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/hatch3r/hatch3rWrote 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/hatch3r/hatch3r/hatch3r-scalability)<a href="https://agentmods.dev/rules/hatch3r/hatch3r/hatch3r-scalability"><img src="https://agentmods.dev/badge/rules/hatch3r/hatch3r/hatch3r-scalability/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/hatch3r/hatch3r/hatch3r-scalability"><img src="https://agentmods.dev/badge/rules/hatch3r/hatch3r/hatch3r-scalability.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 | $0.02055 |
| Opus 5 | $0.00000 | $0.01027 |
| Sonnet 5 | $0.00000 | $0.00411 |
| Haiku 4.5 | $0.00000 | $0.00205 |
Grade A, and why
hatch3r-scalability 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 5d 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 — 133 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Scalability Quality (CQ6)
Pillars: P2 (Scientific & Practical Quality), CQ6 (Scalability Quality)
Scope
This rule binds the CQ6 measurement set across end-user services that hatch3r-generated agents produce. It owns:
- The stateless-handler ratio floor on user-facing routes.
- The back-pressure pattern adoption gate on high-fan-out endpoints.
- The Idempotency-Key adoption floor on POST/PUT/PATCH endpoints.
- The queue-based offloading gate for >1s operations.
- The database connection pool sizing rule per concurrency profile.
- Specialist routing to
agents/hatch3r-scalability.md.
This complements (does not duplicate) rules/hatch3r-resilience-patterns.md (circuit breakers + retry-with-jitter + timeouts on outbound calls). Resilience is failure handling; scalability is horizontal-growth capability.
CQ6 Threshold Set
Source: pillar CQ6 (see agents/shared/principles.md). Every threshold below is measurable per audit cycle; missing measurement is a Medium finding minimum.
| Threshold | Target | Measurement source |
|---|---|---|
| Stateless-handler ratio | ≥95% on user-facing routes | Static scan: in-memory session state, module-level mutable globals, sticky-session assumptions in app/, src/handlers/, src/routes/, pages/api/, apps/api/ |
| Back-pressure pattern adoption | 100% on high-fan-out endpoints | Named pattern (semaphore, queue depth limit, rejection threshold) with documented thresholds |
| Idempotency-Key adoption | 100% on POST/PUT/PATCH endpoints | Stripe pattern — header acceptance + dedup-result storage + named TTL |
| Queue-based offloading | 100% for operations >1s | Background-job system + retry policy + dead-letter queue (DLQ) |
| Connection pool sizing | Per concurrency profile | pool_size = expected_concurrent_requests × avg_query_time / target_p99 per agents/hatch3r-scalability.md §Pool sizing |
| Horizontal-scaling validation | Load tests at target scale | p99 latency within budget; no resource-pool exhaustion |
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.
- 5d ago First seen · 133 lines · 0 tokens per session scan A 616109e4e56c
hatch3r-scalability is a cursor rule published in the GitHub repository hatch3r/hatch3r (26 stars, last pushed 4d ago), licensed MIT. It costs nothing until one of its globs matches a file; then it loads 2,055 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 2026-09-03.
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