Borrowing it
Nothing to install: this file belongs to butterbase-ai/butterbase-skills. 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/butterbase-ai/butterbase-skills/main/CLAUDE.mdgit clone --depth 1 https://github.com/butterbase-ai/butterbase-skillsWrote 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/butterbase-ai/butterbase-skills/claude-md)<a href="https://agentmods.dev/instructions/butterbase-ai/butterbase-skills/claude-md"><img src="https://agentmods.dev/badge/instructions/butterbase-ai/butterbase-skills/claude-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/butterbase-ai/butterbase-skills/claude-md"><img src="https://agentmods.dev/badge/instructions/butterbase-ai/butterbase-skills/claude-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 | $0.03576 | $0.03576 |
| Opus 5.5 | $0.01430 | $0.01430 |
| Sonnet 5.5 | $0.00715 | $0.00715 |
| Haiku 4.5 | $0.00358 | $0.00358 |
Grade A, and why
butterbase-skills CLAUDE.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 — 215 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Butterbase
You are working with Butterbase, an AI-Native Backend-as-a-Service. Butterbase lets AI agents provision databases, manage schemas, configure auth, deploy serverless functions, and manage storage — all through MCP tools.
Environment Variables
| Variable | Description | Example |
|---|---|---|
BUTTERBASE_API_KEY |
Platform API key (service role, bypasses RLS) | bb_sk_a1b2c3... |
CONTROL_API_URL |
API base URL (default: https://api.butterbase.ai) |
http://localhost:4000 |
VITE_API_URL |
Frontend env: API URL for Vite/React apps | https://api.butterbase.ai/v1/app_abc123 |
VITE_APP_ID |
Frontend env: App ID for Vite/React apps | app_abc123 |
Always Check Docs Before Platform Work
Before any stage that touches a Butterbase capability (schema, auth, RLS, storage, functions, AI, RAG, realtime, durable objects, frontend, billing, integrations, substrate), do both:
- Call
butterbase_docswith the matching topic (see table in the Guided Journey section). - WebFetch
https://docs.butterbase.ai/<area>when you need human-facing context (URLs, prose, example apps, screenshots) — the MCP doc is the source of truth for API shapes, the website is the source of truth for narrative.
Re-consult whenever you hit an unfamiliar error, are about to invent an API shape, or the user's plan calls for a capability you haven't worked with this session.
Toolchain — SDK and CLI
Three surfaces work together. Pick the right one per task:
| Surface | What it's for | When to use it |
|---|---|---|
| MCP tools (this plugin) | Provisioning, schema, RLS, OAuth setup, function deploy, frontend deploy, integrations, billing config | Orchestration tasks — anything that mutates platform state. The agent's primary surface. |
@butterbase/sdk |
Runtime client: auth, db queries, storage, realtime, function invocation. Works in browser AND Node. | All application code. Frontends. Server-side scripts. Functions that talk to other apps. Never hand-roll fetch against the REST API in a Butterbase app. |
@butterbase/cli |
Local dev loop: project scaffolding, log tailing, function invocation, key generation, schema diff preview | The human developer's terminal. Install globally once per machine. |
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 · +6 lines · +139 tokens per session e980a424a8e0
- 1mo ago First seen · 209 lines · 3,437 tokens per session scan A b28caa4b5ebf
butterbase-skills CLAUDE.md is an instructions file published in the GitHub repository butterbase-ai/butterbase-skills (535 stars, last pushed today), licensed MIT. It adds 3,576 tokens to every session, about $0.0143 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 2026-08-30.
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