eCFR Titles List: Code of Federal Regulations Titles and Amendment Dates

ecfr/list-titles

Lists every title of the Code of Federal Regulations, the subject areas the U.S. federal rules are organised into, with each title's number, name, the date it was last amended, the date of its latest issue and the date the electronic data is current through. Reserved titles are returned with null dates. Use it to see which titles exist and how recently each one changed; it does not return regulation text. 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.

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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/list-titles" })

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

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

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

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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",
  "properties": {},
  "additionalProperties": false
}

Output schema

output_schema.json

{
  "type": "object",
  "required": [
    "titles"
  ],
  "properties": {
    "titles": {
      "type": "array",
      "items": {
        "type": "object",
        "required": [
          "number",
          "name",
          "reserved"
        ],
        "properties": {
          "name": {
            "type": "string",
            "description": "The title's name, for example Food and Drugs."
          },
          "number": {
            "type": "integer",
            "description": "The CFR title number."
          },
          "reserved": {
            "type": "boolean",
            "description": "True for a title number held in reserve, which has no content."
          },
          "up_to_date_as_of": {
            "type": [
              "string",
              "null"
            ],
            "description": "Date the electronic data for the title is current through (YYYY-MM-DD); null for a reserved title."
          },
          "latest_amended_on": {
            "type": [
              "string",
              "null"
            ],
            "description": "Date the title was last amended (YYYY-MM-DD); null for a reserved title."
          },
          "latest_issue_date": {
            "type": [
              "string",
              "null"
            ],
            "description": "Date of the title's latest issue (YYYY-MM-DD); null for a reserved title."
          }
        },
        "additionalProperties": true
      },
      "description": "One entry per CFR title, in title-number order."
    }
  },
  "description": "The eCFR titles list.",
  "additionalProperties": true
}