# MCP DB Connect [![npm version](https://img.shields.io/npm/v/mcp-db-connect.svg)](https://www.npmjs.com/package/mcp-db-connect) [![CI](https://github.com/phatngoit/MCP-DB/actions/workflows/ci.yml/badge.svg)](https://github.com/phatngoit/MCP-DB/actions/workflows/ci.yml) Universal MCP server for readonly-first access to Oracle Database, Microsoft SQL Server, PostgreSQL, MySQL/MariaDB, SQLite, MongoDB, and Qdrant vector search. This project is designed for AI tools that support the Model Context Protocol. Projects can install it, provide a YAML config, and expose safe database tools to their AI client. Oracle connections use the Node.js `oracledb` Thin mode by default, so Oracle Instant Client is not required for most databases. Some Oracle databases use NCHAR character sets that Thin mode cannot handle; those databases require Oracle Thick mode with Oracle Client libraries. By default, commands run from a project directory automatically use: - `mcp-db.local.yml`, then `mcp-db.yml`, then `mcp-db.yaml` - `.env` ## Features - Oracle, MSSQL, PostgreSQL, MySQL/MariaDB, SQLite, MongoDB, and Qdrant connectors - Multiple named connections in one config file - Readonly by default - SQL multi-statement blocking - MongoDB `$out` and `$merge` blocking in readonly mode - Row limits and query timeouts - Markdown table output for query results - Schema/table allowlist and denylist - Sensitive field masking - JSONL audit logs - Interactive setup wizard for AI clients and database connections - CLI for setup, init, validation, connection testing, and stdio/HTTP server startup - Docker image (multi-stage `Dockerfile`, published to GHCR on release) ## Install **1. Install the package** Node / TypeScript projects (local install): ```bash npm install --save-dev mcp-db-connect ``` .NET, Python, or other non-Node projects (global install): ```bash npm install -g mcp-db-connect ``` **2. Run the setup wizard** ```bash npx mcp-db-connect setup ``` The wizard asks which AI clients and databases to configure, then asks for one connection string per database (the same string your DB host, hosting provider, or existing app config already gives you) and writes all config files automatically. **3. Test your connections** ```bash npx mcp-db-connect test-connections ``` That's it — your AI client is now connected to your databases. ### What the wizard creates ```text mcp-db.local.yml # database connection config .env # local secrets .gitignore # keeps secrets and local config out of git .mcp.json # Claude Code MCP config (if selected) .codex/config.toml # Codex CLI config (if selected) .gemini/settings.json # Gemini CLI config (if selected) .kimi/mcp.json # Kimi CLI config (if selected) ``` ### Other setup options Skip the wizard with explicit flags: ```bash npx mcp-db-connect setup --ai claude,codex --db mssql,mongodb ``` Overwrite existing config entries: ```bash npx mcp-db-connect setup --force ``` Start an HTTP MCP endpoint instead of stdio: ```bash npx mcp-db-connect serve-http --host 127.0.0.1 --port 3000 npx mcp-db-connect serve-http --api-key-env MCP_DB_HTTP_API_KEY ``` ## AI Client Examples All examples assume the AI CLI is started from your application project root. ### Claude Code CLI Recommended automatic setup: ```bash mcp-db-connect setup --ai claude --db mssql ``` The generated `.mcp.json` uses `npx` so it works whether the package is installed globally or locally. #### Global install (`npm install -g mcp-db-connect`) `mcp-db-connect` is in PATH and can be used directly: ```bash claude mcp add --transport stdio db-connect --scope local -- mcp-db-connect start --project . --config ./mcp-db.local.yml --env ./.env ``` `.mcp.json`: ```json { "mcpServers": { "db-connect": { "command": "mcp-db-connect", "args": ["start", "--project", ".", "--config", "./mcp-db.local.yml", "--env", "./.env"], "env": { "LOG_LEVEL": "silent" } } } } ``` #### Local install (`npm install --save-dev mcp-db-connect`) Use `npx` so Claude Code can find the binary inside `node_modules/.bin`: ```bash claude mcp add --transport stdio db-connect --scope local -- npx mcp-db-connect start --project . --config ./mcp-db.local.yml --env ./.env ``` `.mcp.json`: ```json { "mcpServers": { "db-connect": { "command": "npx", "args": ["mcp-db-connect", "start", "--project", ".", "--config", "./mcp-db.local.yml", "--env", "./.env"], "env": { "LOG_LEVEL": "silent" } } } } ``` ### Codex CLI Recommended automatic setup: ```bash mcp-db-connect setup --ai codex --db mssql,oracle,mongodb npm --prefix .