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hiiu mcp

Run the MCP server on stdio, so a coding agent can act on a workspace instead of only reading it.

hiiu mcp

Runs hiiu's MCP server on stdio until stdin closes. This is what lets a designer's coding agent do things to a workspace rather than only read one.

Arguments and flags

No arguments, and no command-specific flags. Every global flag applies except one, and the exception is deliberate.

The tools it exposes

Tool What the agent can do
routes List the routes the base knows about
fork Materialise a base into a workspace
stub Answer an endpoint that went unmatched
scenario List and switch scenarios
share Bundle the workspace

Component search is deliberately not here. It ships as hiiu components search, a shell command an agent can run like any other, because a tool call that only reads is a tool call an agent did not need.

--json is refused, not ignored

Every other command promises that stdout carries exactly one JSON document keyed by ok. MCP's contract is the opposite: stdout is the transport, one newline delimited JSON-RPC frame per request, for the life of the process. Many documents, none of them carrying ok.

Silently exempting the flag would leave a runner that appends --json to every hiiu invocation believing it opted into the one document contract when it did not. Refusing to start is the honest answer.

Wiring it to an agent

Name it in the MCP config your agent reads. For Claude Code that is .mcp.json at the workspace root:

{
  "mcpServers": {
    "hiiu": { "command": "hiiu", "args": ["mcp"] }
  }
}

command: hiiu resolves on PATH, the same assumption every other document in a forked workspace makes.

Exit codes

Code When
0 stdin closed and the server stopped
2 --json was passed