particlesystem

Unity Open MCP — Particle System Extension

Skill for AI agents driving Unity Particle System components in a project through the unity-open-mcp MCP server.

This domain is embedded in the bridge and opt-in. Its tools use the built-in ParticleSystem module — no Unity package install is required, and they compile into every bridge build. Its tool group is hidden from ListTools until the connected session activates it.

Preconditions

• Unity Editor is open with the target project.
• unity_open_mcp_ping returns connected: true.
• The particle-system tool group is activated — call unity_open_mcp_manage_tools(action="activate", group="particle-system") before invoking any particle_system_* tool. Fresh sessions start with two default-on groups (core and gate-and-verify); activate the other groups you need on demand. Because ParticleSystem is built-in, capabilities always reports the particle-system group as available: true.

Tool prefix

All tools in this pack use unity_open_mcp_particle_system_*. ParticleSystem is a scene component — the lone mutator (particle_system_modify) runs the full gate path with paths_hint scoped to the host's scene path; the read-only tool (particle_system_get) is gate-free.

Always get before you modify

particle_system_get is cheap (gate-free, read-only). Call it first to:

• confirm the target actually has a ParticleSystem component (returns component_not_found otherwise),
• see the runtime state (isPlaying, particleCount, time),
• read the current value of any module so you can decide what to patch.

Module surface (modify)

particle_system_modify takes a module discriminator + a fields_json JSON object of {field: value} entries to apply to that module. One module per call — chain multiple calls for multi-module edits.

Only the documented fields per module are accepted. Unknown fields land in unknownFields (and are skipped); the call still succeeds so the agent can iterate on the valid subset. Bad-typed values land in errors.