401k.loans: 401(k) loan and withdrawal calculators

loans.401k/401k-loans401k.loansstreamable-httpv1.2026.1101.1Scanned 5 hours ago

401(k) loan true cost, loan vs. withdrawal vs. personal loan vs. HELOC, early withdrawal tax.

3 tools: 1 do something that can't be undone, 1 change things and 1 only read.

Reads private data · 0
Reads text others write · 0
Can send data out · 0
2 findings

Tools listed without sign-in. Remote posture

Anlyon alternative

2 of these tools change something. Run those as governed actions.

Declare what an action changes, and Anlyon puts it under a shared limit, binds every approval to the exact request, and grades the outcome. It works on any HTTPS API you can describe as an action.

Anlyon does not run, proxy or govern this MCP server. A tool your own code calls directly is not routed through Anlyon and is not governed by it.

Import an OpenAPI spec →

Tools

Grouped by what each tool does, most consequential first. Open one for its reasons and full description; descriptions are the publisher's own words.

3 tools

Can't be undone 1Sends, pays, publishes or merges: once done, it cannot be taken back.Claude Code: ask

calculate_401k_early_withdrawalRuns the 401k.loans early withdrawal calculator for a cash-out or hardship withdrawal: amount taken out (or the gross needed to net a target), income tax at your marginal rates, th…1 finding
Why it is in this group
- The name "calculate_401k_early_withdrawal" says "withdrawal": a word that usually means money moves, which cannot be taken back.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- Warn
  The server marks "calculate_401k_early_withdrawal" read-only (readOnlyHint: true), and its own name, description or input give the class "irreversible".
  Matched text
  annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":false}; The name "calculate_401k_early_withdrawal" says "withdrawal": a word that usually means money moves, which cannot be taken back.
  What this check looks for
Description, as the server wrote it
Runs the 401k.loans early withdrawal calculator for a cash-out or hardship withdrawal: amount taken out (or the gross needed to net a target), income tax at your marginal rates, the 10% additional tax, what you keep, what the plan withholds up front (20% mandatory, or 10% default for hardship), the check amount, and the balance due or refund at filing.
Annotations the server declares
- title: 401(k) early withdrawal tax and penalty
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false

Changes things 1Creates or changes something that can be changed back.Claude Code: ask

calculate_401k_loan_costRuns the 401k.loans true-cost calculator: payment per paycheck and number of payments, total repaid and interest, pre-tax pay needed per payment, tax later on the interest, the 401…1 finding
Why it is in this group
- The description's first verb is "run": a word for a change.
- The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
Findings
- Warn
  The server marks "calculate_401k_loan_cost" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
  Matched text
  annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":false}; The description's first verb is "run": a word for a change.
  What this check looks for
Description, as the server wrote it
Runs the 401k.loans true-cost calculator: payment per paycheck and number of payments, total repaid and interest, pre-tax pay needed per payment, tax later on the interest, the 401(k) balance at payoff with and without the loan (growth gap) and that gap at 65, the legal and usual plan borrowing limits, and, if you might leave the job, the balance owed then plus the tax and 10% additional tax if it is not repaid or rolled over.
Annotations the server declares
- title: True cost of a 401(k) loan
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false

Only reads 1Looks things up and changes nothing.Show 1 read-only tool

compare_401k_loan_alternativesPrices four ways to raise the same cash with the 401k.loans comparison tool: 401(k) loan, hardship withdrawal (grossed up for tax and the 10% additional tax), personal loan (rate p…No findings
Why it is in this group
- The name "compare_401k_loan_alternatives" says "compare": a word for reading.
Description, as the server wrote it
Prices four ways to raise the same cash with the 401k.loans comparison tool: 401(k) loan, hardship withdrawal (grossed up for tax and the 10% additional tax), personal loan (rate plus origination fee) and HELOC. For each: amount taken out, monthly payment, money gone for good (interest to others, fees, tax, penalty), interest paid back to yourself, how much smaller the 401(k) is at term end and at 65, and whether it is allowed.
Annotations the server declares
- title: Compare a 401(k) loan with a hardship withdrawal, personal loan and HELOC
- readOnlyHint: true
- destructiveHint: false
- idempotentHint: true
- openWorldHint: false

This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.

