> ## Documentation Index
> Fetch the complete documentation index at: https://docs.querybear.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Codex

> Connect Codex CLI to your PostgreSQL, MySQL, or SQLite database using QueryBear's secure MCP server. Add to ~/.codex/config.toml.

**Codex** is OpenAI's terminal-based AI coding agent. It supports MCP via TOML configuration in `~/.codex/config.toml`. QueryBear plugs in as an `http` MCP server.

## Connect

Edit `~/.codex/config.toml` (create it if it doesn't exist) and add:

```toml theme={null}
[mcp_servers.querybear]
type = "http"
url = "https://mcp.querybear.com/mcp"
```

Restart the Codex CLI. The next tool call will trigger an OAuth handshake — Codex opens a browser, you approve, and it's linked to your QueryBear account.

### Verify

In a Codex session, ask:

> *"What QueryBear tools do you have?"*

You should see `list_connections`, `get_schema`, and `run_query`.

## Why QueryBear + Codex

Like other terminal agents, Codex is at its best when it can see the systems you're working on. Databases are the highest-leverage thing to expose — and the most dangerous to expose naively. QueryBear gives Codex safe read access:

* Generate SQL backed by real schemas, not hallucinated columns.
* Answer "is this row what I think it is?" without leaving the terminal.
* Cross-reference data between tables when debugging.
* Build one-off analytics queries during a refactor.

All with the security guarantees of QueryBear's gateway — read-only, allow-listed, audit-logged.

## Per-database setup guides

<CardGroup cols={2}>
  <Card title="PostgreSQL + Codex" href="/guides/postgres-codex">
    Step-by-step Postgres setup, including read-only role SQL.
  </Card>

  <Card title="MySQL + Codex" href="/guides/mysql-codex">
    Step-by-step MySQL setup, including read-only user SQL.
  </Card>

  <Card title="SQLite + Codex" href="/guides/sqlite-codex">
    Local SQLite file setup.
  </Card>
</CardGroup>

## Tips for using QueryBear in Codex

* **TOML formatting matters.** A misplaced `=` will silently disable the MCP server. If `querybear` doesn't appear in Codex's tool list, re-check the TOML block — common mistakes: missing `type = "http"`, mistyped URL, indentation in places TOML doesn't allow.
* **Be explicit about which connection.** Codex tends to ask for `list_connections` repeatedly if you don't name your target — *"using the prod connection, count..."* skips the round-trip.
* **The audit log lives in QueryBear.** If a Codex session ran a query you don't recognize, you can confirm in the QueryBear dashboard.

## Common workflows

* *"Pull the schema for the `events` table and write a query that counts unique sessions per day for the last 30 days."*
* *"What's the row count in `users`, `subscriptions`, and `payments`? I'm sizing a backfill."*
* *"Verify that no row in `orders` has `status = 'pending'` older than 24 hours."*

## Related

* [Quickstart](/quickstart) — full QueryBear setup
* [Security model](/features/security) — what the gateway enforces
* [Claude Code](/clients/claude-code) — Anthropic's terminal CLI alternative