# Pass-through tax rules (remote · pass-through-tax-rules.vercel.app)

Cited, tax-year-dated rules for state PTET, the federal SALT cap, and bonus-depreciation conformity.

- Trust score: 78/100 (medium)
- Change this week: +3
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-11-05

## Components

- remote · `pass-through-tax-rules.vercel.app`: 78/100 (this document), [markdown](https://verifymcp.io/servers/app-vercel-pass-through-tax-rules-pass-through-tax-rules/api-mcp.md), [page](https://verifymcp.io/servers/app-vercel-pass-through-tax-rules-pass-through-tax-rules/api-mcp)

## Channel facts

- Endpoint: `https://pass-through-tax-rules.vercel.app/api/mcp`
- Transports: `streamable-http`
- Auth: `none`
- Version: `0.1.0`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-11-05.

- **Endpoint Security**: 80/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - No authorisation is required to call this server. Nothing on it is marked destructive, but we can't show that an anonymous caller can only read: full credit needs the server to list at least one tool and every tool to be verifiably read-only. We use a best-effort check of tool names and descriptions to tell read-only tools from tools that change things, so some genuinely read-only tools may not get full credit. Names that start with a read verb (get, list, read, search and similar) and accurate readOnlyHint annotations help. Meet that to earn full credit, or require authorisation.
  - HTTPS is enforced; there's no plaintext access path.
  - The HSTS (Strict-Transport-Security) header is present.
  - DNSSEC check failed: this domain isn't protected by DNSSEC.
- **Transport & Reachability**: 100/100
  - Verified streamable-http transport via a live MCP handshake.
- **Schema Quality & AI Usability**: 68/100
  - AI-judged instruction clarity (good).
  - Context-footprint check failed: tool/resource definitions use about 545 tokens (~136/item across 4 items; 4 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 40/100
  - Stability observed for 12 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - We read all 4 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 5 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 100/100
  - Implements a current MCP spec version (2026-07-28).

## Install

### How do I install the Pass-through tax rules MCP server?

Pass-through tax rules is a hosted endpoint at https://pass-through-tax-rules.vercel.app/api/mcp, so there is nothing to install locally. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

### Claude

```bash
claude mcp add --transport http app-vercel-pass-through-tax-rules-pass-through-t 'https://pass-through-tax-rules.vercel.app/api/mcp'
```

### Cursor

```json
{
  "mcpServers": {
    "app-vercel-pass-through-tax-rules-pass-through-t": {
      "url": "https://pass-through-tax-rules.vercel.app/api/mcp"
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "app-vercel-pass-through-tax-rules-pass-through-t": {
      "type": "http",
      "url": "https://pass-through-tax-rules.vercel.app/api/mcp"
    }
  }
}
```

### Codex

```toml
[mcp_servers.app-vercel-pass-through-tax-rules-pass-through-t]
url = "https://pass-through-tax-rules.vercel.app/api/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "app-vercel-pass-through-tax-rules-pass-through-t": {
      "type": "remote",
      "url": "https://pass-through-tax-rules.vercel.app/api/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add app-vercel-pass-through-tax-rules-pass-through-t --url 'https://pass-through-tax-rules.vercel.app/api/mcp' --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  app-vercel-pass-through-tax-rules-pass-through-t:
    url: "https://pass-through-tax-rules.vercel.app/api/mcp"
```

### Netclaw

```json
{
  "McpServers": {
    "app-vercel-pass-through-tax-rules-pass-through-t": {
      "Transport": "http",
      "Url": "https://pass-through-tax-rules.vercel.app/api/mcp"
    }
  }
}
```

### Vellum

```bash
assistant mcp add app-vercel-pass-through-tax-rules-pass-through-t -t streamable-http -u 'https://pass-through-tax-rules.vercel.app/api/mcp'
```

### Other

```json
{
  "mcpServers": {
    "app-vercel-pass-through-tax-rules-pass-through-t": {
      "type": "http",
      "url": "https://pass-through-tax-rules.vercel.app/api/mcp"
    }
  }
}
```

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-11-05 (score 78, +1)

No change was recorded against any check on this day. Stability & Change Management went from 37 to 40. That category is still filling its 30-day observation window: 11 days of observed history at the previous scan, 12 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-11-03 (score 77, +1)

No change was recorded against any check on this day. Stability & Change Management went from 30 to 33. That category is still filling its 30-day observation window: 9 days of observed history at the previous scan, 10 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-11-01 (score 76, +1)

No change was recorded against any check on this day. Stability & Change Management went from 23 to 27. That category is still filling its 30-day observation window: 7 days of observed history at the previous scan, 8 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-29 (score 75, +1)

No change was recorded against any check on this day. Stability & Change Management went from 13 to 17. That category is still filling its 30-day observation window: 4 days of observed history at the previous scan, 5 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-27 (score 74, +1)

No change was recorded against any check on this day. Stability & Change Management went from 7 to 10. That category is still filling its 30-day observation window: 2 days of observed history at the previous scan, 3 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-25 (score 73, 0)

- [security] Tool “coverage” rewrote its description, which is the text the model reads
- [functional improvement] Stability: unverified → 0.03
- [functional] Server version: 0.1.0 → 0.2.0
- [cosmetic] “bonus_conformity” reworded the description of “state”
- [cosmetic] “bonus_conformity” reworded the description of “tax_year”
- [cosmetic] “ptet_rules” reworded the description of “state”
- [cosmetic] “ptet_rules” reworded the description of “tax_year”

### 2026-10-24 (score 73)

First indexed and scored.

