Cal puts 166 wholesale lenders, 1,400+ indexed program documents, and 1,300+ down-payment-assistance programs into Claude Desktop, Cursor, Continue, or any MCP-compatible AI assistant. Built by a 20-year mortgage broker for working LOs.
A mortgage MCP wrapper is mechanical to build, anyone can write the eight tool schemas in an afternoon. The hard part is the library behind them: matrix PDFs scraped from broker-gated portals, lender intel built from real wholesale relationships, DPA programs verified against state housing-finance-agency websites. Six months of curation. A competitor cloning the wrapper gets an empty shell that hallucinates. Cal is what makes it answer.
When you install Cal in your MCP client, your AI assistant gets a slash menu with these eight tools. Ask any mortgage question in plain English; Claude (or whichever model) picks the right tool and Cal's library answers.
FHFA conforming loan limits, FHA loan limits, VA funding fee, FHA MIP, agency DTI caps. County-level. 50 states + DC.
Scenario-aware wholesale lender finder. FICO + LTV + loan amount + state + occupancy → ranked top 5 with score, qualifying reasons, and blockers.
Full record for one lender: programs, state licenses, AE contact, broker portal URL, status, recent matrix dates.
Indexed matrices, handbooks, overlays for a lender. Sorted master → current → superseded with extracted summaries.
Down-payment-assistance programs by state, county, city, FTHB status, and program type. Up to 25 ranked programs with provider URLs.
Tribal-knowledge intel: strengths, watch-outs, speed notes, scenarios they love, scenarios to avoid, AE contacts. Pass intent to narrow.
Structuring playbooks for hard mortgage scenarios: departing residence, ITIN / foreign national, sub-580 FHA, renovation, super-jumbo, plus the matrix-freshness citation rule. Each pattern returns the recommended lender shortlist with the specific guideline to apply.
ValueGuard comparable-sales valuation. Pass a subject property and 4+ comps; returns an indicated market value, a floor and ceiling range, an over or under-priced verdict, a confidence level, and the comps used.
Real Q&A from production, May 9, 2026. Citations are pulled from FNMA Selling Guide §B3-5.3-07 and FHA Handbook 4000.1 §II.A.4.b.iii, both with current effective dates.
Fannie Mae conventional: 4 years from the discharge or dismissal date FNMA B3-5.3-07. Reduced to 2 years with documented extenuating circumstances.
FHA: 2 years from the discharge date FHA 4000.1 II.A.4.b.iii. Borrower must demonstrate re-established credit and that the bankruptcy cause was beyond their control.
Key takeaway: FHA is significantly more lenient, 2 years standard vs. 4 years for conventional. For borrowers 2-4 years post Ch7 discharge, FHA is likely their only agency option until they hit the 4-year mark for conventional eligibility.
Sources: [1] FHA 4000.1, Bankruptcy Waiting Periods · eff. 2024-09-26 · [2] FNMA Selling Guide §B3-5.3-07 · eff. 2019-08-07
All paths use the same long-lived API key. Get yours at askcal.io (broker LOs auto-approved).
The server is live on public npm as @askcal/mcp-server v0.2.0, MIT-licensed, running against the Cal API. Install in one line, no clone required.
npx -y @askcal/mcp-server
Then point any MCP client at it with your API key:
{
"mcpServers": {
"cal": {
"command": "npx",
"args": ["-y", "@askcal/mcp-server"],
"env": { "CAL_API_TOKEN": "cal_live_…" }
}
}
}
Prefer to clone and build? That path still works:
git clone https://github.com/askcal/cal-mcp-server.git cd cal-mcp-server npm install npm run build npm run smoke # end-to-end test against the live API npm run build:dxt # optional: produces artifacts/cal-mcp-server-X.dxt
After the clone + build above, point your client at the built server. Same shape across clients (Cursor: Settings → MCP, Continue: ~/.continue/config.json).
{
"mcpServers": {
"cal": {
"command": "node",
"args": ["/path/to/cal-mcp-server/dist/index.js"],
"env": {
"CAL_API_TOKEN": "cal_live_…"
}
}
}
}
Live now: npx -y @askcal/mcp-server
A signed .dxt bundle for one-click Claude Desktop install is on the way. Today you can generate it yourself from the clone: run npm run build:dxt (Clone + build tab) to produce artifacts/cal-mcp-server-X.dxt, then drag it onto Claude Desktop's Settings → Extensions. It prompts for your Cal API key (stored in the macOS Keychain, never plaintext) and is ready on next launch.
# Get a long-lived API key first curl -X POST https://api.askcal.io/auth/api-keys \ -H "Authorization: Bearer $SESSION" \ -d '{"label":"my-claude-desktop"}'
v0.1 puts Cal in your AI assistant. v0.2-0.3 puts your AI assistant inside Cal, an agent that pulls live rate sheets, runs qualifying math against the top three lenders, drafts the comparison letter, schedules the follow-up call, and pushes structured loan summaries to the CRM. From a single LO prompt. While the LO is on the phone with the family.
In parallel, we're open-sourcing MCP wrappers for the public agency rulebooks (Fannie Selling Guide, Freddie Guide, FHA Handbook 4000.1, VA Lender's Handbook, FHFA limits, HUD AMI). Cal becomes the maintainer of the mortgage MCP layer.