Context7 Skill

Pulls up-to-date, version-specific documentation and code examples straight from the source and places them into the prompt — fighting outdated training data and hallucinated APIs.

Install (CLI) — pin the version

Reviewed versions (re-resolve before each project; record in mcp-versions.json at repo root):

• ctx7 CLI: 0.5.9 (npm package ctx7, NOT @upstash/context7-cli — that scope does not exist)
• @upstash/context7-mcp MCP server: 4.0.4

# npm global install (pinned) — CLI package is `ctx7`, not @upstash/context7-cli:
npm install -g ctx7@0.5.9
# verify:
ctx7 --version

# one-off via npx (pinned):
npx -y ctx7@0.5.9 --version

Install (MCP server — Claude Desktop / Cline / Cursor) — pin the version

Add to the MCP client config (e.g. ~/.config/Claude/claude_desktop_config.json or Cline MCP settings):

{ "mcpServers": { "context7": { "command": "npx", "args": ["-y", "@upstash/context7-mcp@4.0.4"] } } }

Security rule (CWE-829): never run npx -y @upstash/context7-mcp unpinned. The reviewed versions above were resolved 2026-09-04 from https://github.com/upstash/context7/releases. Re-resolve before each project and record the result in mcp-versions.json (a repo-root manifest tracking all MCP tool versions). Do not rely on latest.

MCP exposes two tools:

• resolve-library-id — turn a general library name into a Context7-compatible ID
• query-docs — fetch docs for a library ID + question

Usage

# 1. find the library ID
npx ctx7 library "Entity Framework Core" "<specific question>"

# 2. fetch docs
npx ctx7 docs <libraryId> "<specific implementation question>"

Known useful IDs (verify with step 1 — do not rely on memory):

• /vercel/next.js · /tailwindlabs/tailwindcss.com · /mui/material-ui
• /apollographql/apollo-client · /tanstack/query · /facebook/react
• /prisma/prisma · /kodcu/refik (no — use ctx7 library to resolve)
• HotChocolate: ctx7 library "hotchocolate graphql"
• Trigger.dev: ctx7 library "trigger.dev"
• MCP SDK: ctx7 library "@modelcontextprotocol/sdk"

Rules (from Foundrie + this repo)

• Always use Context7 before writing code that depends on a library's current API (EF Core migrations CLI, HotChocolate resolver API, GraphQL Flutter providers, Trigger.dev task syntax, MCP SDK transports).
• Never paste secrets/keys into Context7 queries.
• Before committing package versions, check Context7 + official sources for the current stable + compatibility.
• Record important version-specific findings in the relevant feature spec or context file.
• If Context7 results conflict with a context file, pause → research → update the context file → implement.

Verify

• ctx7 library returns real library IDs; ctx7 docs returns current docs with version info.
• The MCP server shows as connected in the client (tools resolve-library-id, query-docs).