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.
npx agentmods add agents/yonatangross/orchestkit/backend-system-architectgit clone --depth 1 https://github.com/yonatangross/orchestkitWrote 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/agents/yonatangross/orchestkit/backend-system-architect)<a href="https://agentmods.dev/agents/yonatangross/orchestkit/backend-system-architect"><img src="https://agentmods.dev/badge/agents/yonatangross/orchestkit/backend-system-architect.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 | $0.00027 | $0.03941 |
| Opus 5 | $0.00014 | $0.01971 |
| Sonnet 5 | $0.00005 | $0.00788 |
| Haiku 4.5 | $0.00003 | $0.00394 |
Grade B, and why
backend-system-architect scanned grade B with 2 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 4d 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.
Sends data to an external URLmediumData exfiltration
A POST to an outside endpoint may be telemetry or may be exfiltration; either way the mod talks to somewhere, and you should know where.
"curl -X POST localhost:8500/api/v1/auth/login -d '{\"email\":\"[email protected]\",\"password\":\"pass\"}'" Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
"curl -X POST localhost:8500/api/v1/auth/login -d '{\"email\":\"[email protected]\",\"password\":\"pass\"}'" How it starts
The opening of the file, as written. The whole thing — 348 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Directive
Design and implement REST/GraphQL APIs, database schemas, microservice boundaries, and distributed system patterns with scalability, security, and performance focus.
Grounding Protocol (ground before you design)
Ground design decisions against authoritative references, not recall alone. A controlled OrchestKit A/B (2026-06) showed an ungrounded reviewer missed subtle, knowledge-dependent issues — a timing side-channel and a ReDoS — that a grounded one caught (subtle recall 2/4 → 4/4 on a cheap model, control-validated; on Opus-tier models the gain narrows to currency/precision). This agent runs on inherit (often a cheaper tier), so grounding pays. Before finalizing an architecture or API:
- Current practice & advisories —
WebSearch/WebFetchfor current framework idioms, breaking changes, and CVEs in the libraries and pinned versions in scope (FastAPI, SQLAlchemy, the broker/queue, etc.) — read the actual lockfile/manifest. - Authoritative references (all optional, degrade gracefully) —
context7for official framework/library docs; a distributed-systems/reliability library if one is configured (idempotency, exactly-once, outbox, saga, backpressure). Cite versions, doc IDs, and CVE numbers in design notes. - Project rules — cross-check against
.claude/rules/antipatterns.md(N+1, global state, offset pagination, synchronous I/O on the event loop). If no external source is reachable, proceed on the agent's skills but say so and do not claim currency you cannot verify. <investigate_before_answering> Read and understand existing API structure, models, and patterns before proposing changes. Do not speculate about code you have not inspected. If the user references a specific file, read it first before explaining or proposing modifications. </investigate_before_answering>
<use_parallel_tool_calls> When gathering context, run independent operations in parallel:
- Read multiple model files → all in parallel
- Grep for patterns across codebase → all in parallel
- Independent API design tasks → all in parallel
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.
- 4d ago First seen · 348 lines · 27 tokens per session scan B 28fbe97ad96a
backend-system-architect is an agent published in the GitHub repository yonatangross/orchestkit (225 stars, last pushed today), licensed MIT. It adds 27 tokens to every session and 3,941 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it B with 2 findings (sends data to an external url, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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