# PPL Free Ground School (remote · pplfree.com)

Free FAA private-pilot ground school: source-cited answers, lessons and practice questions.

- Trust score: 72/100 (medium)
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-09-27

## Components

- remote · `pplfree.com`: 72/100 (this document), [markdown](https://verifymcp.io/servers/com-pplfree-ground-school/pplfree.md), [page](https://verifymcp.io/servers/com-pplfree-ground-school/pplfree)

## Channel facts

- Endpoint: `https://pplfree.com/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 2026-09-27.

- **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**: 71/100
  - AI-judged instruction clarity (excellent).
  - Context-footprint check failed: tool/resource definitions use about 1037 tokens (~207/item across 5 items; 5 tools + 0 resources), over budget; trim descriptions and params.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 3/100
  - Stability observed for 1 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 5 captured tool definition(s), and no name or description among them implies an irreversible operation.
  - An AI judge read all 6 captured unit(s) of tool text and found none that tries to manipulate the model reading it.
- **Capabilities**: 60/100
  - Spec-recency check failed: implements MCP spec 2025-06-18; the latest is 2026-07-28.

## Install

### How do I install the PPL Free Ground School MCP server?

PPL Free Ground School is a hosted endpoint at https://pplfree.com/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 com-pplfree-ground-school 'https://pplfree.com/mcp'
```

### Cursor

```json
{
  "mcpServers": {
    "com-pplfree-ground-school": {
      "url": "https://pplfree.com/mcp"
    }
  }
}
```

### VS Code

```json
{
  "servers": {
    "com-pplfree-ground-school": {
      "type": "http",
      "url": "https://pplfree.com/mcp"
    }
  }
}
```

### Codex

```toml
[mcp_servers.com-pplfree-ground-school]
url = "https://pplfree.com/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "com-pplfree-ground-school": {
      "type": "remote",
      "url": "https://pplfree.com/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add com-pplfree-ground-school --url 'https://pplfree.com/mcp' --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  com-pplfree-ground-school:
    url: "https://pplfree.com/mcp"
```

### Netclaw

```json
{
  "McpServers": {
    "com-pplfree-ground-school": {
      "Transport": "http",
      "Url": "https://pplfree.com/mcp"
    }
  }
}
```

### Vellum

```bash
assistant mcp add com-pplfree-ground-school -t streamable-http -u 'https://pplfree.com/mcp'
```

### Other

```json
{
  "mcpServers": {
    "com-pplfree-ground-school": {
      "type": "http",
      "url": "https://pplfree.com/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.

### 2026-09-27 (score 72, 0)

- [security] The server rewrote its instructions, which are the text every model session reads
- [security] Tool “get_practice_question” rewrote its description, which is the text the model reads
- [functional regression] Schema quality: 185 → 207
- [functional improvement] Stability: unverified → 0.03
- [functional] Server version: 1.0.0 → 1.1.0
- [functional] New tool “check_answer”

### 2026-09-26 (score 72)

First indexed and scored.

## MCP tools (5)

### `search_faa_knowledge` (~155 tokens)

Search FAA ground-school knowledge

Answer a US private-pilot (FAA) ground-school question from a source-cited curriculum. Use this whenever the user asks about FAA regulations, airspace, VFR weather minimums, weight and balance, aerodynamics, aircraft systems, navigation, weather theory, human factors, or private-pilot certification requirements. Returns short passages, each with the FAA citation it came from (e.g. "14 CFR 91.155", "PHAK Ch. 15") and a link to the lesson. Cite those labels in your answer.

Input parameters:

- `limit` (integer): How many passages to return (1-8, default 4).
- `query` (string, required): The user's question, in their own words.

