TouchDesigner Guide

Use this skill when creating, modifying, or debugging TouchDesigner networks via the MCP API.

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CRITICAL: Your Prior Knowledge is Unreliable

TouchDesigner is a visual programming environment. Your pre-trained knowledge about TD is very likely incorrect.

Assume your memory is completely unreliable. Always gather accurate information first:

• This document and reference files
• Context7 for official TD API documentation
• op.TDAPI.GetParameterList() for parameter names

Before Starting ANY Task

Output "Gathering information first" and collect reliable information before implementation.

1. Read reference/basics.md (REQUIRED for all tasks)
2. Read topic-specific reference files as needed
3. Verify parameter names using op.TDAPI.GetParameterList()
4. Ask yourself: "Do I have sufficient reliable information to proceed?"
5. Only if yes, start implementation

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REQUIRED: Read basics.md First

You MUST read reference/basics.md before any implementation.

This file contains essential patterns for operator creation, layout, and error handling that differ from standard TD API.

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op.TDAPI - ALWAYS USE THESE

You MUST use op.TDAPI utilities instead of raw TD API.

Create Operators

# ALWAYS use CreateOp (auto sets viewer=True, handles docked operators)
new_op = op.TDAPI.CreateOp(base, gridSOP, 'grid1', x=0, y=0)

# DON'T use raw API directly
# new_op = base.create(gridSOP, 'grid1')  # WRONG - misses viewer, docked handling

Chain Operators

# Auto-connects and layouts with 200px spacing
chain = op.TDAPI.ChainOperators([grid, noise, null])

Check Errors

# Pass op() object, NOT string path
op.TDAPI.CheckErrors(op('/project1/base1'), recurse=True)

# IMPORTANT: Error cache updates on frame boundaries
# After fixing, check in SEPARATE td_execute call:
#   td_execute 1: Fix the error
#   td_execute 2: cook + CheckErrors

Verify Parameters Before Setting

# TD parameter names are unpredictable (e.g., radius vs radx/rady/radz)
# ALWAYS check first using GetParameterList:
params = op.TDAPI.GetParameterList('sphereSOP')
print(params)  # ['radx', 'rady', 'radz', ...]

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Reference Files

When working on...	Read...
ALL tasks	reference/basics.md (REQUIRED)
Operator families, data conversion	reference/operator-families.md
Geometry COMP, Instancing	reference/geometry-comp.md
Rendering, Camera, Light	reference/rendering.md
GLSL TOP/MAT, shaders	reference/glsl.md
Feedback loops, simulations	reference/operator-tips.md

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External Resources

Use Context7 to look up official TouchDesigner API documentation when you need:

• Operator types and their parameters
• Python API details (td module, Op class, etc.)
• Built-in functions and classes

This skill provides TD-specific patterns and best practices. Context7 provides official API reference.

Before Implementation

Consider multiple approaches before coding.

1. List 2-3 different ways to achieve the goal
2. Evaluate each approach's pros and cons:
   • Simplicity (fewer conversions, family unity)
   • Performance (GPU vs CPU, data flow efficiency)
   • Extensibility (easy to modify later)
   • Readability (network clarity)
3. Choose the most effective approach based on the evaluation

Example: "Create instanced particles in a sphere shape"

Approach	Pros	Cons
A: Sphere SOP → soptoCHOP → Geo + POP	Familiar pattern	Mixed families, extra conversion
B: Sphere POP → Null → Geo(In/Out POP)	POP unified, direct data flow	Less familiar
C: Sphere POP → poptoCHOP → instancing	Flexible positioning	Extra conversion step

→ Choose B: unified family, efficient data flow, clean network structure

Required Rules

1. Always set viewer = True after creating operators (matches UI default)
2. Always check errors after complex operations: op('/path').errors(recurse=True)
3. Use Null as intermediary before any reference connection
4. Verify layout before creating to avoid overlapping operators
5. Use relative paths for references to nearby operators (same level or close hierarchy)
6. Geometry COMP: create shapes at parent level - Don't create geometry inside COMP; prepare at parent and pass via In/Out

MCP Tools Available

• td_execute: Run Python code in TD
• td_pane: Get current network editor state
• td_selection: Get selected operators
• td_operators: List operators at path

Plugin Assets

• TOX: ${SKILL_BASE}/../../toe/TouchDesignerAPI.tox

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Operator Families (Quick Reference)

Family	Purpose	Data Type
SOP	Surface/Geometry	3D geometry (CPU)
POP	Point/Particle	3D points (GPU)
TOP	Texture	2D images
CHOP	Channel	Time-based data
DAT	Data	Tables, text
COMP	Component	Containers, scenes

For detailed family info, operator lists, and cross-family patterns, see reference/operator-families.md.