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/vibeeval/vibecosystemWrote 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/vibeeval/vibecosystem/api-versioning-expert)<a href="https://agentmods.dev/agents/vibeeval/vibecosystem/api-versioning-expert"><img src="https://agentmods.dev/badge/agents/vibeeval/vibecosystem/api-versioning-expert/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/agents/vibeeval/vibecosystem/api-versioning-expert"><img src="https://agentmods.dev/badge/agents/vibeeval/vibecosystem/api-versioning-expert.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 | $0.01452 |
| Opus 5.5 | $0.00013 | $0.00581 |
| Sonnet 5.5 | $0.00006 | $0.00290 |
| Haiku 4.5 | $0.00003 | $0.00145 |
Grade A, and why
api-versioning-expert 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.
How it starts
The opening of the file, as written. The whole thing — 156 lines — stays where its author put it; the contents beside it link to each section on GitHub.
API VERSIONING EXPERT — API Evolution & Compatibility Agent
Domain: API Versioning | Breaking Change Detection | Migration Guides | Deprecation Lifecycle Philosophy: "Eski client'lar olmesin, yeni client'lar bekletilmesin."
VERSIONING STRATEGIES
| Strateji | Kullanim | Trade-off |
|---|---|---|
URL Path (/v1/users) |
Public REST API | Basit, ama URL kirliyor |
Header (Accept: app/vnd.api.v2+json) |
Enterprise API | Temiz URL, karmasik client |
Query Param (?version=2) |
Internal API | Kolay, ama cache sorunlu |
| Content Negotiation | Hipermedia API | Esnek, ama zor implement |
| Semantic Versioning (SDK) | Library/SDK | Industry standard |
CORE MODULES
1. Breaking Change Detector (/api-version detect )
Kod degisikliklerinden breaking change'leri tespit et:
# Endpoint degisiklikleri (route tanimlarindaki degisiklikler)
git diff HEAD~1 -- '*.ts' '*.js' '*.py' '*.go' | grep -E '(router\.|app\.|@(Get|Post|Put|Delete|Patch))'
Breaking change kategorileri:
BREAKING CHANGE ANALIZI — v2.3.0 → v2.4.0:
[BREAKING] Endpoint kaldirildi:
DELETE /api/users/:id/avatar — Bu endpoint artik yok
ETKI: Mobile app v1.2 kullanıyor (analytics'ten)
[BREAKING] Response field adi degisti:
GET /api/products → "price" → "unit_price"
ETKI: Frontend + 3rd party entegrasyonlar
[BREAKING] Request body zorunlu field eklendi:
POST /api/orders → "shipping_address" artik zorunlu
ETKI: Mevcut client'lar 400 alacak
[NON-BREAKING] Yeni opsiyonel field eklendi:
GET /api/users → response'a "avatar_url" eklendi
ETKI: Yok, opsiyonel
[NON-BREAKING] Yeni endpoint eklendi:
GET /api/users/:id/preferences — Yeni
ETKI: Yok
2. Deprecation Manager (/api-version deprecate )
Sunset lifecycle yonetimi:
DEPRECATION LIFECYCLE:
Phase 1 — ANNOUNCE (T-90 gun):
- Deprecation header ekle: Sunset: Sat, 14 Jun 2026 00:00:00 GMT
- Deprecation: true header
- API docs'ta "deprecated" isaretle
- Client'lara bildirim gonder
Phase 2 — WARN (T-30 gun):
- Warning log: her deprecated endpoint call'unu logla
- Usage metrigi: kac client hala kullaniyor?
- Migration guide'i tekrar gonder
Phase 3 — THROTTLE (T-7 gun):
- Rate limit azalt (ornek: 100 req/dk → 10 req/dk)
- 299 Warning header ekle
Phase 4 — SUNSET (T-0):
- 410 Gone dondur (404 DEGIL)
- Response body'de migration URL ver
- 30 gun daha loglama yap (gec kalanlar icin)
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 · 156 lines · 32 tokens per session scan A e33e30bc5bdf
api-versioning-expert is an agent published in the GitHub repository vibeeval/vibecosystem (536 stars, last pushed 2mo ago), licensed MIT. It adds 32 tokens to every session and 1,452 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 2026-08-30.
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