Seedfast MCP Server

Seedfast fills a PostgreSQL database with realistic, relationally valid test data generated from its live schema, so a team that cannot put production data into development still gets an environment that behaves like production.

This repository is the public integration surface for its MCP server. You will find the client configuration, the tool reference and a smoke test here. The engine and the CLI themselves are closed-source and ship through npm and Homebrew.

Published in the official MCP registry as st.seedfa/seedfast.

Install

Nothing separate to install. The MCP server is built into the Seedfast CLI and runs straight from npx:

{
  "mcpServers": {
    "seedfast": {
      "command": "npx",
      "args": ["-y", "seedfast@latest", "mcp"],
      "env": {
        "SEEDFAST_API_KEY": "sfk_live_your_api_key_here"
      }
    }
  }
}

That block goes into claude_desktop_config.json for Claude Desktop, .cursor/mcp.json for Cursor, or the equivalent file for VS Code and Claude Code. Client-by-client paths are in the MCP setup guide.

Prefer a local binary? Install the CLI and point command at seedfast with args: ["mcp"] instead:

brew install seedfast-ai/tap/seedfast   # macOS, Linux
npm install -g seedfast                 # any platform with Node.js

Configuration

Variable	Required	What it does
SEEDFAST_API_KEY	yes	API key created in the Seedfast dashboard
SEEDFAST_MCP_RUNS_DB	no	Path to a SQLite file. Without it, runs and plans live in memory and disappear when the server exits

Tools

Thirteen tools cover the whole loop of planning a seed, running it and inspecting what happened.

Tool	What it does
seedfast_doctor	Checks CLI health and whether authentication is configured
seedfast_connections_test	Tests a database connection before anything is written
seedfast_schema_info	Reads the live schema of the target database
seedfast_plan	Builds a seeding plan from a scope description
seedfast_run	Executes a seeding run
seedfast_run_status	Polls a run in progress
seedfast_run_cancel	Aborts a run
seedfast_run_answer	Answers a question the run raised while it was waiting for input
seedfast_plans_list	Lists saved plans
seedfast_plan_get	Reads one saved plan
seedfast_plan_create	Saves a new plan
seedfast_plan_update	Edits a saved plan
seedfast_plan_delete	Removes a saved plan

Resources

URI	Media type	Contents
seedfast://runs/{runId}/summary	application/json	Summary of a seeding run
seedfast://runs/{runId}/log	application/x-ndjson	Event log of a seeding run
seedfast://runs/{runId}/pending_question	application/json	The question a run is waiting on, while it is in awaiting_input
seedfast://plans/{planId}	application/json	Details of a saved plan

Prompts

Two prompts ship with the server: seed-production-db, which takes a scope and a description of the target database, and scope-examples, which turns a use case into example scopes.

Verify

The smoke test starts the published package over stdio, completes an MCP handshake and lists the tools. It needs no API key, since it never reaches the backend:

node scripts/smoke-test.mjs

Expected output ends with the protocol version the server negotiated and the number of tools it advertises.

Databases

Seedfast works with PostgreSQL today. Going PostgreSQL-first was deliberate, since its constraint and relationship system is the richest one out there and that is exactly where generating believable data gets hard. Support for MySQL, Oracle and SQLite is in development.

Links

• Documentation
• MCP setup guide
• npm package
• Questions and bug reports: support@seedfa.st

License

MIT for the contents of this repository. The Seedfast CLI is distributed under the same license; its engine runs as a hosted service.