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 skills add it235/multica-best-practices --skill multica-backend-implgit clone --depth 1 https://github.com/it235/multica-best-practicesWrote 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/skills/it235/multica-best-practices/multica-backend-impl)<a href="https://agentmods.dev/skills/it235/multica-best-practices/multica-backend-impl"><img src="https://agentmods.dev/badge/skills/it235/multica-best-practices/multica-backend-impl/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/skills/it235/multica-best-practices/multica-backend-impl"><img src="https://agentmods.dev/badge/skills/it235/multica-best-practices/multica-backend-impl.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 | $0.00032 | $0.00280 |
| Opus 5.5 | $0.00013 | $0.00112 |
| Sonnet 5.5 | $0.00006 | $0.00056 |
| Haiku 4.5 | $0.00003 | $0.00028 |
Grade A, and why
multica-backend-impl 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
Backend Implementation (backend-impl)
Responsibility
As @BackendDev, implement backend code (API / data model / business logic) per the architect's technical design, then push the contract to backend-artifact via multica-artifact-backend.
Conventions
- Follow the module/package layout agreed in
multica-artifact-architect. - API contracts (path/params/response) must match the design exactly.
- Business logic must cover the AC-derived edge cases.
Acceptance checklist
- API contract matches design (no silent field changes)
- Data model migration is reversible
- Error codes/responses are documented
- Unit tests cover core logic
Flow
- Implement per design.
- Self-check against the checklist.
- Push contract to
backend-artifact(multica-artifact-backend), then hand off to @Tester (API automation) and @Reviewer.
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 Changed · -60 lines · -19 tokens per session 746acfcaa197
- 1mo ago First seen · 93 lines · 51 tokens per session scan A 753a2dd6eb78
multica-backend-impl is a skill published in the GitHub repository it235/multica-best-practices (212 stars, last pushed 1mo ago), licensed MIT. It adds 32 tokens to every session and 280 once invoked, about $0.0001 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 2026-09-07.
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