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OECD Transfer Pricing Guidelines API

Semantic search and retrieval API for the OECD Transfer Pricing Guidelines 2022. Build AI-powered transfer pricing tools with citation-grade accuracy.

  • 2,014 paragraphs indexed
  • Hybrid semantic + keyword search
  • LLM-ready context packs

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By creating an API key, you agree to our rate limits and fair use policy.

Rate Limits (Free Tier)

Search
60 requests/minute
Paragraphs
30 requests/minute
Context Pack
20 requests/minute

API Endpoints

GET/search

Semantic search across all paragraphs

/api/oecd/v1/search?q=DEMPE&top_k=10&chapters=VI

Parameters

q
Search query (required)
top_k
Results count (default: 10)
chapters
Filter by chapter (e.g., I,II,VI)

Features

  • Hybrid semantic + keyword search
  • Auto acronym expansion (DEMPE, APA, etc.)
  • Relevance scores included

GET/paragraphs

Fetch specific paragraphs by reference

/api/oecd/v1/paragraphs?refs=1.6,2.14,6.32

Parameters

refs
Comma-separated paragraph refs (max 20)

Returns full paragraph text with chapter, section, and navigation context.

GET/context-pack

LLM-ready context bundles

/api/oecd/v1/context-pack?topic=intangibles&max_paragraphs=15&format=markdown

Parameters

topic
Topic or question (required)
max_paragraphs
Max results (default: 15)
format
json or markdown

Returns

  • Pre-formatted context for LLM prompts
  • Ready-to-use citation string
  • Relevance-sorted paragraphs

Quick Start

# Search for paragraphs
curl "https://armslength.ai/api/oecd/v1/search?q=arm's%20length%20principle&top_k=3" \
  -H "x-api-key: YOUR_API_KEY"

# Fetch specific paragraphs
curl "https://armslength.ai/api/oecd/v1/paragraphs?refs=1.6,1.7" \
  -H "x-api-key: YOUR_API_KEY"

# Get context pack for LLMs
curl "https://armslength.ai/api/oecd/v1/context-pack?topic=DEMPE&max_paragraphs=5" \
  -H "x-api-key: YOUR_API_KEY"

Sample Responses

// GET /search?q=arm's length principle&top_k=2

{
  "query": "arm's length principle",
  "results": [
    {
      "paragraph_ref": "1.118",
      "chapter": "Chapter I: The arm's length principle",
      "section": "D.1.2.2.2. Determining a risk-adjusted rate of return",
      "snippet": "Therefore, in determining the risk-adjusted rate, it is important to identify and differentiate the financial risk...",
      "scores": { "semantic": 0.408, "lexical": 0, "combined": 0.016 }
    },
    {
      "paragraph_ref": "9.6",
      "chapter": "Chapter IX: Transfer pricing aspects of business restructurings",
      "section": "A.2. Issues that are within the scope of this chapter",
      "snippet": "Business restructurings are typically accompanied by a reallocation of profit potential among the members...",
      "scores": { "semantic": 0, "lexical": 0.303, "combined": 0.016 }
    }
  ],
  "total": 2
}

Use Cases

RAG Applications

Use the context-pack endpoint to ground LLM responses with authoritative OECD citations.

Compliance Tools

Build tools that reference specific OECD paragraphs for transfer pricing compliance.

Research Assistants

Create semantic search interfaces over the OECD guidelines for TP professionals.

Documentation AI

Auto-cite relevant OECD paragraphs when generating transfer pricing documentation.

Ready to Build?

Get your free API key and start building AI-powered transfer pricing tools today.