ecfr-mcp

find_recent_changes

Read-only

Find CFR sections changed since a given date, removals included.

Instructions

Find CFR sections changed since a given date, removals included.

Built on eCFR's version history: every version issued on or after since_date, newest first. Each change says whether the section was amended, removed (change='removed'), or re-issued with no text change (substantive=false). 'summary' counts each kind. A section changed twice appears twice.

since_date must be in YYYY-MM-DD format. Filter with title (default 48), chapter (Title 48: 1 = FAR, 2 = DFARS, 99 = CAS) or part. per_page (default 100, max 5000) and page step through long lists; total_pages says how many pages there are.

Common pattern: find FAR changes since a specific date to check for regulatory updates that might affect ongoing acquisitions.

Input Schema

Name	Required	Description	Default
`page`	No
`part`	No
`title`	No
`chapter`	No
`per_page`	No
`since_date`	Yes

Output Schema

Name	Required	Description	Default
No arguments

Schema Changelog

Changes observed during successful MCP inspections.

Changed1 schema field changedv1.0.33Oct 12, 2026
- addedInput schema / properties / page
```
Added value: +{
+  "default": 1,
+  "title": "Page",
+  "type": "integer"
+}
```

Changed2 schema fields changedv1.0.7Aug 20, 2026

addedInput schema / properties / chapter / anyOf

Added value: +[
+  {
+    "type": "string"
+  },
+  {
+    "type": "integer"
+  },
+  {
+    "type": "null"
+  }
+]

addedInput schema / properties / part / anyOf

Added value: +[
+  {
+    "type": "string"
+  },
+  {
+    "type": "integer"
+  },
+  {
+    "type": "null"
+  }
+]

First observedv0.2.6May 16, 2026

TDQS

A4.7/5.0

Behavior5/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already carry the safety profile (readOnly, non-destructive), yet the description adds substantial behavior: removal vs amendment vs re-issue semantics, substantive=false for no-text-change, duplicate rows for twice-changed sections, summary counts, and pagination limits (per_page max 5000, total_pages). This is rich disclosure beyond the annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with purpose and change semantics, then parameters, then the common pattern – a sensible order. It is slightly padded by the line-break formatting and the redundant 'summary counts each kind' / 'appears twice' sentences, but nearly every line carries load.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With an output schema present the description needn't define return shape, and it still explains the meaningful fields (summary, total_pages) at the business-logic level. Combined with full parameter documentation, an agent has everything needed to invoke and interpret results.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0%, so the description carries the full burden and does so: since_date format (YYYY-MM-DD), title default 48, chapter mapping (1=FAR, 2=DFARS, 99=CAS), part, per_page default/max, and page. Every one of the six parameters gains meaning not present in the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource (+scope): 'Find CFR sections changed since a given date, removals included,' and immediately distinguishes itself via version-history semantics. An agent can tell this apart from get_version_history or compare_versions without opening a schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides a concrete usage context ('find FAR changes since a specific date to check for regulatory updates') and the default filters that make that pattern work. It does not explicitly name which sibling to use instead (e.g., get_version_history for a single section), so it is clear context without exclusions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server