---
title: Reference | Keycard
description: API, CLI, SDK, security, and infrastructure reference for building with Keycard.
---

Reference is for readers who already know what they need and want the exact surface area: API operations, CLI commands, SDK packages, infrastructure-as-code, or platform assurance details.

## API

- [API Reference](/api/index.md) documents Keycard resources, methods, request bodies, and responses.

## CLI And SDKs

- [CLI](/cli/index.md) installs the `keycard` command locally and documents day-to-day terminal usage.
- [MCP SDK](/sdk/mcp/index.md) adds OAuth authentication to MCP servers.
- [OAuth SDK](/sdk/oauth/index.md) exposes lower-level OAuth primitives.
- [Cloudflare Workers SDK](/sdk/cloudflare/index.md) supports edge deployments.
- [Agent-to-Agent SDK](/sdk/agent-to-agent/index.md) supports agent-to-agent delegation.

## Infrastructure

- [Terraform Provider](https://registry.terraform.io/providers/keycardai/keycard/latest/docs) manages Keycard configuration as code.

## Security And Standards

- [Security Architecture](/reference/security-architecture/index.md) explains Keycard’s platform controls, encryption model, token security, CMEK, PrivateLink, and threat model.
- [Standards & Protocols](/reference/standards/index.md) documents the protocols Keycard builds on.