MCP Tools Overview

Nexus provides 13 MCP tools organized into three categories: Documentation, Memory, and Server Registry.

How to Use These Tools

These tools are designed to be used through natural conversation with your AI assistant. You don't need to know the exact tool names or parameters - just describe what you need.

Example Prompts

Documentation lookup:

"How do I set up authentication in Next.js App Router?"

"Show me examples of React Server Components with data fetching"

"What's the correct way to use Drizzle ORM migrations?"

Memory and context:

"Remember that this project uses pnpm and Tailwind CSS"

"What decisions have we made about the database schema?"

"Save this as a lesson learned: always use parameterized queries"

Server discovery:

"I need to connect Claude to my PostgreSQL database - what MCP servers are available?"

"How do I install the GitHub MCP server?"

What Happens Behind the Scenes

When you ask a question like "How do I use React Query?", your AI assistant:

1. Uses resolve-library to find the library ID for React Query
2. Uses query-docs to search the indexed documentation
3. Returns relevant code examples and explanations

You just ask naturally - the tools handle the rest.

---

Documentation Tools

Search and explore indexed library documentation with semantic search.

🔍

resolve-library

Find library IDs for documentation queries. Search by name to get the exact ID.

📚

query-docs

Search indexed documentation using semantic search. Returns relevant code examples.

ℹ️

get-library-info

Get detailed metadata about a library including description and snippet count.

📋

list-libraries

Browse all indexed libraries. Filter by category.

Quick Reference

Tool	Parameters	Description
resolve-library	libraryName, query?	Find library ID by name
query-docs	libraryId, query, limit?, tokens?	Search documentation
get-library-info	libraryId	Get library metadata
list-libraries	category?, limit?	List indexed libraries

Memory Tools

Store and retrieve persistent context across AI sessions.

💾

save-memory

Store project context, decisions, and learnings. Persists across sessions.

🧠

recall-memories

Retrieve relevant memories using semantic search.

📂

get-project-context

Load all stored context for a specific project.

📝

list-memories

Browse stored memories with filtering options.

Quick Reference

Tool	Parameters	Description
save-memory	title, content, type, project?, tags?, importance?	Store a memory
recall-memories	query, project?, type?, tags?, limit?	Search memories
get-project-context	project, includeTypes?, limit?	Get all project context
list-memories	project?, type?, limit?, offset?	Browse memories
update-memory	memoryId, title?, content?, tags?, importance?	Update a memory
delete-memory	memoryId	Delete a memory

Memory Types

Type	Description	Example
project_context	Architecture, tech stack, conventions	"Next.js 14 with App Router"
session_summary	What was accomplished	"Added authentication flow"
decision	Architectural decisions with rationale	"Chose Prisma over Drizzle because..."
correction	Lessons learned, things to avoid	"Don't use library X, it has issue Y"

Server Registry Tools

Discover and configure MCP servers for additional AI capabilities.

🔎

discover-servers

Find MCP servers by capability, category, or name.

📦

get-server-info

Get detailed documentation about an MCP server.

⚙️

get-server-config

Generate ready-to-use installation configs.

Quick Reference

Tool	Parameters	Description
discover-servers	query?, category?, capabilities?, official?, limit?	Search servers
get-server-info	serverId	Get server documentation
get-server-config	serverId, format?	Generate config

Server Categories

• database - PostgreSQL, SQLite, MongoDB, etc.
• filesystem - File operations, directory access
• devtools - Git, GitHub, build tools
• ai - AI/ML integrations
• cloud - AWS, GCP, Azure services
• productivity - Slack, Notion, Linear, etc.

Authentication

Authentication Required

Memory tools (`save-memory`, `update-memory`, `delete-memory`) require authentication. Use the CLI to authenticate:

nexus auth login

Documentation and server registry tools work without authentication.

Rate Limits

Plan	Requests/minute	Requests/day
Free	20	1,000
Pro	100	10,000
Enterprise	Unlimited	Unlimited

Next Steps

• resolve-library - Start searching documentation
• save-memory - Set up persistent memory
• discover-servers - Find MCP servers