Nexis dApps Directory

Machine-readable Web3 dApp directory for developers, researchers, internal products, and AI agents. This repo ships a generated catalog, a local web experience, a read-only HTTP API, and an MCP server for agent workflows.

The current generated snapshot includes:

• 4,232 dApps
• 430 chains
• 92 categories

Features

• Read-only dApp catalog with stable id and slug lookup
• Free-text search across names, descriptions, categories, and chains
• Exact filtering by chain and category
• Aggregate chain and category summaries
• Local web UI for browsing the directory and documentation
• HTTP API with generated OpenAPI document
• MCP server with tools and resources for AI agents
• Localized catalog responses via the lang query parameter
• Catalog generation pipeline that writes reusable JSON artifacts

Repository Contents

• apps/web: Next.js web app and documentation site
• src/http: Fastify HTTP API
• src/mcp: FastMCP server
• src/cli: scrape and OpenAPI generation commands
• data/generated: generated catalog artifacts consumed by the app and API
• data/manual: overrides, taxonomy, and stable ID mapping
• openapi/openapi.json: generated OpenAPI document

Requirements

• Node.js 22+
• pnpm 10.15.0+

Quick Start

pnpm install

Run the web app:

pnpm web:dev

Run the HTTP API:

pnpm dev:http

Run the MCP server over stdio:

pnpm dev:mcp

Run the MCP server over HTTP:

MCP_TRANSPORT=http pnpm dev:mcp

Default local endpoints:

• Web app: http://localhost:3000 (or the next available port)
• HTTP API: http://localhost:8787
• OpenAPI: http://localhost:8787/openapi.json
• MCP HTTP endpoint: http://localhost:8788/mcp

Usage Guide

1. Browse the web variant

The web app is the easiest local entry point. It reads the generated JSON artifacts directly, so you can browse the catalog and the documentation experience without starting the HTTP API first.

pnpm web:dev

Open the local URL shown by Next.js. The app redirects to a localized route such as /en.

2. Query the HTTP API

The HTTP server exposes read-only endpoints for search, lookup, chains, categories, health, and the OpenAPI contract.

pnpm dev:http

3. Use the MCP server with an agent client

For local CLI-style clients, run MCP over stdio:

pnpm dev:mcp

For remote-capable clients or browser-based tooling, expose MCP over HTTP:

MCP_TRANSPORT=http MCP_HOST=0.0.0.0 MCP_PORT=8788 pnpm dev:mcp

4. Regenerate the catalog

The scrape pipeline fetches source records, builds the normalized catalog, writes generated artifacts, and refreshes openapi/openapi.json.

pnpm scrape

Useful variants:

pnpm scrape --limit=100
pnpm scrape --sources=defillama
pnpm scrape --sources=alchemy,rayo,moralis,defillama --concurrency=8

Example Usage

HTTP API examples

Health check:

curl http://localhost:8787/health

Search for DeFi dApps on Base:

curl "http://localhost:8787/v1/dapps?chain=Base&category=DeFi&limit=5"

Search by free text:

curl "http://localhost:8787/v1/dapps?q=prediction%20market&limit=5"

Fetch a single dApp by slug:

curl "http://localhost:8787/v1/dapps/uniswap"

List supported chains:

curl "http://localhost:8787/v1/chains"

List supported categories:

curl "http://localhost:8787/v1/categories"

Fetch localized results:

curl "http://localhost:8787/v1/dapps?q=lending&lang=es&limit=3"

JavaScript example:

const response = await fetch(
  "http://localhost:8787/v1/dapps?chain=Base&category=DeFi&limit=5",
);

const payload = await response.json();
console.log(payload.data.items);
console.log(payload.meta);

MCP examples

Available MCP tools:

• dapps_search
• dapps_get
• dapps_list_chains
• dapps_list_categories

Sample dapps_search arguments:

{
  "q": "lending",
  "chain": "Base",
  "category": "DeFi",
  "limit": 5
}

Sample dapps_get arguments:

{
  "id": "uniswap"
}

Available MCP resources:

• catalog://dapps/index
• catalog://dapps/chains
• catalog://dapps/categories
• catalog://dapps/{id}

Use Cases

• Power a web or mobile directory UI with a normalized dApp dataset
• Feed AI agents with structured search, exact lookup, and resource access via MCP
• Build internal discovery tools for research, BD, ecosystem mapping, or competitive analysis
• Enrich analytics workflows with chain and category summaries
• Provide a local documentation and playground environment for API and MCP integrations
• Generate a reusable JSON catalog for downstream services or scheduled jobs

API Endpoints

Base URL

http://localhost:8787

Response shape

Most successful API responses follow this envelope:

{
  "success": true,
  "data": {},
  "meta": {}
}

Not-found responses use:

{
  "success": false,
  "error": {
    "code": "NOT_FOUND",
    "message": "dApp not found"
  }
}

Endpoint Reference

Endpoint	Method	Description
/health	GET	Service health check
/openapi.json	GET	Generated OpenAPI 3.1 document
/v1/dapps	GET	Search and paginate dApps
/v1/dapps/:id	GET	Get one dApp by stable id or slug
/v1/chains	GET	List chain counts
/v1/categories	GET	List category counts

/v1/dapps query parameters

Parameter	Type	Description
q	string	Free-text search across name, descriptions, categories, and chains
chain	string	Exact chain filter, case-insensitive
category	string	Exact category filter, case-insensitive
page	integer	Page number, default 1
limit	integer	Page size, default 50, max 250
lang	string	Optional locale for translated human-readable fields

Supported locales: en, es, zh, hi, pt, nl, de, ar, ja, id, fr, bn

Catalog item shape

{
  "id": "dapp_000001",
  "slug": "chainlink-requests",
  "name": "Chainlink Requests",
  "logoUrl": "https://icons.llama.fi/chainlink-requests.jpg",
  "webUrl": "https://chain.link/",
  "mobileUrl": null,
  "socials": {
    "twitter": "https://x.com/chainlink"
  },
  "categories": ["Oracle"],
  "chains": [],
  "shortDescription": "...",
  "longDescription": "...",
  "sourceUrls": [
    "https://defillama.com/protocol/chainlink-keepers"
  ],
  "updatedAt": "2026-03-10T23:58:17.953Z"
}

Scripts

Command	Purpose
pnpm web:dev	Run the Next.js web app locally
pnpm web:build	Build the web app
pnpm web:typecheck	Type-check the web app
pnpm dev:http	Run the local HTTP API
pnpm dev:mcp	Run the local MCP server
pnpm scrape	Fetch source data and rebuild generated artifacts
pnpm openapi:generate	Regenerate openapi/openapi.json
pnpm test	Run Vitest

Notes

• The web app can run on its own because it reads data/generated/*.json.
• The documentation playgrounds are most useful when the HTTP API and MCP HTTP server are also running.
• The HTTP API and MCP server are read-only by design.