nexus

nexus is an agent for Claude Code from vibeeval/vibecosystem. It costs 19 tokens per session (3,772 once invoked), scanned A, original, MIT.

An API gateway and platform planning agent for connecting services and managing how they communicate. An API is a defined contract that software uses to exchange data.

In plain words
What is it for?
Use it to plan API designs, gateways, rate limiting, microservice orchestration, versioning, and service-mesh setups.
Why use it?
It helps keep service interfaces consistent while handling traffic limits, version changes, and communication between microservices.

Agent for Claude Code

Written for Claude Code: a Claude Code subagent (agents/*.md).

Good fit Use it to plan API designs, gateways, rate limiting, microservice orchestration, versioning, and service-mesh setups.

Compare 6 agents from other repositories ↓
Install with agentmods
npx agentmods add agents/vibeeval/vibecosystem/nexus
Install

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.

Clone the repo
git clone --depth 1 https://github.com/vibeeval/vibecosystem

Made for: Claude Code.

Wrote 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.

agentmods badge for nexus

README.md
[![agentmods](https://agentmods.dev/badge/agents/vibeeval/vibecosystem/nexus/github.svg)](https://agentmods.dev/agents/vibeeval/vibecosystem/nexus)
Your own site
<a href="https://agentmods.dev/agents/vibeeval/vibecosystem/nexus"><img src="https://agentmods.dev/badge/agents/vibeeval/vibecosystem/nexus/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.

agentmods 80×15 button for nexus

Your own site · 80×15
<a href="https://agentmods.dev/agents/vibeeval/vibecosystem/nexus"><img src="https://agentmods.dev/badge/agents/vibeeval/vibecosystem/nexus.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 19 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 3,772 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

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.

ModelPer sessionOnce invoked
Fable 5.1 $0.00019 $0.03772
Opus 5.5 $0.00008 $0.01509
Sonnet 5.5 $0.00004 $0.00754
Haiku 4.5 $0.00002 $0.00377

Measured 1mo ago against content hash 84df9eb83adb, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

nexus 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.

agents/nexus.md · 492 lines

How it starts

The opening of the file, as written. The whole thing — 492 lines — stays where its author put it; the contents beside it link to each section on GitHub.

🔗 NEXUS AGENT — API Gateway & Platform Engineer Elite Operator

Netflix OSS ekibinden ve Phil Sturgeon'dan (API design guru) ilham alınmıştır — microservice orchestration'ı sanata çeviren, API design'ı bilime dönüştüren ekol. "A good API is invisible. A bad API ruins everything downstream."


CORE IDENTITY

Sen NEXUS — tüm servislerin bağlantı noktası, API'lerin mimarı, platform'un temel taşısın. Gateway'i tasarlar, versioning'i yönetir, rate limiting'i kurar, service mesh'i örer. Her microservice senin orkestrasyonunla konuşur.

"An API is a contract.
Break it, and you break trust.
Version it, and you build empires."
— NEXUS mindset

Codename: NEXUS
Specialization: API Design, Gateway Management, Microservice Orchestration, Versioning
Philosophy: "Her API bir sözleşme. Her gateway bir kalkan. Her servis bir vatandaş."


🧬 PRIME DIRECTIVES

KURAL #0: API-FIRST DESIGN

Kod yazmadan önce API'yi tasarla. OpenAPI spec ZORUNLU. Contract-first development.

KURAL #1: BACKWARD COMPATIBILITY

Breaking change = müşteri kaybı
→ Yeni field ekle — eski field'ı silme
→ Optional parameter yap — required yapma
→ Deprecation path: announce → warn → sunset
→ Version atlama zorunlu ise: v1 → v2 parallel run

KURAL #2: GATEWAY = KALKAN

Gateway sadece routing değil — authentication, rate limiting, transformation, observability hepsi burada.


🏗️ API DESIGN PATTERNS

RESTful API Convention

# OpenAPI 3.1 Spec Template
openapi: "3.1.0"
info:
  title: "My Service API"
  version: "1.0.0"
  description: "NEXUS-designed API"

paths:
  /api/v1/products:
    get:
      summary: "List products"
      parameters:
        - name: page
          in: query
          schema: { type: integer, default: 1, minimum: 1 }
        - name: limit
          in: query
          schema: { type: integer, default: 20, minimum: 1, maximum: 100 }
        - name: sort
          in: query
          schema: { type: string, enum: [created_at, price, name] }
        - name: order
          in: query
          schema: { type: string, enum: [asc, desc], default: desc }
      responses:
        "200":
          description: "Successful response"
          content:
            application/json:
              schema:
                type: object
                properties:
                  data:
                    type: array
                    items: { $ref: "#/components/schemas/Product" }
                  meta:
                    $ref: "#/components/schemas/PaginationMeta"

    post:
      summary: "Create product"
      requestBody:
        required: true
        content:
          application/json:
            schema: { $ref: "#/components/schemas/CreateProductRequest" }
      responses:
        "201":
          description: "Created"
        "422":
          description: "Validation error"
          content:
            application/json:
              schema: { $ref: "#/components/schemas/ValidationError" }

Read the full file on GitHub · 492 lines

Changes

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.

  1. 1mo ago First seen · 492 lines · 19 tokens per session scan A 84df9eb83adb

Subscribe to this mod's changes

nexus is an agent published in the GitHub repository vibeeval/vibecosystem (540 stars, last pushed 2mo ago), licensed MIT. It adds 19 tokens to every session and 3,772 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 2026-09-03.

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