---
title: Codex Integration
description: How to connect OpenAI Codex and Codex CLI with Siglata's hosted MCP tools and file catalog.
sidebar:
  label: Codex
  order: 3
---

Codex integrates with Siglata through the official `@siglata` Agent Plugin and Model Context Protocol (MCP) server.

## Installation

Start the supported Siglata installer:

```bash
siglata install
```

Or configure Codex's tool discovery file directly:

```json
{
  "plugins": ["@siglata/files"],
  "mcp": {
    "siglata": {
      "type": "streamable-http",
      "url": "https://www.siglata.com/v1/mcp",
      "headers": {
        "Authorization": "Bearer ${SIGLATA_API_KEY}"
      }
    }
  }
}
```

## How Codex Interacts with Siglata

1. **Context Initialization**: Codex calls `context` to verify organization permissions and limits.
2. **File Downloads & Ingestion**: When files or spreadsheets are passed to Codex, Codex passes the download URL; Siglata fetches, computes SHA-256 checksums, and safely binds bytes into the vault.
3. **Transactional Execution**: Codex plans edits using `execute({ mode: "plan" })`, reviews the mutation digest, and commits with `execute({ mode: "apply" })`.

## Example Prompt

```text
Use Siglata to inspect our Q3 Revenue spreadsheet, calculate the total across all regional sheets, and add a summary row.
```