ADR-001: MCP SDK Selection

Status

Accepted

Context

We need an MCP SDK for Go to build the computer-use server. Two options exist:

1. modelcontextprotocol/go-sdk — Official SDK maintained with Google. Supports MCP spec up to 2026-07-28. v1.7.0+.
2. mark3labs/mcp-go — Community SDK with 8.5k stars, 190 contributors, 73 releases. Supports MCP 2025-11-25.

Key considerations:

• We need stable, widely-adopted MCP spec version that agents support
• API ergonomics for tool registration and transport setup
• Ongoing maintenance and spec compatibility

Decision

Use modelcontextprotocol/go-sdk for the following reasons:

• Maintained by the protocol authors — guaranteed spec alignment
• Clean API design with mcp.NewServer + mcp.AddTool pattern
• Stdio transport built in
• v1.7.0 supports MCP 2025-11-25 and 2026-07-28 — we target 2025-11-25 for broad agent compatibility
• Google collaboration provides long-term maintenance guarantee

Consequences

• Easier: spec upgrades come from the same team that writes the spec
• Easier: less risk of SDK falling behind protocol changes
• Harder: fewer community examples than mark3labs/mcp-go (newer)
• Harder: API may change during v1.x development (mitigated by pinning to v1.6.1 for now)