# io.github.SolomonisBlack/tollbooth-x402 (npm · tollbooth-x402)

Discover, quote, verify & self-check 56 x402 pay-per-call finance/tax calculators for AI agents.

- Trust score: 68/100 (medium)
- Change this week: +22
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-08-03

## Components

- npm · `tollbooth-x402`: 68/100 (this document), [markdown](https://verifymcp.io/servers/solomonisblack-tollbooth-x402/tollbooth-x402.md), [page](https://verifymcp.io/servers/solomonisblack-tollbooth-x402/tollbooth-x402)

## Channel facts

- Registry: `npm`
- Package: `tollbooth-x402`
- Version: `0.6.0`
- Transport: `stdio`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically from public evidence about the published package, including repeated runs of it in an isolated sandbox, 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 2026-08-03.

- **Supply Chain Security**: 87/100
  - No malware found by supply-chain analysis.
  - Only part of the dependency tree could be resolved (95 of 99), so this covers what we could see, not the whole tree.
  - No install/post-install scripts declared.
  - Only part of the dependency tree could be resolved (95 of 99), so this covers what we could see, not the whole tree.
- **Provenance & Transparency**: 45/100
  - Source repository is publicly reachable at the declared URL.
  - Provenance check failed: no build-provenance attestation is published.
  - Clear OSI-approved license (MIT).
  - Actively maintained (last published 15 days ago).
  - Disclosure check failed: no security disclosure policy was found in the source repository.
- **Schema Quality & AI Usability**: 71/100
  - AI-judged instruction clarity (good).
  - Tool/resource definitions use about 1072 tokens (~107/item across 10 items; 10 tools + 0 resources), lean.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 27/100
  - Stability observed for 8 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.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.

## Install

### Claude

```bash
claude mcp add solomonisblack-tollbooth-x402 -- npx -y tollbooth-x402
```

### Codex

```bash
codex mcp add solomonisblack-tollbooth-x402 -- npx -y tollbooth-x402
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "solomonisblack-tollbooth-x402": {
      "type": "local",
      "command": [
        "npx",
        "-y",
        "tollbooth-x402"
      ],
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add solomonisblack-tollbooth-x402 --command npx --arg -y --arg tollbooth-x402
```

### Hermes

```yaml
mcp_servers:
  solomonisblack-tollbooth-x402:
    command: "npx"
    args: ["-y", "tollbooth-x402"]
```

### Other

```json
{
  "mcpServers": {
    "solomonisblack-tollbooth-x402": {
      "command": "npx",
      "args": [
        "-y",
        "tollbooth-x402"
      ]
    }
  }
}
```

## 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.

### 2026-08-02 (score 68, +47)

- [security regression] Provenance: unverified → fail
- [security improvement] Install scripts: unverified → pass
- [security improvement] Known CVEs: unverified → partial
- [security improvement] Malware scan: unverified → pass
- [functional regression] Security disclosure: fail → unverified
- [functional regression] Tool coverage: 100 → unverified
- [functional improvement] License: unverified → pass
- [functional improvement] Dependency health: unverified → partial
- [functional improvement] Maintenance: unverified → pass
- [functional improvement] MCP protocol: unverified → pass
- [functional improvement] Stability: unverified → 0.23
- [functional improvement] Schema quality: unverified → good
- [functional] Licence: MIT

### 2026-08-01 (score 21, +16)

- [functional improvement] Tool coverage: unverified → 100

### 2026-07-31 (score 5, −23)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-30 (score 28, −18)

- [security regression] Malware scan: pass → unverified

### 2026-07-27 (score 46)

First indexed and scored.

## MCP tools (10)

### `tollbooth_catalog` (~61 tokens)

List every Tollbooth paid endpoint at x402toll.com — verified calculators for tax, crypto/DeFi, lending, real estate, retirement, and business — with x402 prices, input schemas, methods, and golden-vector evidence. Free.

### `tollbooth_preview` (~106 tokens)

Free coarse preview of a Tollbooth tool (rounded headline figure only; the paid endpoint returns the full verified breakdown). Previewable tools include paycheck, self-employment-tax, capital-gains-tax, mortgage-affordability, llc-cost, debt-plan, impermanent-loss.

Input parameters:

- `inputs` (object, required): Tool inputs per the catalog inputSchema
- `tool` (string, required): The tool id, e.g. "paycheck" (see tollbooth_catalog for ids)

### `tollbooth_quote` (~196 tokens)

See the exact price AND the response shape BEFORE you pay. Give a tool id (e.g. "paycheck", see tollbooth_catalog) or a full paid path ("/v1/paycheck") and this decodes the endpoint's HTTP 402 x402 challenge — returning the amount in USDC atomic units + USD, asset, network, payTo, timeout, the resource URL, and (when discoverable) example input + paid-response shape. Nothing is spent. Call this first so you know the price and output structure before committing to pay. Free.