\.mcp-tools\db-connect install codex ``` Project `.codex/config.toml`: ```toml [mcp_servers.db-connect] command = '.\.mcp-tools\db-connect\node_modules\.bin\mcp-db-connect.cmd' args = ["start", "--project", ".", "--config", '.\mcp-db.local.yml', "--env", '.\.env'] enabled = true [mcp_servers.db-connect.env] LOG_LEVEL = "silent" ``` The `.mcp-tools/db-connect/package.json` file created by the wizard uses `mcp-db-connect` from npm. Run the install command above once per project. ### Gemini CLI Recommended automatic setup: ```bash mcp-db-connect setup --ai gemini --db mongodb gemini ``` Project `.gemini/settings.json`: ```json { "mcpServers": { "db-connect": { "command": "npx", "args": ["mcp-db-connect", "start", "--project", ".", "--config", "./mcp-db.local.yml", "--env", "./.env"], "env": { "LOG_LEVEL": "silent" } } } } ``` ### Kimi CLI Recommended automatic setup: ```bash mcp-db-connect setup --ai kimi --db oracle kimi --mcp-config-file .\.kimi\mcp.json ``` Project `.kimi/mcp.json`: ```json { "mcpServers": { "db-connect": { "command": "npx", "args": ["mcp-db-connect", "start", "--project", ".", "--config", "./mcp-db.local.yml", "--env", "./.env"], "env": { "LOG_LEVEL": "silent" } } } } ``` Kimi CLI can also manage global MCP servers with `kimi mcp add`, but the project-local file above keeps this database MCP scoped to one project. ### Generic MCP JSON For clients that accept the common MCP JSON format: ```bash mcp-db-connect setup --ai generic --db mssql ``` Use `.mcp-db-connect/mcp.json`: ```json { "mcpServers": { "db-connect": { "command": "npx", "args": ["mcp-db-connect", "start", "--project", ".", "--config", "./mcp-db.local.yml", "--env", "./.env"], "env": { "LOG_LEVEL": "silent" } } } } ``` ## Streamable HTTP Client Use this endpoint for MCP clients or agents that support Streamable HTTP: ```text http://127.0.0.1:3000/mcp ``` Health check: ```text http://127.0.0.1:3000/healthz ``` ## Config ```yaml security: defaultMaxRows: 100 queryTimeoutMs: 10000 blockMultiStatement: true allowWriteOperations: false maskColumns: - password - token - secret - api_key auditLogPath: ./logs/mcp-db-connect.audit.jsonl connections: mssql_report: type: mssql host: 172.27.62.7 port: 1433 database: Internet username: report_reader passwordEnv: MSSQL_REPORT_PASSWORD encrypt: true trustServerCertificate: true mode: readonly mssql_write_model: type: mssql host: 172.27.62.8 port: 1444 database: InternetWrite username: writer_user passwordEnv: MSSQL_WRITE_PASSWORD encrypt: true trustServerCertificate: true mode: readonly oracle_local: type: oracle host: localhost port: 1521 serviceName: ORCLPDB1 username: app_readonly passwordEnv: ORACLE_PASSWORD clientMode: thin mode: readonly mssql_local: type: mssql host: localhost port: 1433 database: appdb username: sa passwordEnv: MSSQL_PASSWORD encrypt: true trustServerCertificate: true mode: readonly mongo_local: type: mongodb uriEnv: MONGODB_URI database: appdb mode: readonly postgres_local: type: postgres host: localhost port: 5432 database: appdb username: app_readonly passwordEnv: POSTGRES_PASSWORD mode: readonly mysql_local: type: mysql host: localhost port: 3306 database: appdb username: app_readonly passwordEnv: MYSQL_PASSWORD mode: readonly qdrant_local: type: qdrant url: http://localhost:6333 apiKeyEnv: QDRANT_API_KEY mode: readonly sqlite_local: type: sqlite file: ./data/appdb.sqlite mode: readonly ``` SQLite has no host/port/username — `file` is a path to the database file (relative paths resolve against the process's working directory), and `:memory:` is also accepted for an ephemeral in-process database. MongoDB stores the selected port inside the URI saved in `.env`, for example: ```dotenv MONGODB_URI=mongodb://user:password@localhost:27018/appdb ``` ### Oracle Thin vs Thick Mode Default Oracle setup uses `clientMode: thin` and does not need Oracle Instant Client: ```yaml connections: oracle_local: type: oracle host: localhost port: 1521 serviceName: ORCLPDB1 