The 2026 Connectivity Stack is a framework from the MCP team for how agents connect to external systems. The core claim: there is no single connectivity solution. The best agents in 2026 use three layers — Skills, MCP, and CLI/Computer Use — each suited to different constraints.
The Three Layers
Skills
Domain knowledge captured in simple files. Reusable instructions that tell the model what it knows and how to approach specific tasks. Mostly portable across platforms with minor differences. Skills are the cheapest and simplest connectivity primitive — no servers, no transport, no auth. They're just structured context.
Best for: domain expertise, workflow knowledge, coding patterns, operational playbooks.
MCP (Model Context Protocol)
Rich semantic connectivity with protocol-level primitives. MCP provides what simpler approaches cannot: UI rendering (MCP applications), structured authorization and governance, platform independence (same server works everywhere), long-running task management, resources as a data primitive, and elicitation for server-initiated user interaction.
Best for: SaaS integrations (Slack, Linear, Notion), systems requiring auth, remote/hosted tools, enterprise governance requirements, rich UI, and any scenario without a local sandbox.
CLI / Computer Use
Direct execution in a local environment. CLIs shine when the model can assume a sandbox, when the tool is already in pre-training data (git, GitHub CLI, npm), and when composability via bash piping is valuable. Computer use extends this to GUI-based interactions.
Best for: local coding agents, tools with strong CLI interfaces, anything where the model already knows the commands from pre-training.
Why This Matters
The framework resolves a common false dichotomy in agentic architecture: "should I use MCP or just call the CLI?" The answer is both, plus skills, depending on the task. A single agent session might load skills for domain knowledge, call MCP servers for SaaS connectivity and auth-gated systems, and shell out to git and npm for local operations.
The 2025 era of agents was dominated by coding agents — local, verifiable, sandbox-friendly. The 2026 shift is toward general knowledge-worker agents (financial analysts, marketing, operations) whose primary need is connectivity to multiple SaaS applications and shared drives. This shift makes MCP's strengths (auth, remote servers, platform independence) more critical than CLI's strengths (local execution, pre-training familiarity).
This framework is useful because it kills the "MCP for everything" and "just use the CLI" camps simultaneously. MCP is connective tissue, not a universal solution. The right question isn't "which one?" but "which layer handles this specific connection best?"
For MythOS and BrianBot: skills handle agent personality and workflow knowledge (augmentation memos, CLAUDE.md), MCP handles the knowledge library (MythOS MCP server), and CLI handles git, deployment, and local dev tooling. All three layers are already in use — this framework just names the pattern.