eCFR Search: Find Code of Federal Regulations Sections by Keyword

ecfr/search

Searches the full text of the Code of Federal Regulations, the U.S. federal rules, for a word or phrase and returns the matching sections with their title, chapter, part and section numbers and names, a short excerpt around the match, the date each version took effect and, for a version no longer in force, the date it ended. Returns the first page of results, plus a meta block with the total match count. Matched terms in headings and excerpts are wrapped in HTML strong tags. The eCFR is not the official legal edition of the CFR. Data from the Office of the Federal Register's eCFR, as served by Eden Engine; not an official eCFR product.

activeper callv1

Price

$0.0026 per call

You pay the price shown. If a call turns out to cost more than its quote, you pay the actual price, capped at twice the quote. No monthly minimum. Top-ups start at $5.

Data source

Office of the Federal Register (eCFR)

Data from the Electronic Code of Federal Regulations (eCFR), published by the Office of the Federal Register. Served by Eden Engine; not an official Office of the Federal Register product.

Use it

Five steps: search, inspect, learn, run, settle. No per-tool setup; your agent reaches this tool through the meta-tools it already has.

Connect once and your AI can find and run this tool, and any other it needs.

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agent

// 1. search: find the tool
omnial_search({ query: "what you need" })

// 2. inspect: price and input schema
omnial_inspect({ tool: "ecfr/search" })

// 3. learn: read the usage guide at runtime
omnial_learn({ tool: "ecfr/search" })

// 4. run: price the exact call first, then run it
omnial_execute({ tool: "ecfr/search", input: { /* see input_schema */ }, dry_run: true })
omnial_execute({ tool: "ecfr/search", input: { /* ... */ } })

// 5. settle: the call is charged when it finishes, nothing to do

Not connected yet? Point your MCP client at https://mcp.eden-engine.com/mcp, then copy a config for your client.

Pricing

Every charge this tool can incur.

Charge	Price
Per call	$0.0026

Updated: Oct 20, 2026

Input and output schemas

Input schema

input_schema.json

{
  "type": "object",
  "required": [
    "query"
  ],
  "properties": {
    "query": {
      "type": "string",
      "maxLength": 300,
      "minLength": 1,
      "description": "The word or phrase to look for in the regulation text, for example privacy or lead paint disclosure."
    }
  },
  "additionalProperties": false
}

Output schema

output_schema.json

{
  "type": "object",
  "required": [
    "results"
  ],
  "properties": {
    "meta": {
      "type": "object",
      "description": "Paging and match count: current_page, total_pages, total_count, max_score and a description of the query.",
      "additionalProperties": true
    },
    "results": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "type": {
            "type": "string",
            "description": "Kind of match, for example Section."
          },
          "score": {
            "type": "number",
            "description": "Relevance score; higher is a better match."
          },
          "ends_on": {
            "type": [
              "string",
              "null"
            ],
            "description": "Date this version stopped being in effect; null for the version currently in effect."
          },
          "removed": {
            "type": "boolean"
          },
          "headings": {
            "type": "object",
            "description": "The names of each level. Matched terms are wrapped in strong tags.",
            "additionalProperties": true
          },
          "reserved": {
            "type": "boolean"
          },
          "hierarchy": {
            "type": "object",
            "description": "Where the section sits: title, subtitle, chapter, subchapter, part, subpart, subject_group, section, appendix. Unused levels are null.",
            "additionalProperties": true
          },
          "starts_on": {
            "type": "string",
            "description": "Date this version of the section took effect (YYYY-MM-DD)."
          },
          "change_types": {
            "type": "array",
            "items": {
              "type": "string"
            }
          },
          "structure_index": {
            "type": "integer"
          },
          "full_text_excerpt": {
            "type": [
              "string",
              "null"
            ],
            "description": "Text around the match, with matched terms in strong tags and span markers where text is skipped; null when there is none."
          },
          "hierarchy_headings": {
            "type": "object",
            "description": "The same levels with their labels, for example Title 48 and Part 24.",
            "additionalProperties": true
          }
        },
        "additionalProperties": true
      },
      "description": "Matching sections, each a version of a section with its dates. Empty when nothing matches."
    }
  },
  "description": "The eCFR search response: `results` holds the matching sections, best match first; `meta` describes the paging and the match count.",
  "additionalProperties": true
}