Exfil surface

Which tools read private data, which read text someone else can write, and which can send data out. One of each is a path a prompt injection can use.

No private-data, untrusted-input, outbound path in this server alone: no tool is tagged private-data or untrusted-input or outbound.

Reads private data0: Reads files, mail, messages, databases, secrets, calendars or repositories.
Reads text others write0: Brings in text someone else can write: web pages, inbound email, messages, issues and comments.
Can send data out0: Can carry data to people or systems: it sends, posts or publishes, or takes a recipient, channel or URL.

Other servers in the same agent add their own tools to these paths. Audit your whole setup to see them together.

Remote posture

What anyone on the internet sees at the remote endpoint: an anonymous initialize and tools/list, and the public OAuth metadata.

Tools listed without sign-in

Looked at Nov 2, 2026, 00:20 UTC, unchanged since Nov 2, 2026. No credentials were sent and no tool was called. What is looked at.

Reachable: yes
HTTP status of an anonymous initialize: 200
tools/list served without credentials: yes
Tools that change things, listed without credentials: 2
Protocol version: 2025-06-18
WWW-Authenticate on 401: not observed
resource_metadata in WWW-Authenticate: not observed
RFC 9728 protected resource metadata: not observed
Authorization servers: not observed
Legacy HTTP+SSE transport: no
Dynamic client registration: not observed
Client ID metadata documents: not observed

HighThe whole server
The endpoint served tools/list without credentials, and the list has 2 tools that change things (1 irreversible, 1 write). Whether a call also works without credentials was not tested: tools are never called.
Matched text
https://401k.loans/mcp: tools/list returned 3 tools to an anonymous client, including calculate_401k_early_withdrawal (irreversible), calculate_401k_loan_cost (write)
What this check looks for

Findings

Matches of fixed checks, with the text they matched.

2 warn

Warncalculate_401k_loan_cost
The server marks "calculate_401k_loan_cost" read-only (readOnlyHint: true), and its own name, description or input give the class "write".
Matched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":false}; The description's first verb is "run": a word for a change.
What this check looks for
Warncalculate_401k_early_withdrawal
The server marks "calculate_401k_early_withdrawal" read-only (readOnlyHint: true), and its own name, description or input give the class "irreversible".
Matched text
annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":false}; The name "calculate_401k_early_withdrawal" says "withdrawal": a word that usually means money moves, which cannot be taken back.
What this check looks for

History

Changes to its tool definitions and to its remote endpoint, newest first.

No change seen yet. Its tools are rescanned every day, and a remote endpoint is looked at once a week.

All changes to this server

Install

Pinned to version 1.2026.1101.1. Values in angle brackets are yours to fill in.

claude mcp add --transport http 401k-loans https://401k.loans/mcp

claude mcp add --transport http 401k-loans https://401k.loans/mcp

Run in a terminal.

Claude Code permissions

Allow the reads, ask before a change or a way out, deny the deletes. Paste into .claude/settings.json.

.claude/settings.json

{
  "permissions": {
    "allow": [
      "mcp__401k-loans__compare_401k_loan_alternatives"
    ],
    "ask": [
      "mcp__401k-loans__calculate_401k_loan_cost",
      "mcp__401k-loans__calculate_401k_early_withdrawal"
    ],
    "deny": []
  }
}

Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. A read that can send data out (it takes a URL, say) asks first too. It assumes the server is installed as 401k-loans. Review it before you use it.

Keep the decision: fail CI when the tools change, follow every change, or show a badge.

Pin in CI

Fail a build when the tools you reviewed are not the tools the server serves today.

curl -s "https://anlyon.dev/api/v1/servers/loans.401k/401k-loans/verify?hash=5a92a387356d9264332cb0b1d8b2a78a210c9f5345c69a835981829dddfaea75" | jq -e '.changed == false'

Pinned hash 5a92a387356d, from Nov 1, 2026, 22:18 UTC.

Watch

Get told when its tools change: a new tool, a new description, a new class.

https://anlyon.dev/servers/loans.401k/401k-loans/changes.xml

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Badge

[![anlyon.dev](https://anlyon.dev/badge/loans.401k/401k-loans.svg)](https://anlyon.dev/servers/loans.401k/401k-loans)

Source: MCP Registry. Synced Nov 1, 2026, 23:18 UTC.