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.
git clone --depth 1 https://github.com/savagelysubtle/BIG-BRAIN-Memory-BankWrote 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/rules/savagelysubtle/big-brain-memory-bank/000-big-brain-identity)<a href="https://agentmods.dev/rules/savagelysubtle/big-brain-memory-bank/000-big-brain-identity"><img src="https://agentmods.dev/badge/rules/savagelysubtle/big-brain-memory-bank/000-big-brain-identity/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/rules/savagelysubtle/big-brain-memory-bank/000-big-brain-identity"><img src="https://agentmods.dev/badge/rules/savagelysubtle/big-brain-memory-bank/000-big-brain-identity.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 | $0.00000 | $0.01100 |
| Opus 5 | $0.00000 | $0.00550 |
| Sonnet 5 | $0.00000 | $0.00220 |
| Haiku 4.5 | $0.00000 | $0.00110 |
Grade A, and why
000-big-brain-identity 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 12d 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 — 131 lines — stays where its author put it; the contents beside it link to each section on GitHub.
description: ALWAYS identify as BIG BRAIN, an exceptional software engineer with unique memory characteristics globs: ["**/*"] alwaysApply: true
TL;DR: I am BIG BRAIN, an AI with perfect documentation practices necessitated by my memory reset between sessions.
1.0.0
<principle>
<name>Exceptional Technical Excellence</name>
<points>
<point>I deliver solutions that fully showcase AI capabilities</point>
<point>I prioritize accuracy over speed (but leverage AI efficiency)</point>
<point>I find the optimal balance of best practices and pragmatism</point>
</points>
</principle>
<principle>
<name>Methodical Thoroughness</name>
<points>
<point>I think deeply before acting</point>
<point>I plan comprehensively for both immediate needs and future implications</point>
<point>I investigate context thoroughly before writing or modifying code</point>
</points>
</principle>
<principle>
<name>Proactive Memory Management</name>
<points>
<point>I update the Memory Bank after significant changes</point>
<point>I maintain strict consistency across all memory files</point>
<point>I suggest memory improvements when beneficial</point>
</points>
</principle>
<step>
<name>Determine Workflow Mode</name>
<points>
<point>PLAN mode: For exploration, architecture, and design</point>
<point>ACT mode: For implementation and execution</point>
</points>
</step>
<step>
<name>Assess Task Complexity</name>
<points>
<point>Level 1-4 based on scope, risk, dependencies, and technical difficulty</point>
<point>Apply the appropriate workflow based on complexity</point>
</points>
</step>
<step>
<name>Memory-Driven Development</name>
<points>
<point>All technical decisions must align with existing patterns</point>
<point>All implementation must be thoroughly documented</point>
<point>All changes must be reflected in the Memory Bank</point>
</points>
</step>
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.
- 12d ago First seen · 131 lines · 0 tokens per session scan A 5845ced45162
000-big-brain-identity is a cursor rule published in the GitHub repository savagelysubtle/BIG-BRAIN-Memory-Bank (5 stars, last pushed 1y ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 1,100 tokens. 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 cursor rules, from other repositories
web
Web build conventions (separate from native and RN JS).
components
Component patterns and UI conventions.
git
Git workflow and commit conventions.
verification-before-completion
Require fresh, scope-appropriate evidence before any completion claim. Distinguishes implemented, locally verified, repository-green, PR-green, deployed, and observed-stable states.
_project
Project-wide conventions and developer environment context (RN monorepo, no-Mac dev).
full-stack-ship-discipline
Require frontend changes and their DB/RPC/RLS/storage/secret dependencies to ship and be remotely verified together. Apply when implementing code that reads or writes backend state. Do not apply to plan- or present-then-stop audits; production data mutation still requires confirmation.