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io.github.SolomonisBlack/tollbooth-x402

NPM · TOLLBOOTH-X402 · SCANNED SEP 22

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

Available components

0 this week 83 Trust /100
Trust breakdown (7 categories)

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. How we score → Why this is hard to score →

Supply Chain Security98
  • No malware found by supply-chain analysis.Pass
  • No known CVEs affecting this package version or its production dependencies.Pass
  • No install/post-install scripts declared.Pass
  • 31 of 96 dependencies flagged as unhealthy. View diagnostics → Partial
Provenance & Transparency45
Schema Quality & AI Usability79
  • AI-judged instruction clarity (excellent).Pass
  • Tool/resource definitions use about 1072 tokens (~107/item across 10 items; 10 tools + 0 resources), lean.Pass
  • Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management100
  • No destabilizing schema changes in the last 30 days.Pass
Tool Coverage100
  • 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
  • 100% of tool parameters carry a description.Pass
Tool Safety75
  • No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
  • 0 of 1 tool(s) whose name or description implies an irreversible operation declare an MCP destructiveHint annotation; "tollbooth_how_to_pay" implies "pay" and declares no destructiveHint at all, which the MCP spec reads as destructive by default. See how to fix → Fail
  • An AI judge read all 10 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
  • Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.Pass
Install

How do I install the io.github.SolomonisBlack/tollbooth-x402 MCP server?

io.github.SolomonisBlack/tollbooth-x402 runs locally as an npm package, launched with npx -y tollbooth-x402. Ready-made configuration for Claude, Cursor, VS Code, Codex and 5 more is on this page, copied from each client's own documentation.

npm · tollbooth-x402

# add to Claude Code
claude mcp add solomonisblack-tollbooth-x402 -- npx -y tollbooth-x402
// .cursor/mcp.json
{
  "mcpServers": {
    "solomonisblack-tollbooth-x402": {
      "command": "npx",
      "args": [
        "-y",
        "tollbooth-x402"
      ]
    }
  }
}
// .vscode/mcp.json
{
  "servers": {
    "solomonisblack-tollbooth-x402": {
      "command": "npx",
      "args": [
        "-y",
        "tollbooth-x402"
      ]
    }
  }
}
# add to Codex CLI
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
    }
  }
}
# add to OpenClaw
openclaw mcp add solomonisblack-tollbooth-x402 --command npx --arg -y --arg tollbooth-x402
# ~/.hermes/config.yaml
mcp_servers:
  solomonisblack-tollbooth-x402:
    command: "npx"
    args: ["-y", "tollbooth-x402"]
// ~/.netclaw/config/netclaw.json
{
  "McpServers": {
    "solomonisblack-tollbooth-x402": {
      "Transport": "stdio",
      "Command": "npx",
      "Arguments": [
        "-y",
        "tollbooth-x402"
      ]
    }
  }
}
# add to Vellum
assistant mcp add solomonisblack-tollbooth-x402 -t stdio -c npx -a -y tollbooth-x402
// mcp.json
{
  "mcpServers": {
    "solomonisblack-tollbooth-x402": {
      "command": "npx",
      "args": [
        "-y",
        "tollbooth-x402"
      ]
    }
  }
}
Changelog

Every change we have recorded for this component, newest first. Security-relevant changes are always shown. ▲ marks a change for the better, ▼ a change for the worse; unmarked changes are neutral.

  • 22 Sept 26 0
    • Stability: 0.97 → pass security
  • 21 Sept 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 93 to 97. That category is still filling its 30-day observation window: 28 days of observed history at the previous scan, 29 at this one. The score rises as the window fills, whether or not the server changes.

  • 19 Sept 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 87 to 90. That category is still filling its 30-day observation window: 26 days of observed history at the previous scan, 27 at this one. The score rises as the window fills, whether or not the server changes.

  • 17 Sept 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 80 to 83. That category is still filling its 30-day observation window: 24 days of observed history at the previous scan, 25 at this one. The score rises as the window fills, whether or not the server changes.

  • 16 Sept 26 −3
    • Stability: pass → 0.80 functional
  • 15 Sept 26 0
    • Stability: 0.97 → pass security
  • 14 Sept 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 93 to 97. That category is still filling its 30-day observation window: 28 days of observed history at the previous scan, 29 at this one. The score rises as the window fills, whether or not the server changes.

