# MCP or open-source plugin? > Choose how Architecture Studio reaches your assistant. Hosted MCP is the starting point; the open-source plugin is available for local installation and source customization. ## Start with hosted MCP Connect the hosted MCP to use the hosted Arch Studio release in your assistant. Choose the open-source plugin when you want to install and manage the public package yourself. These are separately versioned distributions, not identical catalogs. - [Connect the hosted MCP](https://architecturestudio.ai/docs/install?method=mcp) - [Explore the open-source plugin](https://github.com/AlpacaLabsLLC/skills-for-architects/tree/v1.5.1.2) ## What you get Hosted MCP: Arch Studio workflow instructions, references and supported operations delivered through a hosted MCP connection. Start here to use the hosted release. Open-source plugin: The public Arch Studio package installed in your host. Inspect its source and run its workflows with that host’s capabilities. - [MCP tool discovery](https://architecturestudio.ai/docs/tools) - [Public plugin README](https://github.com/AlpacaLabsLLC/skills-for-architects/blob/v1.5.1.2/README.md) ## Release and catalog Hosted MCP: Arch Studio 1.5.1.2: 61 workflows, 8 agent roles and 9 practice areas. Identity: hosted-1-5-1-2-0692a162. Open-source plugin: Arch Studio 1.5.1.2: 61 skills, 10 local helper tools and 8 agent roles. Identity: public-1-5-1-2. - [Hosted release](https://architecturestudio.ai/releases/hosted-1-5-1-2-0692a162) - [Public release](https://architecturestudio.ai/releases/public-1-5-1-2) ## Where to use it Hosted MCP: Connect through a compatible Claude or ChatGPT app surface, Claude Code or Codex. Use the guide for your host; availability depends on its version, account plan and administrator permissions. Open-source plugin: Install with a supported plugin interface. The public package supports Claude Code and Codex; the guide also describes applicable app installation flows. Host-specific features are not identical across surfaces. - [Choose a host and installation method](https://architecturestudio.ai/docs/install) - [Host packaging and features](https://github.com/AlpacaLabsLLC/skills-for-architects/blob/v1.5.1.2/README.md) ## Arch Studio account Hosted MCP: Sign in to Arch Studio and authorize the MCP through your host’s OAuth flow. Website sign-in alone does not connect your assistant. Signup opens your account before installation. Open-source plugin: No Arch Studio account is required. Your host account and its own permissions still apply. - [Authentication and permissions](https://architecturestudio.ai/docs/auth) - [Installation](https://architecturestudio.ai/docs/install) ## Tools and execution Hosted MCP: Workflows are operation contracts performed by your assistant’s own tools; no local runner is required. The published executable-operation count is 1. Discover current schemas through MCP. Open-source plugin: Helpers execute through your host’s permitted local tools. Install the required runtimes and dependencies; plugin installation alone does not supply every external integration or execution capability. - [Tool execution boundaries](https://architecturestudio.ai/docs/tools) - [Public tooling catalog](https://github.com/AlpacaLabsLLC/skills-for-architects/blob/v1.5.1.2/skills/README.md) ## Files and privacy Hosted MCP: Your assistant controls workspace access and the model conversation. Inputs explicitly sent to hosted Arch Studio tools reach the service. Connecting MCP does not automatically upload or synchronize studio/project records. Open-source plugin: Studio records and firm-created skills stay in your selected workspace. Files and prompts sent to the model follow the host provider’s terms; research and external integrations have their own data handling. - [Arch Studio privacy and data handling](https://architecturestudio.ai/privacy) - [Plugin data governance](https://github.com/AlpacaLabsLLC/skills-for-architects/blob/v1.5.1.2/docs/data-governance.md) ## Your firm’s methods Hosted MCP: Give your assistant access to the firm context, standards and procedures it needs. The MCP does not provide a hosted editor, shared project database or automatic publication of private firm skills. Open-source plugin: Create private studio or project skills outside the installed plugin cache. Use a fork when you need to change the distributed source itself; ordinary firm extensions do not require one. - [Agent responsibilities](https://architecturestudio.ai/docs/agents) - [Extend your own studio](https://github.com/AlpacaLabsLLC/skills-for-architects/blob/v1.5.1.2/README.md) ## Updates and verification Hosted MCP: The service owner publishes hosted releases. Discover the release identity when using Arch Studio. Your account shows dated successful MCP discovery evidence, not continuous online status or proof that a workflow finished. Open-source plugin: Update through the host’s plugin process and review the selected release. Local plugins cannot be verified remotely; check installation in the host. Firm skills outside the plugin cache survive plugin updates. - [Release history](https://architecturestudio.ai/releases) - [MCP Connections](https://architecturestudio.ai/profile) - [Plugin update and extension guidance](https://github.com/AlpacaLabsLLC/skills-for-architects/blob/v1.5.1.2/README.md) ## Host access and costs Hosted MCP: In preview: free for firms, with no service commitments yet. Uses your assistant’s model access; an Arch Studio login does not include a Claude or ChatGPT subscription, and Arch Studio adds no charge on top of it. Shared memory, telemetry and permissions are in progress; account holders hear first. Open-source plugin: The public source is MIT-licensed and requires no Arch Studio account. Model access, local execution resources and any external services remain your responsibility. - [Plans](https://architecturestudio.ai/plans) - [Installation requirements](https://architecturestudio.ai/docs/install) - [Public license](https://github.com/AlpacaLabsLLC/skills-for-architects/blob/v1.5.1.2/LICENSE) ## A fork is a source choice A fork is your own copy of the open-source repository, not a third Arch Studio installation product or a copy of the hosted service. Use it to change the distributed code, packaging or shared defaults, and take responsibility for reviewing and maintaining those changes. For firm-specific procedures, begin with private studio/project skills outside the plugin cache. Keep client information and credentials out of public forks and contributions. - [Extension and contribution guidance](https://github.com/AlpacaLabsLLC/skills-for-architects/blob/v1.5.1.2/README.md) - [License](https://github.com/AlpacaLabsLLC/skills-for-architects/blob/v1.5.1.2/LICENSE) ## Account and email preferences An Arch Studio account supports identity and account operations and includes Product updates by default. Sign-up discloses that product and release updates are sent by email. Account holders can unsubscribe from any update or in Email preferences and can opt back in there. The public Product updates form remains a separate confirmed opt-in for people without an account. - [Email preferences](https://architecturestudio.ai/profile/email-preferences) - [Privacy and data handling](https://architecturestudio.ai/privacy)