# fourzerotwo (remote · fourzerotwo.si)

400+ data APIs for agents: UK companies, property, trade, tenders, recalls, sanctions. Free tier

- Trust score: 86/100 (high trust)
- Change this week: +4
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-11-05

## Components

- remote · `fourzerotwo.si`: 86/100 (this document), [markdown](https://verifymcp.io/servers/si-fourzerotwo-data/fourzerotwo.md), [page](https://verifymcp.io/servers/si-fourzerotwo-data/fourzerotwo)

## Channel facts

- Endpoint: `https://fourzerotwo.si/mcp`
- Transports: `streamable-http`
- Auth: `none`
- Version: `1.2.1`

## 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. Every tool declares its destructiveHint and none is destructive, so open access doesn't expose one.
  - 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**: 80/100
  - 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).
  - AI-judged instruction clarity (good).
  - Context-footprint check failed: tool/resource definitions use about 635 tokens (~127/item across 5 items; 3 tools + 2 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 80/100
  - Stability observed for 24 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.
  - Structured output schemas are declared (100% of tools); any adoption earns full credit.
- **Tool Safety**: 100/100
  - No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.
  - We read all 3 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 supported MCP spec version (2025-11-25); the latest is 2026-07-28.

## Install

### How do I install the fourzerotwo MCP server?

fourzerotwo is a hosted endpoint at https://fourzerotwo.si/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 si-fourzerotwo-data 'https://fourzerotwo.si/mcp'
```

### Cursor

```json
{
  "mcpServers": {
    "si-fourzerotwo-data": {
      "url": "https://fourzerotwo.si/mcp"
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "si-fourzerotwo-data": {
      "type": "http",
      "url": "https://fourzerotwo.si/mcp"
    }
  }
}
```

### Codex

```toml
[mcp_servers.si-fourzerotwo-data]
url = "https://fourzerotwo.si/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "si-fourzerotwo-data": {
      "type": "remote",
      "url": "https://fourzerotwo.si/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add si-fourzerotwo-data --url 'https://fourzerotwo.si/mcp' --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  si-fourzerotwo-data:
    url: "https://fourzerotwo.si/mcp"
```

### Netclaw

```json
{
  "McpServers": {
    "si-fourzerotwo-data": {
      "Transport": "http",
      "Url": "https://fourzerotwo.si/mcp"
    }
  }
}
```

### Vellum

```bash
assistant mcp add si-fourzerotwo-data -t streamable-http -u 'https://fourzerotwo.si/mcp'
```

### Other

```json
{
  "mcpServers": {
    "si-fourzerotwo-data": {
      "type": "http",
      "url": "https://fourzerotwo.si/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 86, +1)

No change was recorded against any check on this day. Stability & Change Management went from 77 to 80. That category is still filling its 30-day observation window: 23 days of observed history at the previous scan, 24 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-11-03 (score 85, +1)

No change was recorded against any check on this day. Stability & Change Management went from 70 to 73. That category is still filling its 30-day observation window: 21 days of observed history at the previous scan, 22 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-11-01 (score 84, +1)

No change was recorded against any check on this day. Stability & Change Management went from 63 to 67. That category is still filling its 30-day observation window: 19 days of observed history at the previous scan, 20 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-30 (score 83, +1)

No change was recorded against any check on this day. Stability & Change Management went from 57 to 60. That category is still filling its 30-day observation window: 17 days of observed history at the previous scan, 18 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-28 (score 82, +1)

No change was recorded against any check on this day. Stability & Change Management went from 50 to 53. That category is still filling its 30-day observation window: 15 days of observed history at the previous scan, 16 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-26 (score 81, +1)

No change was recorded against any check on this day. Stability & Change Management went from 43 to 47. That category is still filling its 30-day observation window: 13 days of observed history at the previous scan, 14 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-23 (score 80, +1)

No change was recorded against any check on this day. Stability & Change Management went from 33 to 37. That category is still filling its 30-day observation window: 10 days of observed history at the previous scan, 11 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-21 (score 79, +1)

No change was recorded against any check on this day. Stability & Change Management went from 27 to 30. That category is still filling its 30-day observation window: 8 days of observed history at the previous scan, 9 at this one. The score rises as the window fills, whether or not the server changes.

## MCP tools (3)

### `search_apis` (~200 tokens)

Search data APIs

Find the right data endpoint for a task. Searches 500+ endpoints (UK legislation, Companies House, property prices, sanctions lists, vehicle tax, weather, earthquakes, arXiv/PubMed/Crossref papers, IP geolocation, GB electricity, ONS/World Bank/ECB economics, and more) by keyword and returns each match's tool name, parameters, price and free_tier. Always free to call. Next step: pass a returned tool name to call_api.

Input parameters:

- `category` (string): Optional category filter, e.g. "legal", "property", "finance", "research", "energy", "network". See list_apis for all categories.
- `limit` (integer): Maximum results (default 20).
- `query` (string): Keywords describing the data you need; every word must match. Examples: "postcode", "sanctions screen", "sold prices", "earthquake", "bank holiday".

Output parameters:

- `results` (array)
- `total` (integer)

### `list_apis` (~71 tokens)

List API groups

Overview of every API group in the catalog: name, category, summary, number of endpoints and whether it has a free tier. Always free to call. Use it to browse; use search_apis to find a specific endpoint.

Input parameters:

- `category` (string): Optional category filter, e.g. "property".

Output parameters:

- `apis` (array)
- `categories` (array)

### `call_api` (~178 tokens)

Call a data API

Run one endpoint by the tool name that search_apis returned, with that endpoint's parameters, and get its data back as JSON (with source and licence attribution). Endpoints with free_tier "free" or "sample" cost nothing within the daily allowance (100 calls/day anonymously, 500 with a free key). Otherwise the result is a payment request: pay in USDC via x402 and retry with _meta["x402/payment"]. Invalid arguments are rejected before any charge, and failed upstream calls are never charged.

Input parameters:

- `arguments` (object): The endpoint's parameters as listed in search_apis results, e.g. {"postcode": "SW1A 1AA"}.
- `tool` (string, required): Endpoint tool name from search_apis, e.g. "uk-postcodes__lookup" or "sanctions__screen".

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/si-fourzerotwo-data/fourzerotwo#diagnostics

## Score history

- 2026-11-05: 86
- 2026-11-04: 85
- 2026-11-03: 85
- 2026-11-02: 84
- 2026-11-01: 84
- 2026-10-31: 83
- 2026-10-30: 83
- 2026-10-29: 82
- 2026-10-28: 82
- 2026-10-27: 81
- 2026-10-26: 81
- 2026-10-25: 80
- 2026-10-24: 80
- 2026-10-23: 80
- 2026-10-22: 79
- 2026-10-21: 79
- 2026-10-20: 78
- 2026-10-19: 78
- 2026-10-18: 77
- 2026-10-17: 77
- 2026-10-16: 76
- 2026-10-15: 76
- 2026-10-14: 75
- 2026-10-13: 75
- 2026-10-12: 74

## Common questions

### What is the fourzerotwo MCP server?

fourzerotwo is an MCP server listed in the public MCP registry as si.fourzerotwo/data. 400+ data APIs for agents: UK companies, property, trade, tenders, recalls, sanctions. Free tier. This page covers its hosted endpoint (https://fourzerotwo.si/mcp).

### Is the fourzerotwo MCP server safe to use?

fourzerotwo scores 86 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 fourzerotwo MCP server expose?

fourzerotwo exposes 3 tools: search_apis, list_apis, call_api. Their descriptions and schemas cost roughly 449 tokens of context every time the server is loaded.

### Does the fourzerotwo MCP server require authentication?

No. We connected to fourzerotwo without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.

### Is the fourzerotwo MCP server still maintained?

fourzerotwo 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.

## Links

- Remote endpoint: https://fourzerotwo.si/mcp
- Website: https://fourzerotwo.si/
- Changelog RSS feed: https://verifymcp.io/servers/si-fourzerotwo-data/fourzerotwo.xml
- Changelog JSON feed: https://verifymcp.io/servers/si-fourzerotwo-data/fourzerotwo.json
- HTML version of this page: https://verifymcp.io/servers/si-fourzerotwo-data/fourzerotwo