# PT Chart (remote · pt-chart-mcp-production.up.railway.app)

PT chart lookups, superheat/subcooling calculators, and diagnostics for HVAC technicians.

- Trust score: 63/100 (medium)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-10-22

## Components

- remote · `pt-chart-mcp-production.up.railway.app`: 63/100 (this document), [markdown](https://verifymcp.io/servers/tsonnn-pt-chart-mcp/pt-chart-mcp-production.md), [page](https://verifymcp.io/servers/tsonnn-pt-chart-mcp/pt-chart-mcp-production)

## Channel facts

- Endpoint: `https://pt-chart-mcp-production.up.railway.app/mcp`
- 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 2026-10-22.

- **Endpoint Security**: 57/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - Authorisation not fully verified: no authorisation is required to call this server, and 8 tool(s) never declared a destructiveHint. The MCP spec treats an absent hint as destructive by default, so we cannot call this surface safe.
  - HTTPS is enforced; there's no plaintext access path.
  - HSTS check failed: the Strict-Transport-Security header is absent.
  - 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**: 70/100
  - AI-judged instruction clarity (good).
  - Tool/resource definitions use about 835 tokens (~104/item across 8 items; 8 tools + 0 resources), lean.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 13/100
  - Stability observed for 4 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 67/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 0% 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 8 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 8 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 PT Chart MCP server?

PT Chart is a hosted endpoint at https://pt-chart-mcp-production.up.railway.app/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 tsonnn-pt-chart-mcp 'https://pt-chart-mcp-production.up.railway.app/mcp'
```

### Cursor

```json
{
  "mcpServers": {
    "tsonnn-pt-chart-mcp": {
      "url": "https://pt-chart-mcp-production.up.railway.app/mcp"
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "tsonnn-pt-chart-mcp": {
      "type": "http",
      "url": "https://pt-chart-mcp-production.up.railway.app/mcp"
    }
  }
}
```

### Codex

```toml
[mcp_servers.tsonnn-pt-chart-mcp]
url = "https://pt-chart-mcp-production.up.railway.app/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "tsonnn-pt-chart-mcp": {
      "type": "remote",
      "url": "https://pt-chart-mcp-production.up.railway.app/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add tsonnn-pt-chart-mcp --url 'https://pt-chart-mcp-production.up.railway.app/mcp' --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  tsonnn-pt-chart-mcp:
    url: "https://pt-chart-mcp-production.up.railway.app/mcp"
```

### Netclaw

```json
{
  "McpServers": {
    "tsonnn-pt-chart-mcp": {
      "Transport": "http",
      "Url": "https://pt-chart-mcp-production.up.railway.app/mcp"
    }
  }
}
```

### Vellum

```bash
assistant mcp add tsonnn-pt-chart-mcp -t streamable-http -u 'https://pt-chart-mcp-production.up.railway.app/mcp'
```

### Other

```json
{
  "mcpServers": {
    "tsonnn-pt-chart-mcp": {
      "type": "http",
      "url": "https://pt-chart-mcp-production.up.railway.app/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.

### 2026-10-22 (score 63, +1)

No change was recorded against any check on this day. Stability & Change Management went from 10 to 13. That category is still filling its 30-day observation window: 3 days of observed history at the previous scan, 4 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-20 (score 62, +1)

No change was recorded against any check on this day. Stability & Change Management went from 3 to 7. That category is still filling its 30-day observation window: 1 days of observed history at the previous scan, 2 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-10-19 (score 61, 0)

- [functional improvement] Stability: unverified → 0.03

### 2026-10-18 (score 61)

First indexed and scored.

## MCP tools (8)

### `pt_lookup` (~129 tokens)

Saturation pressure (bubble and dew, in psig) for a refrigerant at a
temperature in Fahrenheit. For certified HVAC technicians (EPA 608; A2L
certification where required). Example: pt_lookup("R-454B", 45).

Bubble point: use for subcooling calculations. Dew point: use for
superheat calculations. Pure fluids (R-32, R-410A, R-22, R-134a) have
no glide, so both values match.

Input parameters:

- `refrigerant` (string, required)
- `temp_f` (number, required)

### `pt_reverse` (~120 tokens)

Saturation temperature (bubble and dew, in Fahrenheit) for a
refrigerant at a pressure in psig. For certified HVAC technicians
(EPA 608; A2L certification where required). Example: a 130 psig
suction reading on R-454B -- pt_reverse("R-454B", 130).