username: app_readonly passwordEnv: ORACLE_PASSWORD clientMode: thin ``` Oracle Instant Client is not required. If the database has `NCHAR`/`NVARCHAR2` columns with `NLS_NCHAR_CHARACTERSET = AL16UTF16`, the connector automatically rewrites the query to cast those columns to `VARCHAR2` server-side so Thin mode can handle them. ### Connection strings instead of individual fields Oracle, MSSQL, PostgreSQL, and MySQL/MariaDB also accept a raw connection string instead of `host`/`port`/`database`/`username`: ```yaml connections: mssql_from_string: type: mssql connectionStringEnv: MSSQL_FROM_STRING_CONNECTION_STRING mode: readonly oracle_from_string: type: oracle connectDescriptor: (DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(HOST=10.20.30.15)(PORT=1521)))(CONNECT_DATA=(SERVER=POOLED)(SERVICE_NAME=DEMOPDB1))) username: demo_ora_user passwordEnv: ORACLE_FROM_STRING_PASSWORD mode: readonly postgres_from_string: type: postgres connectionStringEnv: POSTGRES_FROM_STRING_CONNECTION_STRING mode: readonly mysql_from_string: type: mysql connectionStringEnv: MYSQL_FROM_STRING_CONNECTION_STRING mode: readonly ``` `connectionStringEnv` points to a full ADO/tedious connection string (MSSQL), a `postgres://user:password@host:5432/database` URI (PostgreSQL), or a `mysql://user:password@host:3306/database` URI (MySQL/MariaDB) in `.env` (same convention as MongoDB's `uriEnv`). `connectDescriptor` holds an Oracle TNS connect descriptor or Easy Connect string and is not secret — only the password goes in `.env`. The setup wizard generates these automatically from a pasted connection string; both forms can also still be hand-written using the structured `host`/`port`/... fields shown above. PostgreSQL and MySQL/MariaDB connections also accept `ssl: true` (with `rejectUnauthorized: false` for self-signed certificates common on managed database providers). ### Config via environment variable Every command that loads config (`start`, `serve-http`, `validate-config`, `test-connections`) also accepts the entire config document — the same `security` + `connections` structure normally stored in `mcp-db.local.yml` — as YAML or JSON in the `MCP_DB_CONFIG` environment variable, instead of a file: ```bash export MCP_DB_CONFIG=' connections: postgres_demo: type: postgres host: db.example.com port: 5432 database: appdb username: app_readonly password: change-me mode: readonly ' mcp-db-connect serve-http --host 0.0.0.0 --port 3000 ``` When `MCP_DB_CONFIG` is set, `--config`/`mcp-db.local.yml`/`mcp-db.yml`/`mcp-db.yaml` file discovery is skipped entirely — no file needs to exist. This is what lets container platforms that can't mount a project file into the container (Smithery.ai and similar hosted MCP platforms) run this server: they inject the whole config as one environment variable instead. Secrets can be embedded directly (as `password:`/`connectionString:` above) or still indirected through their own env var via `passwordEnv`/`connectionStringEnv`/etc. — both forms keep working exactly as they do with a file. ## Tools ### SQL (Oracle + MSSQL + PostgreSQL + MySQL/MariaDB + SQLite) - `db_list_connections` — List configured connections - `db_test_connection` — Test a connection - `db_list_schemas` — List schemas - `db_list_tables` — List tables - `db_describe_table` — Describe columns (including catalog comments where available), primary keys, foreign keys, and indexes - `db_query` — Run a readonly SQL query - `db_explain_query` — Return an execution plan for a SQL query - `db_count` — Count rows in a table with an optional WHERE clause `db_query` and `db_explain_query` accept an optional `params` array for bind parameters. Oracle and PostgreSQL use positional binds (`:1`, `:2`, ... for Oracle; `$1`, `$2`, ... for PostgreSQL); MySQL/MariaDB and SQLite use `?