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/aiagentwithdhruv/ai-dev-stackWrote 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/aiagentwithdhruv/ai-dev-stack/45-environment-config)<a href="https://agentmods.dev/rules/aiagentwithdhruv/ai-dev-stack/45-environment-config"><img src="https://agentmods.dev/badge/rules/aiagentwithdhruv/ai-dev-stack/45-environment-config/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/aiagentwithdhruv/ai-dev-stack/45-environment-config"><img src="https://agentmods.dev/badge/rules/aiagentwithdhruv/ai-dev-stack/45-environment-config.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 | $0.00302 | $0.00302 |
| Opus 5.5 | $0.00121 | $0.00121 |
| Sonnet 5.5 | $0.00060 | $0.00060 |
| Haiku 4.5 | $0.00030 | $0.00030 |
Grade A, and why
45-environment-config 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.
What it actually says
Configuration rules:
- All environment-specific values must come from environment variables or config files.
- Use a single config module/service that validates all required env vars at startup.
- Fail fast on missing or invalid configuration — do not silently use defaults for critical values.
- Maintain .env.example with every required variable documented (no real values).
Environment parity:
- dev, staging, and production must use the same config structure.
- Environment-specific behavior must be controlled by explicit flags, not implicit detection.
- Database URLs, API keys, model endpoints, and feature flags must all be configurable per environment.
Secrets management:
- Never commit .env, credentials.json, token.json, or any file with real secrets.
- Use .gitignore to block secret files.
- In production, prefer secret managers (AWS Secrets Manager, Vercel env vars, VPS env files) over baked-in values.
- Rotate secrets on a schedule or after any exposure.
Validation expectations:
- Validate config at application startup, not at first use.
- Type-check config values (ports as int, URLs as valid URLs, booleans as bool).
- Log which config keys are loaded (never log values) for debugging.
Do not:
- Hardcode API keys, tokens, passwords, or URLs anywhere in source code.
- Use different config loading patterns across services in the same project.
- Commit .env files or any file listed in .gitignore.
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 · 32 lines · 302 tokens per session scan A 16ba9e93c9af
45-environment-config is a cursor rule published in the GitHub repository aiagentwithdhruv/ai-dev-stack (11 stars, last pushed 3mo ago), licensed MIT. It adds 302 tokens to every session, about $0.0012 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 2026-08-31.
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