Use the DEW temperature for superheat work and the BUBBLE temperature
for subcooling work on blended refrigerants.

Input parameters:

- `pressure_psig` (number, required)
- `refrigerant` (string, required)

### `superheat` (~103 tokens)

Superheat in Fahrenheit from suction pressure (psig) and suction-line
temperature (F). For certified HVAC technicians (EPA 608; A2L
certification where required). Uses the DEW point as the saturation
basis, which is the correct basis for blended refrigerants.
Typical TXV target: 8-12F.

Input parameters:

- `refrigerant` (string, required)
- `suction_line_f` (number, required)
- `suction_psig` (number, required)

### `subcooling` (~106 tokens)

Subcooling in Fahrenheit from head pressure (psig) and liquid-line
temperature (F). For certified HVAC technicians (EPA 608; A2L
certification where required). Uses the BUBBLE point as the saturation
basis, which is the correct basis for blended refrigerants.
Typical TXV target: 8-12F.

Input parameters:

- `head_psig` (number, required)
- `liquid_line_f` (number, required)
- `refrigerant` (string, required)

### `convert_units` (~85 tokens)

Convert between pressure units (psig, psia, kpa, bar) and temperature
units (F, C). A bare 'psi' is treated as psig. For certified HVAC
technicians (EPA 608; A2L certification where required).

Input parameters:

- `from_unit` (string, required)
- `to_unit` (string, required)
- `value` (number, required)

### `refrigerant_info` (~67 tokens)

Reference card for a refrigerant: GWP, ASHRAE safety class,
composition, typical oil, temperature glide, and handling notes.
For certified HVAC technicians (EPA 608; A2L certification where
required). Informational only.

Input parameters:

- `refrigerant` (string, required)

### `diagnose` (~164 tokens)

Conversational diagnostic copilot: give it field readings and get back
computed superheat/subcooling plus a ranked 'check this first' list.
For certified HVAC technicians (EPA 608; A2L certification where
required). Informational only -- it suggests what to CHECK, never how
to defeat a safety device, vent refrigerant, or work uncertified.

metering: 'txv' (default) or 'fixed' for fixed-orifice/piston systems.

Input parameters:

- `ambient_f` (number, required)
- `head_psig` (number, required)
- `liquid_line_f` (number, required)
- `metering` (string)
- `refrigerant` (string, required)
- `suction_line_f` (number, required)
- `suction_psig` (number, required)

### `coolbooked_info` (~61 tokens)

About CoolBooked: the AI appointment-booking connector for HVAC shops.
This is NOT a diagnostic tool -- call it when someone asks what
CoolBooked is, how shop owners can try it, or how the free PT tools
connect to paid bookings.

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/tsonnn-pt-chart-mcp/pt-chart-mcp-production#diagnostics

## Score history

- 2026-10-22: 63
- 2026-10-21: 62
- 2026-10-20: 62
- 2026-10-19: 61
- 2026-10-18: 61

## Common questions

### What is the PT Chart MCP server?

PT Chart is an MCP server listed in the public MCP registry as io.github.Tsonnn/pt-chart-mcp. PT chart lookups, superheat/subcooling calculators, and diagnostics for HVAC technicians. This page covers its hosted endpoint (https://pt-chart-mcp-production.up.railway.app/mcp).

### Is the PT Chart MCP server safe to use?

PT Chart scores 63 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 PT Chart MCP server expose?

PT Chart exposes 8 tools: pt_lookup, pt_reverse, superheat, subcooling, convert_units, and 3 more. Their descriptions and schemas cost roughly 835 tokens of context every time the server is loaded.

### Does the PT Chart MCP server require authentication?

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

### Is the PT Chart MCP server still maintained?

PT Chart is still listed as active in the MCP registry. We last reached this channel on 22 October 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://pt-chart-mcp-production.up.railway.app/mcp
- Website: https://coolbooked.com/tools/pt-chart/
- Changelog RSS feed: https://verifymcp.io/servers/tsonnn-pt-chart-mcp/pt-chart-mcp-production.xml
- Changelog JSON feed: https://verifymcp.io/servers/tsonnn-pt-chart-mcp/pt-chart-mcp-production.json
- HTML version of this page: https://verifymcp.io/servers/tsonnn-pt-chart-mcp/pt-chart-mcp-production