` placeholders in array order; MSSQL has no positional syntax, so params are bound as named parameters `@p1`, `@p2`, ... in the same order as the array. SQLite has no schema/database concept beyond `main` (plus any attached databases); `db_list_schemas` reflects that via `PRAGMA database_list`, and `db_explain_query` runs `EXPLAIN QUERY PLAN` rather than a cost-based plan. `db_describe_table` includes each column's catalog comment/description when the database has one set (Oracle `all_col_comments`, PostgreSQL `COMMENT ON COLUMN`, MySQL/MariaDB `COLUMN_COMMENT`, MSSQL `MS_Description` extended property) — the `comment` column in the output is only shown when at least one column actually has one. SQLite has no comment mechanism, so it's never populated there. ### MongoDB - `db_list_connections` — List configured connections - `db_test_connection` — Test a connection - `db_list_schemas` — List databases - `db_list_tables` — List collections - `db_describe_table` — Sample collection fields - `db_mongo_find` — Run a readonly find operation - `db_mongo_aggregate` — Run a readonly aggregate pipeline - `db_mongo_count` — Count documents with an optional filter - `db_mongo_get_indexes` — List indexes for a collection - `db_mongo_explain_find` — Return an execution plan for a find operation - `db_mongo_explain_aggregate` — Return an execution plan for an aggregate pipeline - `db_mongo_insert` — Insert one or more documents - `db_mongo_update` — Update documents matching a filter (`many: true` for all matches, otherwise just the first) - `db_mongo_delete` — Delete documents matching a filter (`many: true` for all matches, otherwise just the first) `db_mongo_insert`/`db_mongo_update`/`db_mongo_delete` are blocked unless the connection has `mode: readwrite` **and** `security.allowWriteOperations: true` — mirroring how write SQL statements are gated for the SQL connectors. `db_mongo_update` and `db_mongo_delete` also require a non-empty `filter`, so a mistaken `{}` can't silently update or delete an entire collection. `db_describe_table` infers MongoDB column types by sampling documents. The sample size defaults to 20 and can be set per-connection with `describeSampleSize`, or overridden per call with the tool's `sampleSize` argument: ```yaml connections: mongo_local: type: mongodb uriEnv: MONGODB_URI database: appdb describeSampleSize: 100 mode: readonly ``` `db_mongo_find` accepts an optional `skip` for pagination (skip the first N matching documents, then apply `maxRows` as the page size). ### Qdrant (vector search) - `db_list_connections` — List configured connections - `db_test_connection` — Test a connection - `db_list_tables` — List collections - `db_describe_table` — Describe a collection's vector config and payload field types - `db_qdrant_search` — Run a vector similarity search with an optional filter and score threshold - `db_qdrant_scroll` — Browse or filter points without a vector search - `db_qdrant_count` — Count points with an optional filter `db_list_schemas` returns an empty list for Qdrant connections since Qdrant collections aren't grouped into schemas/databases. `db_qdrant_scroll` supports paging through an entire collection: each response includes a `Next offset` line when more points remain — pass that value back as the `offset` argument on the next call to continue. Omit `offset` to start from the beginning. Query result tools return tables like: ```text Rows: 2 | id | name | | --- | --- | | 1 | Alice | | 2 | Bob | ``` ## CLI Commands - `mcp-db-connect setup` - `mcp-db-connect init` - `mcp-db-connect ai-config` - `mcp-db-connect validate-config` - `mcp-db-connect test-connections` - `mcp-db-connect start` - `mcp-db-connect serve-http --host 127.0.0.1 --port 3000` - `mcp-db-connect serve-http --api-key-env MCP_DB_HTTP_API_KEY` - `mcp-db-connect update` ## Updating `start` and `serve-http` check npm once a day (cached, non-blocking, silently skipped if offline) for a newer version and print a notice to stderr if one is available — this never touches stdout, so it's safe on the stdio transport. The check only looks within `^`, i.e. the current `0.x` minor line (for example, `0.1.21` only considers `0.1.22`, `0.1.23`, ... — never `0.2.0`). This project hasn't reached `1.0.0` yet, so a minor version bump could still contain breaking changes; the narrower range avoids silently jumping into one. Run the update yourself with: ```bash mcp-db-connect update # checks and installs, if available mcp-db-connect update --check-only # only checks, doesn't install mcp-db-connect update --range "^0.2.0" # override the range, e.g. to opt into a new minor line deliberately ``` It detects whether