Nonobench
REMOTE · WWW.NONOBENCH.COM
An open-source benchmark of how well LLMs solve nonogram puzzles, from 5x5 to 20x20.
Available components
Last scanned (4 hours ago)
Scores higher than 93% of remote servers
Reachable. Last reached 5 Nov 2026.
Category Testing and QA
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 Security74
- 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
- HSTS check failed: the Strict-Transport-Security header is absent. See how to fix → View diagnostics → Fail
- 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 Usability78
- AI-judged instruction clarity (excellent).Pass
- Tool/resource definitions use about 956 tokens (~86/item across 11 items; 11 tools + 0 resources), lean.Pass
- Usage-examples check failed: none of the tools include examples. See how to fix → Fail
Stability & Change Management100
- No destabilizing schema changes in the last 30 days.Pass
Tool Coverage100
- 100% of tools have a non-trivial description (not blank, and not just the tool's name).Pass
- 100% of tool parameters carry a description.Pass
- Structured output schemas are declared (100% of tools); any adoption earns full credit.Pass
Tool Safety100
- No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
- We read all 11 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
- An AI judge read all 12 captured unit(s) of tool text and found none that tries to manipulate the model reading it.Pass
Capabilities100
- Implements a current MCP spec version (2026-07-28).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.
- 4 Nov 26 0
- The server rewrote its instructions, which are the text every model session reads security
- 29 Oct 26 +1
- Stability: 0.97 → pass security
- 27 Oct 26 +1
- The server rewrote its instructions, which are the text every model session reads security
- 25 Oct 26 +1
No change was recorded against any check on this day. Stability & Change Management went from 83 to 87. That category is still filling its 30-day observation window: 25 days of observed history at the previous scan, 26 at this one. The score rises as the window fills, whether or not the server changes.
- 24 Oct 26 0
- The server rewrote its instructions, which are the text every model session reads security
- 23 Oct 26 +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.
- 21 Oct 26 +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.
- 19 Oct 26 +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.
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 5 Nov 2026 · Probed https://www.nonobench.com/mcp
TLS valid
Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .
| Subject | Issuer | Valid from | Valid until | Key | Signature | Serial |
|---|---|---|---|---|---|---|
| CN=nonobench.com | CN=YE2,O=Let's Encrypt,C=US | 4 Nov 2026 | 2 Feb 2027 | ECDSA 256 | ECDSA-SHA384 | 6fde9c6747d40febe4e230e744dd389a27b |
| SANs: *.nonobench.com, nonobench.com | ||||||
| CN=YE2,O=Let's Encrypt,C=US (CA) | CN=Root YE,O=ISRG,C=US | 3 Sept 2025 | 2 Sept 2028 | ECDSA 384 | ECDSA-SHA384 | 4df3b15dd6c0784c507cd37b58e6f115 |
| CN=Root YE,O=ISRG,C=US (CA) | CN=ISRG Root X2,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | ECDSA 384 | ECDSA-SHA384 | 872165fc34b6e5fba8add5b3705fb53a |
| CN=ISRG Root X2,O=Internet Security Research Group,C=US (CA) | CN=ISRG Root X1,O=Internet Security Research Group,C=US | 13 May 2026 | 2 Sept 2032 | ECDSA 384 | SHA256-RSA | 6c8f1dc727c7117f7baf853ac980f9cd |
Background: What to check on a remote MCP endpoint →
DNSSEC insecure
Validation of www.nonobench.com. — Not signed
| