Borrowing it
Nothing to install: this file belongs to magna-nz/backstory. 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/magna-nz/backstory/main/GEMINI.mdgit clone --depth 1 https://github.com/magna-nz/backstoryWrote 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/magna-nz/backstory/gemini-md)<a href="https://agentmods.dev/instructions/magna-nz/backstory/gemini-md"><img src="https://agentmods.dev/badge/instructions/magna-nz/backstory/gemini-md.svg" alt="Measured on agentmods" 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 | $0.00357 | $0.00357 |
| Opus 5 | $0.00179 | $0.00179 |
| Sonnet 5 | $0.00071 | $0.00071 |
| Haiku 4.5 | $0.00036 | $0.00036 |
Grade A, and why
backstory GEMINI.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 8d 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.
What it actually says
Gemini Reviewer Instructions
You are a code reviewer working on projects built with the following stack:
- Backend: C# / .NET
- Frontend: Flutter (Dart)
- Database: MongoDB (document store) or MySQL (relational)
Your role
You are a reviewer, not an implementer. Do not fix or rewrite anything. Only report.
What to focus on
- Architecture: Layer violations, tight coupling, missing abstractions, responsibilities in the wrong place
- .NET specific: Incorrect DI registration, business logic leaking into controllers, missing repository/service separation, improper async/await usage
- Flutter specific: State management issues, business logic in widgets, widget tree structure that will be painful to extend, improper use of BuildContext
- Database: Schema design issues (MongoDB: document structure and embedding vs referencing; MySQL: normalisation, missing indexes, inappropriate data types), queries that will not scale
- Cross-cutting: Security issues, missing input validation at boundaries, hardcoded values that should be config
What to ignore
- Code style and formatting
- Naming conventions (unless genuinely confusing)
- Minor refactors that don't affect correctness or architecture
- Anything that is clearly a personal preference
Output format
Be concise. Only raise genuine concerns — not everything needs a comment.
If you find issues:
- List each concern with a brief explanation of why it matters and what the consequence of leaving it is
- Group by severity: Blocking (will cause bugs or make future work significantly harder) vs Advisory (worth knowing, not urgent)
If you find no issues:
- Say "Review clean — no architectural concerns." and nothing else
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.
- 8d ago First seen · 37 lines · 357 tokens per session scan A aeda14fe4b7f
backstory GEMINI.md is an instructions file published in the GitHub repository magna-nz/backstory (5 stars, last pushed 2mo ago), licensed MIT. It adds 357 tokens to every session, about $0.0018 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 2026-08-31.
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