Terno MCP Connector

1. What It Connects To

Terno works with any database you've configured in your Terno organisation — PostgreSQL, MySQL, Snowflake, BigQuery, Databricks, Oracle, and others. If your warehouse already holds your sales, marketing, or operational data, this connector lets you ask questions about it directly from your AI assistant.

2. Compatible AI Clients

Terno works with Claude (claude.ai, Claude Desktop, Claude Code) and ChatGPT out of the box, and with any other AI application built on the open Model Context Protocol standard. Authentication uses standard OAuth 2.0 with Dynamic Client Registration, so any MCP-compatible client can connect without custom integration work.

3. What You Can Do

Every connection includes read access:

Browse your connected databases, tables, and columns.
Run read-only SQL queries and see results in the conversation.
Preview sample data from any table.
Search notes your team has saved about your data ("memories").

Organisation administrators can additionally grant write access, which allows:

Adding or removing a database connection in Terno (see below — this never touches the actual database).
Refreshing schema metadata after your database changes.
Maintaining display names and descriptions for tables and columns, and a shared organisation prompt.
Saving, editing, and deleting notes about your data for your team.

4. Write Access Never Touches Your Actual Data

This is the most important thing to understand about write access: every write operation modifies only Terno's own records about your data — never your database, its tables, or its rows.

"Delete a database connection" removes Terno's stored reference to that connection. It does not drop, truncate, or alter your actual database in any way — your database and everything in it are untouched and remain exactly as they were.
"Rename a table/column" and "Describe a table/column" only change the display name and description Terno shows for that table or column. Your database's real table and column names are never modified — Terno tracks them separately, precisely so its own display labels can never be confused with, or overwrite, your real schema.
Memories and the organisation prompt are notes stored entirely within Terno, about your data — not stored in, or written to, your database.

Reading your data works differently and is separately protected: every query is mediated by SQLShield, which permits only read-only SELECT statements. Statements that could modify data — INSERT, UPDATE, DELETE, DROP, and others — are rejected before they ever reach your database.

Put simply: no action available through this connector, read or write, can change, delete, or damage your actual data. Write access changes how Terno labels and organizes what it knows about your database — never the database itself.

5. How Credentials Are Handled

Your database password is never sent through the conversation. Adding a database is done by signing in to Terno directly and entering connection details there, over a normal authenticated web session. The AI assistant only ever receives a link to that page — never a credential, and the link itself grants no access on its own.

6. Authentication

Terno uses OAuth 2.0 with Dynamic Client Registration. Connecting requires an existing Terno account; new users are guided through creating one automatically as part of the connect flow. Access can be revoked at any time from your Terno account.

Server URL: https://mcp.terno.ai/mcp

7. Access Levels

Read — available to any connected member. Grants viewing data and running queries.
Write — available to organisation admins only. Grants adding/removing connections, editing metadata, and managing memories.

Write access is only usable while you remain an organisation admin — it does not persist if your role changes, even if a client's connection was originally granted it.

8. Use Case Examples

"Which of my databases have a customers table, and what columns does it have?"
"Show me total revenue by month for the last quarter."
"What has our team already noted about the orders table's date_created column?"
"Add a note explaining why the legacy_users table should be ignored."
(admins) "Connect our new Snowflake warehouse."
(admins) "Refresh the schema for our Postgres connection — we just added a table."

9. Troubleshooting

No databases connected yet

Ask your assistant to connect a database. It will return a secure link to Terno — open it and add your connection there. Credentials are never requested in the conversation.

A write action was refused

Adding or removing a connection, editing descriptions, and managing memories all require organisation admin access in Terno. Ask an existing admin to grant it, or connect using an admin account. Losing admin status also suspends write access immediately, even on an existing connection.

A table or column isn't showing up correctly

Terno tracks a display name for tables and columns separately from your database's real names. If you've recently changed your database's schema, ask an admin to refresh the schema metadata so Terno picks up the change.