Contraptify
REMOTE · MCP.CONTRAPTIFY.COM
Design redstone machines with your AI and test them tick by tick with Java Edition 26.3 rules.
Available components
Last scanned (23 hours ago)
Scores higher than 52% of remote servers
Reachable. Last reached 4 Nov 2026.
Category Entertainment and Games
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. How we score → Why this is hard to score →
Endpoint Security80
- The endpoint's TLS certificate is valid, in date, and uses a strong key. View diagnostics → Pass
- No authorisation is required to call this server. Every tool declares its destructiveHint and none is destructive, so open access doesn't expose one. See how to fix → View diagnostics → Partial
- HTTPS is enforced; there's no plaintext access path. View diagnostics → Pass
- The HSTS (Strict-Transport-Security) header is present. View diagnostics → Pass
- DNSSEC check failed: this domain isn't protected by DNSSEC. See how to fix → View diagnostics → Fail
Transport & Reachability100
- Verified streamable-http transport via a live MCP handshake. View diagnostics → Pass
Schema Quality & AI Usability30
- 0% of prompts and resources have a non-trivial description (not blank, and not just the item's name).Fail
- AI-judged instruction clarity (good).Pass
- Context-footprint check failed: tool/resource definitions use about 4643 tokens (~773/item across 6 items; 5 tools + 1 resources), over budget; trim descriptions and params. See how to fix → Fail
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management10
- Stability observed for 3 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
Tool Coverage93
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 80% of tool parameters carry a description.Partial
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 5 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 7 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
- Supports UI / widget rendering.Pass
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.
- 3 Nov 26 +1
- Resource “contraptify-viewer” now points somewhere else: ui://contraptify/viewer-152d365a3c27.html → ui://contraptify/viewer-9118fb9ac21e.html security
- The server rewrote its instructions, which are the text every model session reads security
- Tool “show” rewrote its description, which is the text the model reads security
- 2 Nov 26 0
- Stability: unverified → 0.03 ▲ functional
- 1 Nov 26 65
First indexed and scored.
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 4 Nov 2026 · Probed https://mcp.contraptify.com/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=*.contraptify.com | CN=YR1,O=Let's Encrypt,C=US | 21 Oct 2026 | 19 Jan 2027 | RSA 2048 | SHA256-RSA | 6e8af60e09a146080050dda19d4c478518b |
| SANs: *.contraptify.com, contraptify.com | ||||||
| CN=YR1,O=Let's Encrypt,C=US (CA) | CN=Root YR,O=ISRG,C=US | 3 Sept 2025 | 2 Sept 2028 | RSA 2048 | SHA256-RSA | a20253f15f2691c05dc1ce13b9bcca4e |
| CN=Root YR,O=ISRG,C=US (CA) | CN=ISRG Root X1,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | RSA 4096 | SHA256-RSA | f24b6d17f9d9ad7cb1c9fea78782699f |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of mcp.contraptify.com. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| com. | present | 19718 | 13 | Verified |
| contraptify.com. | absent | Unsigned (proven) parent-signed NSEC/NSEC3 proves an unsigned delegation |
Authentication No authorisation required
The endpoint answered without asking for a token. Anyone who knows the URL can reach it.
| Result | No authorisation required |
|---|---|
| HTTP status | 200 |
| Header | Value |
|---|---|
| strict-transport-security | max-age=63072000 |
| content-security-policy | frame-ancestors 'self' |
| x-frame-options | SAMEORIGIN |
| referrer-policy | strict-origin-when-cross-origin |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://mcp.contraptify.com/mcp | Verified | 200 | |
| http (plaintext) | http://mcp.contraptify.com/mcp | HTTPS enforced | 308 | https://mcp.contraptify.com/mcp |
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 →
explain Check a design's part explanations ~84
List a design's parts with their explanations, how many blocks each covers, and any blocks without a part. Use it before show to make sure every block is explained. Do not use it to test whether the machine works: use simulate.
| Name | Type | Req | Description |
|---|---|---|---|
| design | object | yes | A machine: a list of blocks plus what it is for. See the server instructions for block types and rules. |
No output schema declared.
No examples provided.
get_example Get an example design ~88
Return one built-in example design with its blocks, part explanations and its own test, by id from list_examples. Large designs (the 0-9 counter has about 2,500 blocks, the 00-59 clock about 5,100) are long. Do not use it to show an example to the user: use show with example set.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | – |
No output schema declared.
No examples provided.
list_examples List example designs ~56
List the built-in example designs (clocks, counters, a piston door, a lock, a flying machine). Use it to find a known-good starting point. Do not use it to fetch a design's blocks: use get_example.
Input schema present but exposes no named parameters.
No output schema declared.
No examples provided.
show Show a design in 3D ~152
Show a design to the user in an interactive 3D viewer in the chat: they can press its button or flip its lever, watch it run tick by tick, move around, and click any part to read what it does. Give either design, or example (an id from list_examples). Call it once per answer, at the end, after the last simulate passes: every call adds another viewer to the chat. Do not use it to test a design: use simulate.
| Name | Type | Req | Description |
|---|---|---|---|
| design | object | – | A machine: a list of blocks plus what it is for. See the server instructions for block types and rules. |
| example | string | – | Id of a built-in example to show instead of a design |
No output schema declared.
No examples provided.
simulate Simulate and test a design ~133
Run a redstone design with its own test (inputs and expectations) and return which expectations hold and which fail (with what the block was instead, and when), what visibly changed (lamps, pistons, doors, dispensers) and when, dispenser shots, and notes on what broke. Without a test it just runs the machine and reports what changed. Use it on every candidate before showing it. Do not use it to display a design to the user: use show.
| Name | Type | Req | Description |
|---|---|---|---|
| design | object | yes | A machine: a list of blocks plus what it is for. See the server instructions for block types and rules. |
No output schema declared.
No examples provided.
How do I install the Contraptify MCP server?
Contraptify is a hosted endpoint at https://mcp.contraptify.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.
remote · mcp.contraptify.com
claude mcp add --transport http torsviklabs-contraptify 'https://mcp.contraptify.com/mcp'
What is the Contraptify MCP server?
Contraptify is an MCP server listed in the public MCP registry as io.github.torsviklabs/contraptify. Design redstone machines with your AI and test them tick by tick with Java Edition 26.3 rules. This page covers its hosted endpoint (https://mcp.contraptify.com/mcp).
Is the Contraptify MCP server safe to use?
Contraptify scores 66 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 Contraptify MCP server expose?
Contraptify exposes 5 tools: simulate, explain, list_examples, get_example, show. Their descriptions and schemas cost roughly 513 tokens of context every time the server is loaded.
Does the Contraptify MCP server require authentication?
No. We connected to Contraptify without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the Contraptify MCP server still maintained?
Contraptify 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.