the package is installed globally or as a local project dependency and runs the matching `npm install` command. There is no fully silent background auto-install — updating always requires this one explicit command (or your own `npm install -g mcp-db-connect@latest` / `npm install --save-dev mcp-db-connect@latest`). ## Docker A multi-stage `Dockerfile` at the repo root builds the CLI into a standalone image. The container needs your project's `mcp-db.local.yml` and `.env` mounted in, since connection config is file-based rather than baked into the image. Pull the published image (built and pushed to GHCR on every release by `.github/workflows/release.yml`): ```bash docker pull ghcr.io/phatngoit/mcp-db-connect:latest ``` Or build it locally: ```bash docker build -t mcp-db-connect . ``` Run over stdio (for MCP clients that exec the container directly), mounting your project config. Replace `mcp-db-connect` with `ghcr.io/phatngoit/mcp-db-connect:latest` to use the published image instead of a local build: ```bash docker run -i --rm \ -v "$(pwd)/mcp-db.local.yml:/app/project/mcp-db.local.yml:ro" \ -v "$(pwd)/.env:/app/project/.env:ro" \ mcp-db-connect start --project /app/project ``` Run the Streamable HTTP transport, publishing a port: ```bash docker run --rm -p 3000:3000 \ -v "$(pwd)/mcp-db.local.yml:/app/project/mcp-db.local.yml:ro" \ -v "$(pwd)/.env:/app/project/.env:ro" \ mcp-db-connect serve-http --project /app/project --host 0.0.0.0 --port 3000 ``` Or use the `examples/docker-compose.server.yml` example, which builds the image and mounts `mcp-db.local.yml`/`.env` from the current directory: ```bash docker compose -f examples/docker-compose.server.yml up --build ``` ### Hosting on a cloud/container platform No file mount is required if you set `MCP_DB_CONFIG` instead (see [Config via environment variable](#config-via-environment-variable)). The image's entrypoint (`docker-entrypoint.sh`) also auto-switches from stdio to the Streamable HTTP transport when a `PORT` environment variable is present — the convention used by Smithery.ai, Railway, Render, Fly.io, and similar platforms — binding to `0.0.0.0:$PORT` without any command override: ```bash docker run -e PORT=8080 -e MCP_DB_CONFIG="$(cat mcp-db.local.yml)" -p 8080:8080 \ ghcr.io/phatngoit/mcp-db-connect:latest ``` ## Security Defaults The server is intentionally conservative: - Connections default to `readonly` - SQL write and DDL keywords are blocked unless global and connection config allow writes - SQL multi-statement execution is blocked - MongoDB aggregate write stages and `db_mongo_insert`/`db_mongo_update`/`db_mongo_delete` are blocked unless global and connection config allow writes - `db_mongo_update`/`db_mongo_delete` require a non-empty filter, so they can't accidentally affect an entire collection - Result rows are capped by config - Sensitive fields are masked recursively Use database accounts with the smallest permissions possible. The MCP layer is a guardrail, not a replacement for DB-level permissions. ## Registries - **[Official MCP Registry](https://registry.modelcontextprotocol.io)** — listed as `io.github.phatngoit/mcp-db-connect` via `server.json` at the repo root. The release workflow (`.github/workflows/release.yml`) publishes to this registry automatically after every npm release using GitHub Actions OIDC (no stored token needed). - **[Glama.ai](https://glama.ai/mcp/servers)** — indexed by crawling this repository; submitted manually, no manifest file required. - **Smithery.ai** — not yet submitted. The blockers are resolved: a `Dockerfile` (published to `ghcr.io/phatngoit/mcp-db-connect`), a `smithery.yaml` container-runtime manifest at the repo root, `MCP_DB_CONFIG` env-var config (no file mount needed), and a `PORT`-aware entrypoint that switches to the HTTP transport automatically. Submitting still requires a one-time manual step — connecting this repo through Smithery's GitHub App at `smithery.ai/new` — and `smithery.yaml`'s exact fields should be double-checked against Smithery's current docs first, since they weren't independently verifiable while writing it. ## Roadmap - OpenTelemetry tracing - Secrets manager integrations (AWS Secrets Manager, Azure Key Vault, HashiCorp Vault)