API Reference

The NAICS MCP Server exposes 20+ tools through the Model Context Protocol. This reference documents each tool’s purpose, parameters, and usage.

Tool Categories

Tools for finding NAICS codes:

Tool	Purpose
`search_naics_codes`	Hybrid semantic + lexical search
`search_index_terms`	Search 20,398 official index terms

Tools for navigating the NAICS structure:

Tool	Purpose
`get_code_hierarchy`	Full ancestor chain for a code
`get_children`	Immediate children of a code
`get_siblings`	Same-level codes under parent
`get_parent`	Direct parent code
`get_ancestors`	All ancestors to sector level

Tools for classifying businesses:

Tool	Purpose
`classify_business`	Detailed single classification
`classify_batch`	Classify up to 100 descriptions
`validate_classification`	Verify a proposed code

Tools for analysis and comparison:

Tool	Purpose
`compare_codes`	Side-by-side code comparison
`find_similar_industries`	Find related industries
`get_cross_references`	Get exclusions and see-also refs
`get_sector_summary`	Sector statistics
`get_similar_codes`	Pre-computed similar codes (fast)
`get_cross_sector_alternatives`	Find codes in different sectors
`get_relationship_stats`	Relationship statistics for a code

Tools for audit trails and documentation:

Tool	Purpose
`write_to_workbook`	Save classification decision
`read_workbook`	Retrieve saved classifications

Tools for server health and guidance:

Tool	Purpose
`ping`	Quick health check
`get_server_health`	Detailed component status
`check_readiness`	Kubernetes readiness probe
`get_workflow_guide`	Classification workflow guidance


1. classify_business(description)
2. If low confidence → present alternatives
3. If cross-ref warnings → explain exclusions


1. search_naics_codes(query, limit=5)
2. get_code_hierarchy(top_result)
3. get_cross_references(top_result)


1. validate_classification(description, proposed_code)
2. If invalid → classify_business(description)

All tools return structured responses. Errors include:


{
  "error": "Error message",
  "code": "ERROR_CODE",
  "details": { ... }
}

Common error codes:

Code	Meaning
`INVALID_CODE`	NAICS code doesn’t exist
`INVALID_INPUT`	Missing or malformed parameter
`RATE_LIMITED`	Too many requests
`NOT_READY`	Server still initializing