Build with C4C: the regulation library, in your own tools.

Your AI knows the gist. Your tools need the regulator’s exact words, with the citation, the version in force and a way to prove the quote is real. Pick the path that fits how you build; each takes a few minutes.

You areUseCost
Building an agent (Claude, OpenAI or any MCP client)1. The MCP server: one URL, no keyFree
Calling it from your own code or workflow2. The C4C API: REST, OpenAPI 3.1Free to evaluate
Running it in production, or near borrower data3. C4C Private: in your own environment, no outside connectionsFree to download; internal updates $399 a month

1. Agents: connect the MCP server

https://mcp.claudeforcompliance.com/mcp works with any client that speaks MCP over HTTP. No key, no sign-up. Your agent gets the same tools a person gets in their chat: search, read a section verbatim, resolve a citation, and check a quote.

Claude Agent SDK (TypeScript)

import { query } from "@anthropic-ai/claude-agent-sdk";

for await (const m of query({
  prompt: "What does 24 CFR 203.402 allow for hazard insurance? Quote it.",
  options: {
    mcpServers: { c4c: { type: "http", url: "https://mcp.claudeforcompliance.com/mcp" } },
    allowedTools: ["mcp__c4c"],
  },
})) {
  if (m.type === "result") console.log(m.result);
}

OpenAI Agents SDK (Python)

import asyncio
from agents import Agent, Runner
from agents.mcp import MCPServerStreamableHttp

async def main():
    async with MCPServerStreamableHttp(
        name="c4c", params={"url": "https://mcp.claudeforcompliance.com/mcp"}, cache_tools_list=True
    ) as c4c:
        agent = Agent(
            name="Compliance research",
            instructions="Quote the regulator's exact words with the citation. Check each quote with verify_quote.",
            mcp_servers=[c4c],
        )
        result = await Runner.run(agent, "What does 24 CFR 203.402 allow for hazard insurance?")
        print(result.final_output)

asyncio.run(main())

Claude Code

claude mcp add --transport http c4c https://mcp.claudeforcompliance.com/mcp

Other clients (Cursor, Copilot, ChatGPT and more): C4C MCP setup.

2. Your code: call the C4C API

The same tools over plain HTTPS: POST https://mcp.claudeforcompliance.com/v1/tools/<tool> with JSON arguments and Authorization: Bearer <key>. The OpenAPI 3.1 file needs no key and works with code generators and Postman. Get a free trial key: sign up with your work email, confirm the link, and the key is yours in about a minute.

Check a quote before it reaches a memo

verify_quote is the step most homegrown tools skip. Hand it the passage your model produced; it says whether the regulator actually wrote it. A real line from 24 CFR 203.402 comes back exact. A paraphrase does not:

curl -s https://mcp.claudeforcompliance.com/v1/tools/verify_quote \
  -H "Authorization: Bearer $C4C_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"text": "Hazard insurance premiums on the mortgaged property at any rate",
       "register_id": "fha-24cfr-203-402"}'
"outcome": "not_found",
"unsupported": ["at any rate"],
"differences": {
  "extra_in_quote": ["at any rate"],
  "closest_source": "Hazard insurance premiums on the mortgaged property"
},
"note": "... A dropped or added word (for example 'not') can reverse the meaning."

Full tool list, Python and JavaScript examples, errors and limits: C4C API docs.

3. Your environment: run C4C Private

Want the library inside your own stack, next to your own data and your own retrieval? Run C4C Private. It is the whole library behind a small read-only server in your network or AWS account. It never sees your documents, makes no outside connections once updates come through your own gate, and every release is signed.

git clone https://github.com/earl-hash/c4c-mcp-server.git
cd c4c-mcp-server
docker build -t c4c-mcp .
docker run -d --name c4c-mcp -p 8080:8080 -v c4c-data:/data \
  -e C4C_LICENSE_KEY=your-free-key \
  -e C4C_AUTH_TOKEN=choose-a-long-random-token \
  c4c-mcp
# then point any MCP client at http://<host>:8080/mcp
# with the header  Authorization: Bearer <C4C_AUTH_TOKEN>

Available in AWS Marketplace

What “formatted for AI” means here

Research and reference only, not legal advice; every result says so. The code is public under the Elastic License 2.0; the library is free for research and reference use under the C4C Library License. API use is subject to the API terms. Questions or a bigger plan: earl@cfsynergies.com.