# eCFR amendment history

Dated list of amendments to a CFR part or section: section, amendment and issue dates, whether the change was substantive and whether the section was removed. Needs title and part.

Dated list of amendments to a CFR part or section: section, amendment and issue dates, whether the change was substantive and whether the section was removed. Tells a compliance team what changed and when. Oldest first, so pass issued_after on long-lived parts.

- Tool ID: `ecfr/change-history`
- Provider: [eCFR](/providers/ecfr.md)
- Capability: [Knowledge & research](/tools/knowledge.md)
- Price: no charge per call
- Authentication: an authorised Agentik workspace is required for execution, including zero-price tools.

## Pricing contract

No charge per call. A workspace is still needed so your agent can call it.


```json
{
  "model": "per_call",
  "amountUsd": 0
}
```

## Complete input schema


```json
{
  "type": "object",
  "properties": {
    "title": {
      "type": "integer",
      "minimum": 1,
      "maximum": 50,
      "description": "CFR title number, e.g. 16"
    },
    "part": {
      "type": "string",
      "pattern": "^[0-9A-Za-z]{1,10}$",
      "description": "CFR part, e.g. '312'"
    },
    "section": {
      "type": "string",
      "pattern": "^[0-9A-Za-z.-]{1,20}$",
      "description": "Section number, e.g. '312.5'"
    },
    "issued_after": {
      "type": "string",
      "pattern": "^[0-9]{4}-[0-9]{2}-[0-9]{2}$",
      "description": "Only changes issued on or after this date, e.g. '2020-01-01'"
    },
    "issued_before": {
      "type": "string",
      "pattern": "^[0-9]{4}-[0-9]{2}-[0-9]{2}$",
      "description": "Only changes issued on or before this date, e.g. '2025-12-31'"
    }
  },
  "required": [
    "title",
    "part"
  ],
  "additionalProperties": false
}
```

## Published example

This is the provider tool’s published example. Replace example values with the user’s requested inputs, respecting the schema; do not execute an example merely to test a connection.


```json
{
  "tool_id": "ecfr/change-history",
  "input": {
    "title": 16,
    "part": "312",
    "issued_after": "2020-01-01"
  }
}
```

## Execute and retrieve

Inspect again before execution, explain the price and obtain the required authority. Use MCP run_tool or POST /v1/run with this tool ID, valid input and an idempotency key. Save the returned run ID and follow the actual state. If Agentik answers that the tool is temporarily unavailable, do not retry it blindly; use discovery to propose an alternative.

A partial or uncertain result can still have consumed provider resources. Consult [billing](/docs/billing.md), [idempotency](/docs/idempotency.md) and [asynchronous results](/docs/async.md).

Licence: Public domain (U.S. Government work).

Attribution: Data from eCFR.gov (Office of the Federal Register, National Archives).

[Provider documentation](https://www.ecfr.gov/developers/documentation/api/v1)

[REST inspection](https://api.agentik.cc/v1/tools/ecfr/change-history) · [OpenAPI](/openapi.json) · [Connection guide](/connect.md)

---

[HTML page](/providers/ecfr/change-history) · [Agent index](/llms.txt)