LastSearch — Claude Code MCP server: what it does, how to install
Connects AI agents to live web search, returning verified claims with source citations and confidence scores. Useful when factual accuracy matters.
claude mcp add lastsearch -e LASTSEARCH_API_KEY=<LASTSEARCH_API_KEY> -- npx -y lastsearchWhat LastSearch does
This server runs live web searches and extracts text directly from target pages. Compound statements are broken into verifiable single claims. Each claim gets a confidence score between 0 and 1. Scores derive from evidence rather than LLM self-evaluations.
Depth modes range from fast searches to a multi-iteration deep cycle running up to 4 steps. The server also manages research sessions with persistent memory. Every tool requires a LASTSEARCH_API_KEY environment variable. Free accounts receive 100 premium queries daily before falling back to simpler matching.
What it helps with
- validate statements against actual page content with direct citations
- decompose compound claims into independently verified facts
- persist research context across multiple queries using dedicated sessions
- contrast unverified LLM answers against evidence gathered from the web
Example prompts for the agent
- Run answer with depth thorough to investigate contradictory findings on dietary caffeine
- Set up a session named quantum-notes using session_create and collect principles of entanglement
- Fetch live details on Falcon 9 launches using search and review the verification scores
How to install LastSearch
Platform CLI
claude mcp add lastsearch -e LASTSEARCH_API_KEY=<LASTSEARCH_API_KEY> -- npx -y lastsearchReplace <…> with your own values
Platform CLI
codex mcp add mcp --env LASTSEARCH_API_KEY=<LASTSEARCH_API_KEY> -- npx -y lastsearchReplace <…> with your own values
Config file
{
"mcpServers": {
"mcp": {
"command": "npx",
"args": [
"-y",
"lastsearch"
],
"env": {
"LASTSEARCH_API_KEY": "<LASTSEARCH_API_KEY>"
}
}
}
}Replace <…> with your own values
Config file
{
"servers": {
"mcp": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"lastsearch"
],
"env": {
"LASTSEARCH_API_KEY": "<LASTSEARCH_API_KEY>"
}
}
}
}Replace <…> with your own values
Platform CLI
gemini mcp add -e LASTSEARCH_API_KEY=<LASTSEARCH_API_KEY> mcp npx -y lastsearchReplace <…> with your own values
Step by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about LastSearch
How do I install LastSearch in Claude Code?
Run claude mcp add lastsearch -e LASTSEARCH_API_KEY=<LASTSEARCH_API_KEY> -- npx -y lastsearch, replacing <LASTSEARCH_API_KEY> with your active key.
What does LastSearch do?
It provides search and extraction tools that verify information against actual web pages, returning citations and empirical confidence scores.
What happens when the daily API quota runs out?
Free accounts get 100 premium queries every 24 hours. Once depleted, verification automatically reverts to basic keyword checks, and deep mode drops to thorough.
