Reletter — Claude Code MCP server: search 7M+ newsletters
A remote MCP server that hands your agent a database of 7M+ email newsletters on Substack, LinkedIn, Ghost, Beehiiv and Kit.
claude mcp add --transport http reletter https://mcp.reletter.comWhat Reletter does
Point the agent at https://mcp.reletter.com and it gets eleven tools. Full-text search runs across issue bodies. Other tools return publication metadata with subscriber counts and engagement, author contacts, recent issues, and chart data. One tool reports your monthly request quota.
Everything goes through the Reletter API, so a key is required. You can grab one from the developer page, or let an autonomous agent provision its own: POST https://api.reletter.com/api/payments/buy/ answers with a 402 challenge, payment goes through a Stripe Shared Payment Token or USDC on Tempo, and the response carries a key tied to a new account. Bundle tiers come from GET https://api.reletter.com/api/payments/bundles/.
No key, no server. Set up the account first. After that, Claude, Codex and Gemini CLI each take a single command, while Cursor and GitHub Copilot want a JSON block in their config.
What it helps with
- pull a full newsletter issue body into the agent context
- find newsletters by topic, platform or audience size
- build a pitch list with verified author emails
- watch for brand or competitor mentions across newsletters
- check current chart positions on Substack, LinkedIn and Kit
Example prompts for the agent
- Find fintech newsletters on Substack with more than 10k subscribers
- Pull the full text of the latest issue from that newsletter
- Collect the author emails for this list of publications
How to install Reletter
Platform CLI: remote server
claude mcp add --transport http reletter https://mcp.reletter.comPlatform CLI: remote server
codex mcp add reletter --url https://mcp.reletter.comConfig file
{
"mcpServers": {
"reletter": {
"url": "https://mcp.reletter.com"
}
}
}Config file
{
"servers": {
"reletter": {
"type": "http",
"url": "https://mcp.reletter.com"
}
}
}Platform CLI: remote server
gemini mcp add -t http reletter https://mcp.reletter.comStep 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 Reletter
How do I install Reletter in Claude Code?
Run claude mcp add --transport http reletter https://mcp.reletter.com, then enter your Reletter API key when the server asks for it.
What does Reletter do?
It connects your agent to a newsletter database: issue search, publication metadata, contacts, chart rankings and quota information.
What do I need before using Reletter?
A Reletter API key, available from the developer page. Autonomous agents can provision one through the Machine Payments Protocol, paying with Stripe or USDC on Tempo.
