh

Then merge the hooks block from settings.example.json into ~/.claude/settings.json.