A gateway between AI agents and your Postgres databases.
Every statement is checked against your policy and recorded before it runs.

Quickstart · Documentation · Midplane Cloud

Agents get useful once they can read your real tables, but a database role that reads every column and writes every row is not a control you can show a security reviewer. Midplane is that control. Agents connect to the gateway over MCP; it parses each statement with Postgres' own parser, decides it against your policy, records it, and only then runs it, with masks written into the query itself. ![Claude Code on the quickstart's sample database: emails come back hashed and phones cut to their last four digits; a support ticket carries a prompt injection asking for the API keys; once the agent has read it, Midplane denies the api_keys table.](docs/images/quickstart-demo.gif) ## What it enforces - **Table access**, denied by default, per table. - **Masking** at the source: hashes, partial values, generalized dates, NULLs, applied before any filter, join or aggregate sees the raw value. - **Guardrails**: one statement at a time, writes need a `WHERE`, no writes hidden in a `WITH`, reads in read-only transactions with timeouts. - **Approvals**: writes held for a person, bound to the exact statement and checked against the row count the approver saw. - **Containment**: once an agent reads a column labeled untrusted (support tickets, emails), its writes are held and secret tables are closed to it. - **An audit log** on the gateway's own disk, hash-chained, exported and verified with one command. The gateway runs in your network, next to your databases. It opens its connections to Midplane Cloud and to Midplane's relay, and neither connects to it. ![An AI agent connects over MCP to Midplane's relay; its queries and results are encrypted end to end, and the relay forwards them without being able to read them. In your network, the Midplane gateway checks, records and runs each statement, writes it to the audit log before it runs, and queries Postgres as its own role. Both of its other connections are outbound: to the relay, which agents' traffic comes in over, and to Midplane Cloud, which gets the query log with values removed and sends signed policies and approvals. Midplane Cloud gets no query results and no credentials.](docs/images/architecture.png) Behind the relay, agents reach the gateway at a public HTTPS URL while it only connects out, even in a private network: the relay passes their encrypted traffic without reading it ([how it works](https://midplane.ai/docs/how-it-works#through-the-relay)). On your computer or at [your own URL](https://midplane.ai/docs/gateway/deploy#your-own-url), agents connect to the gateway directly, with no relay. ## Get started - **A sample database, no account**: the [quickstart](#quickstart) below. - **Your own database, with Midplane Cloud**, for policy in a dashboard, approvals and a query log; the cloud never holds a database credential or sees a row. Follow [get started](https://midplane.ai/docs/get-started). Midplane Cloud is invite-only for now: [get access](https://midplane.ai/#get-access). - **Your own database, no account**: [local mode](https://midplane.ai/docs/gateway/local-mode). The gateway is the `midplane` npm package, run with `npx`, or the image `ghcr.io/midplaneai/midplane`. Both are built from this repository's tags with provenance, and the image is signed: [verifying a release](https://midplane.ai/docs/releases). ## Quickstart You need Node 24.16 or newer, Docker, and an MCP client such as Claude Code. ```sh git clone https://github.com/midplaneai/midplane.git cd midplane/examples/quickstart docker compose up -d --wait ``` Then follow [its steps](examples/quickstart): a sample shop database and the gateway in local mode, with nothing leaving your computer. Ask your agent: | Ask | What happens | | --- | --- | | "List our customers with their emails and phone numbers." | Emails hashed, phones cut to the last four digits, signup dates to the month | | "Delete all support tickets." | Denied: a write needs a `WHERE` | | "Mark ticket 2 as closed." | Held for approval; local mode has nobody to ask, so it's refused | | "Summarize ticket 1." | Its body carries a prompt injection; reading it taints the agent | | "Now show me the API keys." | Denied: a tainted agent can't read secret tables | In Midplane Cloud, **Try with sample data** runs the same sample linked, where the held write waits for your approval instead. ## Documentation [midplane.ai/docs](https://midplane.ai/docs): [how it works](https://midplane.ai/docs/how-it-works), [deploying the gateway](https://midplane.ai/docs/gateway/deploy), [configuration](https://midplane.ai/docs/gateway/configuration), [masking](https://midplane.ai/docs/policies/masking), [approvals and taint](https://midplane.ai/docs/policies/approvals-and-taint), [audit](https://midplane.ai/docs/audit) and [troubleshooting](https://midplane.ai/docs/troubleshooting). Its source is in [docs/](docs/). ## Contributing Bugs and questions go to [issues](https://github.com/midplaneai/midplane/issues); building and testing is in [CONTRIBUTING.md](CONTRIBUTING.md). Found a way around a mask, a policy or the audit log? Report it privately: [SECURITY.md](SECURITY.md). ## License MIT, see [LICENSE](LICENSE).