  • 12 Sept 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 87 to 90. That category is still filling its 30-day observation window: 26 days of observed history at the previous scan, 27 at this one. The score rises as the window fills, whether or not the server changes.

Diagnostics

Diagnostic detail from the automated scan of this channel: what the scanner observed at each step, so you can see exactly where a check passed or failed. It is informational only and never changes the trust score.

Captured 22 Sept 2026 · Analysed npm/tollbooth-x402@0.6.0

Provenance No attestation

The registry publishes no build provenance for this version, so there is nothing to verify.

Result No attestation
Ecosystem npm

Background: How many MCP packages publish verified provenance →

Dependencies 96 packages
Packages resolved 96
Stale 31
Tree resolution Complete

Background: SBOMs and build attestations, explained →

MCP tools · 10 exposed · ~1,072 tokens

The tools this component advertises to a client, with an estimated token cost for each. Expand a tool to see its parameters and schema. The per-tool counts are indicative and are not scored directly; the schema's total context footprint is one signal in Schema Quality & AI Usability. A tool's description is untrusted text the model reads on every call, which is what makes this list a security surface and not just an inventory: how tool poisoning works →

Tool Tokens
tollbooth_catalog ~61

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.

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

tollbooth_golden ~90

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.

NameTypeReqDescription
toolstringyesThe tool id, e.g. "social-security" (see tollbooth_catalog)

No output schema declared.

No examples provided.

tollbooth_gvp_check ~160

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.

NameTypeReqDescription
inputsobjectyesthe inputs that answer was computed from
responseobjectyesthe GVP answer object to check (must include its provenance block)

No output schema declared.

No examples provided.

tollbooth_how_to_pay ~51

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

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

tollbooth_preview ~106

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.

NameTypeReqDescription
inputsobjectyesTool inputs per the catalog inputSchema
toolstringyesThe tool id, e.g. "paycheck" (see tollbooth_catalog for ids)

No output schema declared.

No examples provided.

tollbooth_quote ~196

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.

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

No output schema declared.

No examples provided.

tollbooth_recommend ~74

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.

NameTypeReqDescription
querystringyesWhat you are trying to calculate, in plain English

No output schema declared.

No examples provided.

tollbooth_spec ~42

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.

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

tollbooth_verify ~213

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.

NameTypeReqDescription
claimthe claimed answer to check — an object of {field: value} pairs, or a scalar when `field` is given
fieldstringcheck a single field of the result
inputsobjectyesthe inputs the answer was computed from
tolerancenumbernumeric match tolerance (default 0.01)
toolstringyestool id, e.g. "paycheck"

No output schema declared.

No examples provided.

tollbooth_verify_hash ~79

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).

NameTypeReqDescription
inputsobjectyesThe exact inputs sent with that call
responseobjectyesThe full JSON response from a paid Tollbooth call

No output schema declared.

No examples provided.

Common questions

What is the io.github.SolomonisBlack/tollbooth-x402 MCP server?

io.github.SolomonisBlack/tollbooth-x402 is an MCP server listed in the public MCP registry as io.github.SolomonisBlack/tollbooth-x402. Discover, quote, verify & self-check 56 x402 pay-per-call finance/tax calculators for AI agents. This page covers its npm package (tollbooth-x402).

Is the io.github.SolomonisBlack/tollbooth-x402 MCP server safe to use?

io.github.SolomonisBlack/tollbooth-x402 scores 83 out of 100 on VerifyMCP. We found no known CVEs affecting it as of 22 September 2026. It declares no install or post-install scripts. 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 io.github.SolomonisBlack/tollbooth-x402 MCP server expose?

io.github.SolomonisBlack/tollbooth-x402 exposes 10 tools: tollbooth_catalog, tollbooth_preview, tollbooth_quote, tollbooth_recommend, tollbooth_golden, and 5 more. Their descriptions and schemas cost roughly 1,072 tokens of context every time the server is loaded.

Is the io.github.SolomonisBlack/tollbooth-x402 MCP server still maintained?

io.github.SolomonisBlack/tollbooth-x402 is still listed as active in the MCP registry. We last reached this channel on 22 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.

What licence is the io.github.SolomonisBlack/tollbooth-x402 MCP server under?

io.github.SolomonisBlack/tollbooth-x402 declares the MIT licence, which is OSI-approved. That covers the source only, and says nothing about the cost of any service it calls.