feat(tools): rename start_here to tools_documentation with depth control (v2.7.4)

- Renamed start_here_workflow_guide to tools_documentation for clarity
- Added depth parameter to control documentation detail (essentials/full)
- Converted output from JSON to LLM-friendly plain text format
- Added per-tool documentation capability
- Created two-tier documentation system:
  - Essentials: brief info with key parameters and tips
  - Full: comprehensive docs with examples and best practices
- Documented 8 commonly used MCP tools
- Removed 380+ lines of unused getWorkflowGuide method
- Fixed duplicate tool definitions
- Updated all documentation references
- Added test script for tools documentation

BREAKING CHANGE: start_here_workflow_guide renamed to tools_documentation

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

docs/tools-documentation-usage.md

@@ -0,0 +1,135 @@
+# MCP Tools Documentation Usage Guide
+
+The `tools_documentation` tool provides comprehensive documentation for all MCP tools, making it easy for LLMs to understand how to use the tools effectively.
+
+## Basic Usage
+
+### 1. Get Documentation for Specific Tools
+
+```json
+{
+  "name": "tools_documentation",
+  "arguments": {
+    "tools": ["search_nodes", "get_node_essentials"]
+  }
+}
+```
+
+Returns detailed documentation including parameters, examples, and best practices for the specified tools.
+
+### 2. Search Tools by Keyword
+
+```json
+{
+  "name": "tools_documentation",
+  "arguments": {
+    "search": "validation"
+  }
+}
+```
+
+Finds all tools related to validation, including their descriptions and use cases.
+
+### 3. Browse Tools by Category
+
+```json
+{
+  "name": "tools_documentation",
+  "arguments": {
+    "category": "workflow_management"
+  }
+}
+```
+
+Available categories:
+- **discovery**: Tools for finding and exploring nodes
+- **configuration**: Tools for configuring nodes
+- **validation**: Tools for validating configurations
+- **workflow_management**: Tools for creating and updating workflows
+- **execution**: Tools for running workflows
+- **templates**: Tools for working with workflow templates
+
+### 4. Get All Categories
+
+```json
+{
+  "name": "tools_documentation",
+  "arguments": {}
+}
+```
+
+Returns a list of all categories and the tools in each category.
+
+### 5. Include Quick Reference Guide
+
+```json
+{
+  "name": "tools_documentation",
+  "arguments": {
+    "tools": ["n8n_create_workflow"],
+    "includeQuickReference": true
+  }
+}
+```
+
+Includes a quick reference guide with workflow building process, performance tips, and common patterns.
+
+## Response Format
+
+The tool returns structured documentation with:
+
+- **Parameters**: Complete parameter descriptions with types, requirements, and defaults
+- **Return Format**: Example of what the tool returns
+- **Common Use Cases**: Real-world scenarios where the tool is useful
+- **Examples**: Working examples with input and expected output
+- **Performance Notes**: Speed and efficiency considerations
+- **Best Practices**: Recommended usage patterns
+- **Common Pitfalls**: Mistakes to avoid
+- **Related Tools**: Other tools that work well together
+
+## Example: Learning About search_nodes
+
+Request:
+```json
+{
+  "name": "tools_documentation",
+  "arguments": {
+    "tools": ["search_nodes"]
+  }
+}
+```
+
+Response includes:
+- How to search effectively (single words work best)
+- Performance characteristics (fast, cached)
+- Common searches (http, webhook, email, database, slack)
+- Pitfalls to avoid (multi-word searches use OR logic)
+- Related tools for next steps
+
+## Tips for LLMs
+
+1. **Start with categories**: Browse available tools by category to understand what's possible
+2. **Search by task**: Use search to find tools for specific tasks like "validation" or "workflow"
+3. **Learn tool combinations**: Check "Related Tools" to understand workflow patterns
+4. **Check examples**: Every tool has working examples to copy and modify
+5. **Avoid pitfalls**: Pay attention to "Common Pitfalls" to prevent errors
+
+## Integration with Workflow Building
+
+The documentation helps build workflows efficiently:
+
+1. **Discovery Phase**: Use `search_nodes` and `list_nodes` documentation
+2. **Configuration Phase**: Learn from `get_node_essentials` examples
+3. **Validation Phase**: Understand validation tool options and profiles
+4. **Creation Phase**: Follow `n8n_create_workflow` best practices
+5. **Update Phase**: Master `n8n_update_partial_workflow` operations
+
+## Performance Optimization
+
+The documentation emphasizes performance:
+- Which tools are fast (essentials) vs slow (full info)
+- Optimal parameters (e.g., limit: 200+ for list_nodes)
+- Caching behavior
+- Token savings with partial updates
+
+This documentation system ensures LLMs can use the MCP tools effectively without trial and error.