# Massgen Config Creator

> Guide for creating properly structured YAML configuration files for MassGen. This skill should be used when agents need to create new configs for examples, case studies, testing, or demonstrating features.

- Skill: `majiayu000/massgen-config-creator` (Agent Skill, multi-file: 2 files)
- Install (CLI): `npx skillmds add majiayu000/massgen-config-creator`
- Raw SKILL.md: https://api.skillmd.com/api/skills/majiayu000/massgen-config-creator/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- License: MIT
- Author: majiayu000 (https://skillmd.com/u/majiayu000)
- Updated: 2026-09-09
- Page: https://skillmd.com/skills/majiayu000/massgen-config-creator

---


# Config Creator

This skill provides guidance for creating new YAML configuration files that follow MassGen conventions and best practices.

## Purpose

The config-creator skill helps you create well-structured, validated configuration files for MassGen agents. It ensures consistency across the codebase and helps avoid common mistakes.

## When to Use This Skill

Use the config-creator skill when you need to:

- Create example configs demonstrating new features
- Write configs for case studies or releases
- Build reusable multi-agent workflow configs
- Test new backend or tool integrations
- Share configuration patterns with users

## Authoritative Documentation

**IMPORTANT:** The primary source of truth for config creation is:

**📖 `docs/source/development/writing_configs.rst`**

This file contains:
- Complete config creation workflow
- All current conventions and rules
- Property placement reference
- Validation checklist
- Common patterns and examples
- Up-to-date templates

**Always consult this document** for the latest configuration standards.

## Critical Rules (Quick Reference)

### 1. Never Invent Properties

**ALWAYS read 2-3 existing configs first** to understand current conventions:

```bash
# Find similar configs
ls massgen/configs/tools/{category}/

# Read examples
cat massgen/configs/basic/multi/two_agents_gemini.yaml
cat massgen/configs/tools/mcp/filesystem_claude.yaml
```

### 2. Property Placement Matters

- `cwd` → **BACKEND-level** (individual agent workspace)
- `context_paths` → **ORCHESTRATOR-level** (shared read-only files)
- `enable_web_search` → **BACKEND-level**
- `enable_planning_mode` → **ORCHESTRATOR.COORDINATION-level**

See `docs/source/development/writing_configs.rst` for complete property reference.

### 3. Key Conventions

✅ **DO:**
- Prefer cost-effective models (gpt-5-nano, gpt-5-mini, gemini-2.5-flash)
- Give all agents identical `system_message`
- Use separate workspaces per agent
- Include "What happens" comments explaining execution flow

❌ **DON'T:**
- Reference massgen v1 or legacy paths
- Invent new properties
- Suggest cleanup commands that delete logs

## Quick Start Workflow

### Step 1: Research Existing Configs

```bash
# Find configs in your category
ls massgen/configs/tools/{relevant_category}/

# Read 2-3 similar examples
cat massgen/configs/basic/multi/two_agents_gemini.yaml
```

### Step 2: Copy and Adapt

- Copy a similar config as your starting point
- Adapt values, never invent properties
- Follow the structure from existing configs

### Step 3: Test

```bash
massgen --config massgen/configs/tools/{category}/{your_config}.yaml "Test prompt"
```

### Step 4: Validate

Refer to the validation checklist in `docs/source/development/writing_configs.rst`

## File Naming and Location

**Naming Pattern:**
```
{agent_description}_{feature}.yaml
```

**Location Categories:**
- `massgen/configs/basic/` - Simple examples
- `massgen/configs/tools/filesystem/` - Filesystem operations
- `massgen/configs/tools/web-search/` - Web search
- `massgen/configs/tools/code-execution/` - Code execution
- `massgen/configs/tools/multimodal/` - Image, vision, audio
- `massgen/configs/tools/mcp/` - MCP integrations
- `massgen/configs/tools/planning/` - Planning mode

## Common Patterns (Quick Reference)

### Single Agent
```yaml
agent:  # Singular
  id: "my_agent"
  backend:
    type: "claude"
    model: "claude-sonnet-4"
```

### Multi-Agent
```yaml
agents:  # Plural
  - id: "agent_a"
    backend:
      type: "openai"
      model: "gpt-5-mini"
    system_message: "Shared task description"

  - id: "agent_b"
    backend:
      type: "gemini"
      model: "gemini-2.5-flash"
    system_message: "Shared task description"
```

### With Filesystem Access
```yaml
agents:
  - backend:
      cwd: "workspace1"  # Backend-level

orchestrator:
  context_paths:  # Orchestrator-level
    - path: "massgen/configs/resources/v0.0.29-example/source"
      permission: "read"
```

## Reference Files

**Primary Documentation:**
- **Config writing guide**: `docs/source/development/writing_configs.rst` ⭐ START HERE
- **YAML schema reference**: `docs/source/reference/yaml_schema.rst`
- **Example configs**: `massgen/configs/`

**Supporting Documentation:**
- **Supported models**: `docs/source/reference/supported_models.rst`
- **Backend configuration**: `docs/source/user_guide/backends.rst`
- **MCP integration**: `docs/source/user_guide/mcp_integration.rst`

## Tips for Agents

When creating configs programmatically:

1. **Always read the authoritative docs first**: `docs/source/development/writing_configs.rst`
2. **Read existing configs** to understand current patterns
3. **Copy structure** from similar configs, don't invent
4. **Test immediately** after creating
5. **When in doubt**, consult the full guide in `docs/source/development/writing_configs.rst`

This skill is a quick reference guide. For comprehensive, up-to-date information, always refer to the official documentation files listed above.