houdini-dev

name	houdini-dev
description	Pipeline skill — development workflow helpers for authoring Houdini Python tools in a live session: attach a local project to sys.path, hot-reload modules by prefix or name, run module entrypoints or scripts with captured stdout/stderr/traceback, start a debugpy listener, introspect HOM objects/signatures/node-type categories, and inspect or trigger safe UI actions (headless-safe). Not for scene editing — use domain skills first.
license	MIT
compatibility	dcc-mcp-houdini 0.1+, Houdini 20.5+, dcc-mcp-core 0.17+
allowed-tools	Bash Read
metadata	{"dcc-mcp":{"dcc":"houdini","layer":"domain","stage":"pipeline","version":"1.0.0","tags":["houdini","development","debug","hot-reload","debugpy","introspection","hom","ui","diagnostics"],"search-hint":"develop houdini tools attach python project hot reload modules run entrypoint script debugpy attach introspect hom node type categories signatures ui snapshot headless diagnostics","tools":"tools.yaml"}}

houdini-dev

Development workflow helpers for agents iterating on Houdini Python tools. Stays outside the minimal startup surface (load explicitly with load_skill("houdini-dev")). The intended loop:

1. attach_project("/path/to/tool") once for the project root.
2. Edit files in the normal workspace.
3. reload_modules(prefix="mytool") → run_entrypoint("mytool.cli:main").
4. Inspect the concise stdout/stderr/traceback summary.

Set DCC_MCP_HOUDINI_DEV_ROOTS to a path-list of trusted roots to restrict which local projects attach_project / run_script will accept.

Tool groups

• dev-project: attach_project, reload_modules.
• dev-run: run_entrypoint, run_script (captured output).
• dev-debug: start_debugpy (safe 127.0.0.1:5678 default, already-running detection).
• dev-introspect (read-only): introspect_hom — members/signatures, node-type categories, and available node types.
• dev-ui: ui_snapshot (read-only), ui_action.

Context limitations

• Headless hython: ui_snapshot / ui_action return a clean supported=false result instead of failing when no UI is available.
• Trusted roots: when DCC_MCP_HOUDINI_DEV_ROOTS is set, project and script paths outside those roots are refused with a structured error.
• debugpy: requires debugpy installed in the Houdini Python env; a second call reports already_running=true rather than re-binding the port.
• HOM only with hou: introspect_hom and the UI tools require hou; they degrade through skill_error when it cannot be imported.

Tracer-bullet flow

1. attach_project("/projects/mytool")
2. introspect_hom(category="Sop", name_filter="attrib") → discover node types
3. reload_modules(prefix="mytool", reimport=true)
4. run_entrypoint("mytool.build:run", kwargs={"dry_run": true})
5. ui_snapshot() → confirm the active desktop when running interactively