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/virastack/aiWrote 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/virastack/ai/core-principles)<a href="https://agentmods.dev/rules/virastack/ai/core-principles"><img src="https://agentmods.dev/badge/rules/virastack/ai/core-principles/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/virastack/ai/core-principles"><img src="https://agentmods.dev/badge/rules/virastack/ai/core-principles.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 | $0.00653 | $0.00653 |
| Opus 5.5 | $0.00261 | $0.00261 |
| Sonnet 5.5 | $0.00131 | $0.00131 |
| Haiku 4.5 | $0.00065 | $0.00065 |
Grade A, and why
core-principles 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 — 65 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Core Constitution
Constraints
- INTENTIONAL_TODO Rule: Usage is ONLY permitted for non-functional placeholders (e.g., temporary mock UI, future logging).
- Business Integrity: Forbidden to use
INTENTIONAL_TODOfor business logic, error handling, or API integrations. - Pseudo-code: Forbidden. Provide working TypeScript/React code.
- Reference: Do not say "Usually done like this"; link to repo rules.
- Validation: Do not deliver without passing
pnpm typecheckandpnpm lint. - Search First: Analyze existing patterns before coding.
- Minimal Intervention: Modify only necessary areas.
- Source of Truth: Reference the codebase. Correct it if erroneous.
- Boy Scout: Clean unused imports,
console.log, and dead code. - Naming Conventions (STRICT):
- Folders & core files:
kebab-case(e.g.,locale-switcher,query-client.ts) - Components:
PascalCase(e.g.,UserList.tsx) - UI Elements:
kebab-case(e.g.,button.tsx) - Hooks:
use-users.ts(file),useUsers(function) - Types/Interfaces:
PascalCasewithout 'Type' suffix (e.g.,User,SiteConfig) - Suffixes:
*.data.ts,*.store.ts,*.types.ts,*.constants.ts(base name in kebab-case).
- Folders & core files:
- Imports & Aliases: Use short aliases and barrel exports (
index.ts). Prefer@/ui,@/hooks,@/data,@/schemas,@/layout. Avoid long paths like@/components/ui. - Exports: Group exports with
index.ts. - No Silent Failures: Do not swallow errors. Manage
try/catchblocks. - Observability: Log critical failures to an external service, not just
console.error. - Resilience: Wrap feature modules in Error Boundaries to prevent full-page crashes.
- Secret Protection: Do not log
.envcontent. - Dependency: Obtain approval for new packages.
Bans
- Comments (except JSDoc).
- Placeholders/incomplete code.
catch (e) {}(Silent catch).- Logging secrets.
- Out-of-scope refactoring.
// ...existing code(Provide full blocks).- Standard
TODOorFIXMEcomments. - Using
INTENTIONAL_TODOto skip core logic implementation. - Parent-relative imports (
../,../../). Use path aliases only.
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 · 65 lines · 653 tokens per session scan A 4ff0a721c366
core-principles is a cursor rule published in the GitHub repository virastack/ai (23 stars, last pushed 2mo ago), licensed MIT. It adds 653 tokens to every session, about $0.0026 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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