Model Context Protocol (MCP) is the fastest way to let an agent drive a tool without screen-scraping. But hand-writing an MCP server for every CLI is a maintenance tax. sapctl takes a different route: it emits an MCP server from its own command tree.
The insight
A Cobra command tree already encodes everything an MCP tool needs: a name, a description, flags, and a run function. The gap is a transport. sapctl walks the AST at runtime and exposes each sub-command as an MCP tool over JSON-RPC 2.0 stdio.
sapctl mcp serveThat single command turns the whole CLI into an MCP server. Claude Desktop, Cursor, and Continue can all connect to it.
How it works
The emitter walks the Cobra tree, and for each leaf command it:
- reads the
Usestring as the tool name, - reads the
Shortdescription as the tool description, - maps flags to JSON-schema parameters,
- registers a handler that invokes the command's
RunE.
Because the tree is the source of truth, the MCP surface can never drift from the CLI surface. Add a command, and it appears in the MCP server on the next run.
Why this matters for SAP
SAP API Policy v4/2026 requires agents to route through approved pathways rather than orchestrating raw APIs. An MCP server emitted from a CLI that only calls Published APIs is exactly that: the agent gets a constrained, auditable tool surface, and every call still writes to the signed audit chain.
What this buys you
An MCP server is not a separate product. It is a view over the same command tree. When the CLI and the agent surface share one source of truth, there is nothing to keep in sync, and nothing for an agent to bypass.