# FaxOnline (remote · faxonline.app)

Prepare and track US PDF faxes with user-approved checkout. No account or subscription.

- Trust score: 83/100 (high trust)
- Change this week: +3
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-11-04

## Components

- remote · `faxonline.app`: 83/100 (this document), [markdown](https://verifymcp.io/servers/abrudtkuhl-faxonline/mcp-fax.md), [page](https://verifymcp.io/servers/abrudtkuhl-faxonline/mcp-fax)

## Channel facts

- Endpoint: `https://faxonline.app/mcp/fax`
- Transports: `streamable-http`
- Auth: `none`
- Version: `1.0.0`

## 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 2026-11-04.

- **Endpoint Security**: 77/100
  - 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.
  - HSTS check failed: the Strict-Transport-Security header is absent.
  - DNSSEC is configured correctly; the domain's records validate against the full chain to the root.
- **Transport & Reachability**: 100/100
  - Verified streamable-http transport via a live MCP handshake.
- **Schema Quality & AI Usability**: 69/100
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 422 tokens (~211/item across 2 items; 2 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 83/100
  - Stability observed for 25 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 2 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 3 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 FaxOnline MCP server?

FaxOnline is a hosted endpoint at https://faxonline.app/mcp/fax, 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 abrudtkuhl-faxonline 'https://faxonline.app/mcp/fax'
```

### Cursor

```json
{
  "mcpServers": {
    "abrudtkuhl-faxonline": {
      "url": "https://faxonline.app/mcp/fax"
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "abrudtkuhl-faxonline": {
      "type": "http",
      "url": "https://faxonline.app/mcp/fax"
    }
  }
}
```

### Codex

```toml
[mcp_servers.abrudtkuhl-faxonline]
url = "https://faxonline.app/mcp/fax"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "abrudtkuhl-faxonline": {
      "type": "remote",
      "url": "https://faxonline.app/mcp/fax",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add abrudtkuhl-faxonline --url 'https://faxonline.app/mcp/fax' --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  abrudtkuhl-faxonline:
    url: "https://faxonline.app/mcp/fax"
```

### Netclaw

```json
{
  "McpServers": {
    "abrudtkuhl-faxonline": {
      "Transport": "http",
      "Url": "https://faxonline.app/mcp/fax"
    }
  }
}
```

### Vellum

```bash
assistant mcp add abrudtkuhl-faxonline -t streamable-http -u 'https://faxonline.app/mcp/fax'
```

### Other

```json
{
  "mcpServers": {
    "abrudtkuhl-faxonline": {
      "type": "http",
      "url": "https://faxonline.app/mcp/fax"
    }
  }
}
```

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.

### 2026-11-04 (score 83, +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.

### 2026-11-02 (score 82, +1)

No change was recorded against any check on this day. Stability & Change Management went from 73 to 77. That category is still filling its 30-day observation window: 22 days of observed history at the previous scan, 23 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-30 (score 81, +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.

### 2026-10-28 (score 80, +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.

### 2026-10-26 (score 79, +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.

### 2026-10-24 (score 78, +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.

### 2026-10-22 (score 77, +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.

### 2026-10-20 (score 76, +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.

## MCP tools (2)

### `prepare_fax` (~243 tokens)

Prepare Fax

Prepare one PDF fax and return its price and Stripe checkout link. This stores the document but does not send or charge. Completing checkout authorizes sending to the displayed recipient. fax_number must be a US fax number: 10 digits (5155551234), optionally prefixed with 1 or +1 (E.164 such as +15155551234); common formatting such as (515) 555-1234 is accepted. Keep draft_token private and reuse it with identical inputs for retries.

Input parameters:

- `document_base64` (string, required): Standard base64 of the PDF bytes, without a data URL prefix; maximum decoded size 10 MiB.
- `draft_token` (string, required): A secret, cryptographically random 64-character lowercase hex token. Reuse for retries and status checks.
- `email` (string, required): Email address for delivery notifications.
- `fax_number` (string, required): US destination fax number: 10 digits (5155551234), optionally prefixed with 1 or +1 (+15155551234). Common formatting such as (515) 555-1234 is accepted.
- `filename` (string, required): PDF filename without directory paths.

### `get_fax_status` (~61 tokens)

Get Fax Status

Check your prepared fax using its secret draft_token. Returns payment and delivery status. A processing fax has not yet been delivered. Poll no more than once every 15 seconds.

Input parameters:

- `draft_token` (string, required): The private token used in prepare_fax.

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/abrudtkuhl-faxonline/mcp-fax#diagnostics

## Score history

- 2026-11-04: 83
- 2026-11-03: 82
- 2026-11-02: 82
- 2026-11-01: 81
- 2026-10-31: 81
- 2026-10-30: 81
- 2026-10-29: 80
- 2026-10-28: 80
- 2026-10-27: 79
- 2026-10-26: 79
- 2026-10-25: 78
- 2026-10-24: 78
- 2026-10-23: 77
- 2026-10-22: 77
- 2026-10-21: 76
- 2026-10-20: 76
- 2026-10-19: 75
- 2026-10-18: 75
- 2026-10-17: 74
- 2026-10-16: 74
- 2026-10-15: 74
- 2026-10-14: 74
- 2026-10-13: 73
- 2026-10-12: 73
- 2026-10-10: 72

## Common questions

### What is the FaxOnline MCP server?

FaxOnline is an MCP server listed in the public MCP registry as io.github.abrudtkuhl/faxonline. Prepare and track US PDF faxes with user-approved checkout. No account or subscription. This page covers its hosted endpoint (https://faxonline.app/mcp/fax).

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

FaxOnline scores 83 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 FaxOnline MCP server expose?

FaxOnline exposes 2 tools: prepare_fax, get_fax_status. Their descriptions and schemas cost roughly 304 tokens of context every time the server is loaded.

### Does the FaxOnline MCP server require authentication?

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

### Is the FaxOnline MCP server still maintained?

FaxOnline is still listed as active in the MCP registry. We last reached this channel on 4 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://faxonline.app/mcp/fax
- Website: https://faxonline.app/fax-for-ai-agents
- Changelog RSS feed: https://verifymcp.io/servers/abrudtkuhl-faxonline/mcp-fax.xml
- Changelog JSON feed: https://verifymcp.io/servers/abrudtkuhl-faxonline/mcp-fax.json
- HTML version of this page: https://verifymcp.io/servers/abrudtkuhl-faxonline/mcp-fax