GraphJin

Name: GraphJin
Author: Spacy

A GraphQL compiler and MCP server that puts databases, files and code indexes behind one governed graph

By Spacy (individual) Go Local · stdio, Streamable HTTP Databases Developer tools

GitHub npm Website

75 popularity score ★ 3.2k ↓ 833/wk

Connect your client

Local (once it is running)

Add in one click

Add to Cursor Add to VS Code Add to LM Studio Add to Goose

Opens the app, which asks before it adds the server.

Or add it by command or config

Claude CodeTerminal

claude mcp add --transport http graphjin http://localhost:8080/api/v1/mcp

Cursor~/.cursor/mcp.json

{
  "mcpServers": {
    "graphjin": {
      "url": "http://localhost:8080/api/v1/mcp"
    }
  }
}

VS Code.vscode/mcp.json

{
  "servers": {
    "graphjin": {
      "type": "http",
      "url": "http://localhost:8080/api/v1/mcp"
    }
  }
}

Codex~/.codex/config.toml

[mcp_servers.graphjin]
url = "http://localhost:8080/api/v1/mcp"

Gemini CLITerminal

gemini mcp add --scope user --transport http graphjin http://localhost:8080/api/v1/mcp

Local (npm)

Add in one click

Add to Cursor Add to VS Code Add to LM Studio

Opens the app, which asks before it adds the server. Then replace each <NAME> in its settings with your value.

Or add it by command or config

FirstTerminal

npm install -g graphjin
graphjin serve new <APP_NAME>

Claude CodeTerminal

claude mcp add graphjin -- graphjin mcp --path '<ABSOLUTE_PATH_TO_APP>'

Claude Desktopclaude_desktop_config.json

{
  "mcpServers": {
    "graphjin": {
      "command": "graphjin",
      "args": [
        "mcp",
        "--path",
        "<ABSOLUTE_PATH_TO_APP>"
      ]
    }
  }
}

Cursor~/.cursor/mcp.json

{
  "mcpServers": {
    "graphjin": {
      "command": "graphjin",
      "args": [
        "mcp",
        "--path",
        "<ABSOLUTE_PATH_TO_APP>"
      ]
    }
  }
}

VS Code.vscode/mcp.json

{
  "servers": {
    "graphjin": {
      "type": "stdio",
      "command": "graphjin",
      "args": [
        "mcp",
        "--path",
        "<ABSOLUTE_PATH_TO_APP>"
      ]
    }
  }
}

Codex~/.codex/config.toml

[mcp_servers.graphjin]
command = "graphjin"
args = ["mcp", "--path", "<ABSOLUTE_PATH_TO_APP>"]

Gemini CLITerminal

gemini mcp add --scope user graphjin graphjin -- mcp --path '<ABSOLUTE_PATH_TO_APP>'

Settings 3

`GRAPHJIN_USER_ID`	Optional: User ID the stdio session acts as; overrides mcp.stdio_user_id, overridden by --user-id.
`GRAPHJIN_USER_ROLE`	Optional: Role the stdio session acts as, which decides what it may query; overrides mcp.stdio_user_role.
`ANTHROPIC_API_KEY`	Optional: Model key that enables the built-in agent and ask_graphjin_agent; OPENAI_API_KEY or GOOGLE_APIKEY also work.

What it does

GraphJin is a Go service that reads the schema of the databases you point it at and turns GraphQL requests into single SQL statements. It supports PostgreSQL, MySQL, MongoDB, SQLite, Oracle, MSSQL, Snowflake, Redshift, BigQuery and Cassandra, plus object stores (local disk, S3, GCS) shown as tables and a CodeSQL index that makes a source tree queryable. The same engine serves an MCP surface, so an assistant can look up what tables, relationships and saved queries exist before it runs anything.

The MCP side is deliberately small. The base set is graphql_help and query_catalog for discovery, execute_saved_query for allow-listed queries and validate_where_clause for checking filters. execute_graphql (arbitrary queries) appears only when mcp.allow_raw_queries is on; get_current_config and validate_config appear only in dev mode, and update_current_config additionally needs mcp.allow_config_updates; ask_graphjin_agent appears only when the built-in agent is enabled with a model provider key. That makes nine tools at most, which the README never totals (serv/mcp.go, v3.21.13).

The README only shows the HTTP endpoint at /api/v1/mcp (Streamable HTTP, served by graphjin serve), but the binary also has a stdio mode: graphjin mcp --path <app folder>. When ~/.config/graphjin/client.json exists from graphjin mcp setup, the same command instead proxies stdio traffic to that remote GraphJin server (cmd/cmd_mcp.go). A built-in demo (graphjin mcp --demo) runs on SQLite with seeded data.