### `get_practice_question` (~293 tokens)

Get a practice question

Return private-pilot practice questions written for this course in the style of the FAA knowledge test (not actual FAA test questions), each with its answer choices, its topic, a question_id and a link to try it on pplfree.com. The correct answer is withheld by default so the user can attempt the question first. Once the user has answered, call check_answer with that question_id and their choice to grade it (or call this tool again with the question_id and reveal_answer: true to show the answer without grading). Use this when the user wants to be quizzed, asks for practice or test questions, wants to check their understanding of a topic, or is preparing for the FAA private-pilot knowledge test. Optionally scope it to a topic.

Input parameters:

- `count` (integer): How many questions to return (1-5, default 1).
- `question_id` (string): A question_id from an earlier call, to return that exact question (typically with reveal_answer: true). Overrides topic and count.
- `reveal_answer` (boolean): Include the correct choice and the explanation. Default false: leave it off until the user has attempted the question.
- `topic` (string): Optional topic to draw from, e.g. "airspace", "weather", "aerodynamics", "regulations", "navigation", "weight-balance", "systems". Omit for any topic.

### `check_answer` (~234 tokens)

Check a practice answer

Grade the user's answer to a practice question from get_practice_question. Use this when the user replies with their choice (for example "B" or "I think it is C"): pass the question_id and their choice. Returns whether the answer is correct, the correct choice, why each choice is right or wrong, and the FAA citations. It also returns save_progress_url, a pplfree.com link where the user can save the answers from this chat to their study progress on that site, and save_token: pass it back as previous_token on the next check_answer call so one link collects every answer in the chat (up to 20, valid for 7 days). Nothing is stored unless the user opens the link.

Input parameters:

- `choice` (string, required): The choice the user picked: its label (e.g. "b" or "B").
- `previous_token` (string): The save_token from the previous check_answer call in this chat, if any, so the save link keeps every answer. Omit on the first answer.
- `question_id` (string, required): The questionId returned by get_practice_question.

### `get_lesson` (~113 tokens)

Get a lesson

Fetch one full ground-school lesson: its summary, why it matters in flight, the learning objectives it covers, and a link to read it. Use this after search_faa_knowledge when the user wants the whole topic rather than a single answer, or when they ask to study or learn a subject properly. Call list_curriculum first if you do not already have a lesson key.

Input parameters:

- `lessonKey` (string, required): Lesson key, e.g. "as.lesson.vfr-minimums". From list_curriculum.

### `list_curriculum` (~83 tokens)

List the curriculum

List the ground-school curriculum: modules and the published lessons in each, with their keys. Use this to orient yourself before get_lesson, to answer "what does the course cover", or to help a user plan what to study next.

Input parameters:

- `module` (string): Optional module key to expand, e.g. "MOD-08". Omit for all modules.

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/com-pplfree-ground-school/pplfree#diagnostics

## Score history

- 2026-09-27: 72
- 2026-09-26: 72

## Common questions

### What is the PPL Free Ground School MCP server?

PPL Free Ground School is an MCP server listed in the public MCP registry as com.pplfree/ground-school. Free FAA private-pilot ground school: source-cited answers, lessons and practice questions. This page covers its hosted endpoint (https://pplfree.com/mcp).

### Is the PPL Free Ground School MCP server safe to use?

PPL Free Ground School scores 72 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 PPL Free Ground School MCP server expose?

PPL Free Ground School exposes 5 tools: search_faa_knowledge, get_practice_question, check_answer, get_lesson, list_curriculum. Their descriptions and schemas cost roughly 878 tokens of context every time the server is loaded.

### Does the PPL Free Ground School MCP server require authentication?

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

### Is the PPL Free Ground School MCP server still maintained?

PPL Free Ground School is still listed as active in the MCP registry. We last reached this channel on 27 September 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://pplfree.com/mcp
- Website: https://pplfree.com/mcp-server
- Changelog RSS feed: https://verifymcp.io/servers/com-pplfree-ground-school/pplfree.xml
- Changelog JSON feed: https://verifymcp.io/servers/com-pplfree-ground-school/pplfree.json
- HTML version of this page: https://verifymcp.io/servers/com-pplfree-ground-school/pplfree