# CFR Section Lookup — Code of Federal Regulations Full-Text Retrieval

> CFR Section Lookup — Code of Federal Regulations Full-Text Retrieval is a paid API for AI agents from 2s.io, paid per call via x402, $0.0018/call, status unknown (last checked 2026-09-14).

Fetches the full plain-text of a specific Code of Federal Regulations (CFR) section by title and section identifier, with optional point-in-time historical date lookup.

## Facts

- Endpoint: GET https://2s.io/api/law/cfr-section
- Price: $0.0018/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/cfr-section-lookup-code-of-federal-regulations-full-text-retrieval-8ee62b2b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_VKTGfBqPSl2vjhcIdzbOu

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability cfr-section-lookup-code-of-federal-regulations-full-text-retrieval-8ee62b2b
```

Example prompt: What does 12 CFR 1026.43 say? Pull the full text of that section for me — that's Title 12 on Banks and Banking, section 1026.43.

## When to prefer this

Use this endpoint when you need the authoritative, full plain-text of a specific CFR section by exact citation, especially when you already know the title and section number. Ideal for compliance checking, legal research, regulatory verification, or retrieving historical regulatory text as of a specific date. Prefer this over general web search when you need precise, structured regulatory text with citation metadata.

## Known failure modes

- Invalid title number (must be 1-50) returns a validation error
- Malformed section identifier (must match pattern like '1026.43' or '240.10b-5') returns a validation error
- Section does not exist in eCFR returns empty items array
- Historical date before 2017-01-03 is out of coverage range
- Very large sections may have truncated text (truncated: true flag set)
- Payment failure (402) if USDC payment on Base or Solana is not attached

## How this service works

Fetch the authoritative text of any section of the US Code of Federal Regulations by title and section number — for example title 12, section 1026.43 returns Regulation Z’s ability-to-repay standards. Returns the canonical citation, section heading, full plain text, Federal Register source credit, the as-of date, and a link to the official eCFR page. An optional date parameter (YYYY-MM-DD) retrieves the historical text in force on that date, back to 2017. Data from the Electronic Code of Federal Regulations (US GPO / Office of the Federal Register), public domain, updated daily — verify regulatory citations against the authoritative source instead of relying on model memory.

## Output

Returns a JSON object with an array of items containing the section's canonical citation (e.g. '12 CFR 1026.43'), title number, part and section identifiers, official heading, full plain-text body, source credit/citation history, the as-of date the text reflects, whether the text was truncated, and the official eCFR URL. Also includes provenance metadata (provider, source URL, license).

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method",
    "queryParams"
   ],
   "properties": {
    "type": {
     "const": "http"
    },
    "method": {
     "const": "GET"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "title",
      "section"
     ],
     "properties": {
      "date": {
       "type": "string",
       "description": "Optional point-in-time date (YYYY-MM-DD). Returns the text in force on that date; coverage starts 2017-01-03. Defaults to the latest available text."
      },
      "title": {
       "type": "integer",
       "maximum": 50,
       "minimum": 1,
       "description": "CFR title number, 1-50 (e.g. 12 for Banks and Banking, 40 for Protection of Environment)."
      },
      "section": {
       "type": "string",
       "description": "Section identifier as \"part.section\", e.g. \"1026.43\" or \"240.10b-5\". The part is the digits before the dot."
      }
     },
     "additionalProperties": false
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/cfr-section-lookup-code-of-federal-regulations-full-text-retrieval-8ee62b2b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from 2s.io](https://www.zero.xyz/host/2s.io/llms.txt)