Input parameters:

- `inputs` (object): Optional inputs to probe with (defaults to {}); the price is per-call and does not depend on them
- `tool` (string, required): The tool id, e.g. "paycheck" (see tollbooth_catalog for ids), OR a full paid path starting with "/", e.g. "/v1/paycheck"

### `tollbooth_recommend` (~74 tokens)

Given a plain-English need (e.g. "how much tax on my bonus", "required minimum distribution"), returns the Tollbooth tools most likely to answer it, ranked, with their x402 prices and URLs. Free.

Input parameters:

- `query` (string, required): What you are trying to calculate, in plain English

### `tollbooth_golden` (~90 tokens)

Free verifiability check: returns a tool's published golden vector — for most tools, machine-checkable {sampleInputs, expectedResult, expectedResponseHash}. POST the sampleInputs to the paid endpoint and confirm the result + hash match to verify our math without trusting us.

Input parameters:

- `tool` (string, required): The tool id, e.g. "social-security" (see tollbooth_catalog)

### `tollbooth_verify_hash` (~79 tokens)

Free provenance check: re-derives the SHA-256 response hash of a previous Tollbooth paid response from its inputs and reports whether it matches (detects tampering).

Input parameters:

- `inputs` (object, required): The exact inputs sent with that call
- `response` (object, required): The full JSON response from a paid Tollbooth call

### `tollbooth_verify` (~213 tokens)

Confirm or deny a claimed answer — from ANY source (another model, a spreadsheet, a competitor) — against Tollbooth's verified engine, for free. It returns ONLY whether the claim matches and which field NAMES were wrong; it NEVER reveals the correct value, so you can check a number you got elsewhere without getting the answer for free. Pass the same inputs the answer was computed from plus the claimed answer (an object of {field: value}, or a scalar with `field` set). Use tollbooth_catalog for tool ids and input shapes.

Input parameters:

- `claim`: the claimed answer to check — an object of {field: value} pairs, or a scalar when `field` is given
- `field` (string): check a single field of the result
- `inputs` (object, required): the inputs the answer was computed from
- `tolerance` (number): numeric match tolerance (default 0.01)
- `tool` (string, required): tool id, e.g. "paycheck"

### `tollbooth_gvp_check` (~160 tokens)

Neutral Golden-Vector Provenance check for ANY service's answer (not just Tollbooth's). Pass a GVP response object plus the inputs it was computed from; this recomputes the response's OWN sha256 over {endpoint, inputs, result, method, dataVintage} and reports whether it is self-consistent and GVP-1 complete (formula trace + data vintage + reproducible hash), with a "self-consistent · reproducible" badge (NOT an endorsement). Proves reproducibility, not that the underlying data source is authoritative. Free.

Input parameters:

- `inputs` (object, required): the inputs that answer was computed from
- `response` (object, required): the GVP answer object to check (must include its provenance block)

### `tollbooth_spec` (~42 tokens)

The open provenance standard Tollbooth implements and authors — the rules a verified-computation service follows so agents can trust and re-derive its answers. Free.

### `tollbooth_how_to_pay` (~51 tokens)

How an agent pays a Tollbooth endpoint with x402 (v2) on Base: the 402 flow, the PAYMENT-SIGNATURE header, and client library pointers. Free.

## Diagnostics

Captured diagnostic sections: Provenance, Dependencies. The full working is on the page: https://verifymcp.io/servers/solomonisblack-tollbooth-x402/tollbooth-x402#diagnostics

## Score history

- 2026-08-03: 68
- 2026-08-02: 68
- 2026-08-01: 21
- 2026-07-31: 5
- 2026-07-30: 28
- 2026-07-28: 46
- 2026-07-27: 46

## Links

- npm package: https://www.npmjs.com/package/tollbooth-x402
- Socket report: https://socket.dev/npm/package/tollbooth-x402
- Repository: https://github.com/SolomonisBlack/tollbooth-x402
- Website: https://x402toll.com/
- Changelog RSS feed: https://verifymcp.io/servers/solomonisblack-tollbooth-x402/tollbooth-x402/changelog.xml
- Changelog JSON feed: https://verifymcp.io/servers/solomonisblack-tollbooth-x402/tollbooth-x402/changelog.json
- HTML version of this page: https://verifymcp.io/servers/solomonisblack-tollbooth-x402/tollbooth-x402