## MCP tools (4)

### `ptet_rules` (~109 tokens)

Pass-through entity tax

Elective pass-through entity tax for one state and tax year: eligibility, who elects, deadline, rate, owner credit or exclusion, estimates, and sunset. Returns not_covered when this server has no file. Informational, not tax advice.

Input parameters:

- `state` (string, required): Postal code or full state name. The District of Columbia is DC. New York City is NYC.
- `tax_year` (number|string, required): Tax year, such as 2026. Files are tax-year specific.

### `salt_cap` (~208 tokens)

Federal SALT cap

Compute the federal SALT deduction cap under 26 USC 164(b)(6) and (b)(7) for a tax year, filing status, and modified adjusted gross income. Returns the cap and the steps, not the deduction. Years before 2018 are not_covered. MAGI is used to compute and is not written to the usage log.

Input parameters:

- `filing_status` (string, required): single, married_filing_jointly, married_filing_separately, head_of_household, or qualifying_surviving_spouse. Aliases: mfj, mfs, hoh, qss.
- `magi` (number|string, required): Modified adjusted gross income: AGI plus IRC 911, 931, and 933 exclusions. Integer or decimal string, at most 8 decimal places.
- `tax_year` (number|string, required): Tax year. 2018 through 2024 use the prior flat cap. 2025 and later use section 164(b)(7).

### `bonus_conformity` (~110 tokens)

Bonus depreciation conformity

Whether a state conforms to IRC 168(k) bonus depreciation and IRC 179 for a tax year, its IRC conformity date, and the add-back or subtraction in plain terms. Unverified fields are null. Unknown states and years are not_covered.

Input parameters:

- `state` (string, required): Postal code or full state name. The District of Columbia is DC. New York City is NYC.
- `tax_year` (number|string, required): Tax year, such as 2026. Files are tax-year specific.

### `coverage` (~63 tokens)

Coverage

List jurisdictions and tax years in this dataset. elective_ptet_2026 counts only 2026 files with an elective PTET. no_elective_ptet_2026 and not_effective_2026 are separate and are not PTET states for 2026.

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/app-vercel-pass-through-tax-rules-pass-through-tax-rules/api-mcp#diagnostics

## Score history

- 2026-11-05: 78
- 2026-11-04: 77
- 2026-11-03: 77
- 2026-11-02: 76
- 2026-11-01: 76
- 2026-10-31: 75
- 2026-10-30: 75
- 2026-10-29: 75
- 2026-10-28: 74
- 2026-10-27: 74
- 2026-10-26: 73
- 2026-10-25: 73
- 2026-10-24: 73

## Common questions

### What is the Pass-through tax rules MCP server?

Pass-through tax rules is an MCP server listed in the public MCP registry as app.vercel.pass-through-tax-rules/pass-through-tax-rules. Cited, tax-year-dated rules for state PTET, the federal SALT cap, and bonus-depreciation conformity. This page covers its hosted endpoint (https://pass-through-tax-rules.vercel.app/api/mcp).

### Is the Pass-through tax rules MCP server safe to use?

Pass-through tax rules scores 78 out of 100 on VerifyMCP. That is a record of what we were able to check automatically, not an endorsement. The category breakdown on this page shows every signal behind the number, including the ones we could not confirm.

### What tools does the Pass-through tax rules MCP server expose?

Pass-through tax rules exposes 4 tools: ptet_rules, salt_cap, bonus_conformity, coverage. Their descriptions and schemas cost roughly 490 tokens of context every time the server is loaded.

### Does the Pass-through tax rules MCP server require authentication?

No. We connected to Pass-through tax rules without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.

### Is the Pass-through tax rules MCP server still maintained?

Pass-through tax rules is still listed as active in the MCP registry. We last reached this channel on 5 November 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

### What did VerifyMCP test on the Pass-through tax rules MCP server?

VerifyMCP ran 13 checks on Pass-through tax rules, covering TLS certificate, Authorization, HTTPS, HSTS header and 9 more. Supply Chain Security and Provenance & Transparency do not apply to a hosted endpoint, so they were not tested. The score does not measure everything, and the scoring documentation lists what it leaves out.

## Links

- Remote endpoint: https://pass-through-tax-rules.vercel.app/api/mcp
- Website: https://pass-through-tax-rules.vercel.app/
- Changelog RSS feed: https://verifymcp.io/servers/app-vercel-pass-through-tax-rules-pass-through-tax-rules/api-mcp.xml
- Changelog JSON feed: https://verifymcp.io/servers/app-vercel-pass-through-tax-rules-pass-through-tax-rules/api-mcp/changelog.json
- Trust report (JSON): https://verifymcp.io/servers/app-vercel-pass-through-tax-rules-pass-through-tax-rules/api-mcp.json
- HTML version of this page: https://verifymcp.io/servers/app-vercel-pass-through-tax-rules-pass-through-tax-rules/api-mcp