What it needs

Runtime	Node.js

The graphjin binary: npm install -g graphjin (its postinstall step downloads the platform binary), Homebrew, Scoop, .deb/.rpm releases or the dosco/graphjin Docker image. A GraphJin app folder made with graphjin serve new <name>, whose config holds the database connection strings. For the HTTP endpoint, start graphjin serve --path <app folder>. The optional built-in agent needs an OPENAI_API_KEY, ANTHROPIC_API_KEY or GOOGLE_APIKEY.

Limits

Without mcp.allow_raw_queries (default false in serv/config.go, auto-enabled in dev mode) an assistant can only run saved, allow-listed queries. Config tools exist only in dev mode; update_current_config also needs mcp.allow_config_updates (default false). In production mode CodeSQL stops watching source files live. Apollo Federation _entities resolution is not implemented yet. Some dialects do not support batched subscriptions. Legacy discovery tools and HTTP helper endpoints are off unless mcp.legacy_discovery is set.

Who it suits

Suits teams that want an assistant to query several company databases, warehouses and files through one permission-aware layer, with saved-query allow-lists and read-only flags rather than raw credentials, and who can run and configure a Go service. It is heavy for someone who only wants to ask questions of a single local database: it needs an app folder and config before it does anything beyond the demo. Pick it over a plain SQL server when you want role-based limits and audit logs around what the assistant can run.

Tools 9

graphql_help: Points the caller to the right catalog topic for a broad or unclear task
query_catalog: Searches or filters the catalog of tables, relationships, workflows, config recipes and policies
execute_saved_query: Runs a saved, allow-listed query by name with variables
validate_where_clause: Checks a filter against a table before it is used
execute_graphql: Runs an arbitrary GraphQL query or mutation; only when mcp.allow_raw_queries is on
get_current_config: Reads the running configuration or one section of it; dev mode only
validate_config: Dry-runs a configuration change without applying it; dev mode only
update_current_config: Changes configuration with preview then apply; dev mode with mcp.allow_config_updates
ask_graphjin_agent: Hands one instruction to the server-side agent and returns a typed answer; only when the agent is enabled

Popularity

75 popularity score, on our list (the bar is 36)

★ 3.2k ↓ 833/wk

GitHub stars	3,235	42.1 points
Stars in 30 days	+64	9.1 points
npm downloads, last week	833	23.4 points

Measured 2026-11-07. How the score works.

Where it is published

Code	dosco/graphjin ★ 3.2k
npm	graphjin 3.21.19, 2026-11-06

What it can reach

Runs	On your machine
Reaches	A database, Files on your machine, Your code, The internet
Changes things	Yes: it can write, send, create or delete
Sign-in	Other
Licence	Apache-2.0 (npm)
Last code change	2026-11-06

Runs on your machine (or your own host) and connects to the databases, warehouses, S3/GCS buckets and local folders named in its config, using credentials kept in that config; S3 and GCS use the standard AWS and Google credential chains. execute_graphql can run mutations when raw queries and mutations are allowed, which dev mode turns on automatically, and update_current_config can change database connections, tables and roles (its own config comment warns to enable it only in trusted environments). Tables and sources marked read_only are fixed at startup and cannot be unlocked by MCP config changes. The HTTP endpoint can require JWT or OAuth sign-in; stdio mode acts as the user and role set by flag, environment or config. The optional agent sends data to the chosen model provider.

Over time

GitHub stars 3.2k +64 (+2 %)

3.2k3.2k

8 Oct 20267 Nov 2026

npm downloads a week 833 −443 (−35 %)

4.8k1

20 Oct 20257 Nov 2026

Before the site measured it, read from npm's daily download counts.

Popularity score 75 +17 (+29 %)

7557

8 Oct 20267 Nov 2026

What is rising across the directory

Sources

Page checked 2026-10-14.

Badge for your README

Shows this server's rank in its category, and stars for a server that runs on your machine. It updates every hour.

MarkdownREADME.md

[![GraphJin on EveryMCPServer](https://everymcpserver.com/badge/graphjin.svg)](https://everymcpserver.com/servers/graphjin)

Connect your client

Add in one click

Or add it by command or config

Add in one click

Or add it by command or config

Settings 3

What it does

What it needs

Limits

Who it suits

Tools 9

Similar servers

Convex MCP Server

dbt MCP Server

SocratiCode

Instant MCP

trace-mcp

CodeQL Development MCP Server