Run the engine from inside Claude
A language model cannot run ten thousand correlated return paths, a Guyton-Klinger guardrail rule, or a tax-aware withdrawal order and be right about it. It can ask something that can. This connector gives Claude the same engine the app runs, so when you ask for a projection you get a computation with its assumptions attached rather than a plausible paragraph.
Connect it
In Claude, add a custom connector with this URL:
https://mcp.quantcalc.app
- Open Settings → Connectors in Claude.
- Choose Add custom connector.
- Paste the URL above and save.
No account and no signup. If you hold a QuantCalc PRO licence, supply the key as the connector's authorisation token and runs go to full precision. The key is held at the connection, never passed as part of the conversation.
What it can do
| Tool | What it returns |
|---|---|
run_retirement_projection |
Success rate, the ending-portfolio distribution, and the assumptions that produced them. |
compare_return_assumptions |
The same plan under each published capital market assumption set, so you can see how far the answer moves with the forecast used. |
list_return_assumption_sources |
Which assumption sets the engine carries and which components each publisher provides. |
explain_methodology |
What the engine models and what it deliberately leaves out. |
Every tool is read-only. Nothing is stored, and no client data is written anywhere.
What comes back with the number
A success rate is meaningless without the assumptions behind it, and an assistant summarising a result will drop a caveat it was not handed explicitly. So every result states, in the response itself:
- the return model that actually ran — reported by the engine, not by the request;
- the number of paths, and the real trial count behind the success rate;
- the income it assumed including when it assumed none, because an unstated Social Security figure moves a plan more than most inputs;
- whether a correlation matrix had to be adjusted before the run;
- a plain warning when a run is not precise enough to put in front of a client.
Limits
Without a licence, runs use 2,000 paths — enough that the 95% interval around a success rate is roughly a point and a half wide, which is a figure you can reason with. A PRO licence raises that to 10,000 paths, and unlocks the portfolio optimizer, glide paths, custom capital market assumptions and multi-period planning, none of which the free connector exposes.
QuantCalc is calculation software, not financial advice. What the engine models and what it deliberately leaves out — AMT, the 199A deduction, NUA and estate tax among them — is written down in the tax methodology and the full methodology.
Support
Questions, or something not behaving: [email protected]. Data handling is covered by the privacy policy.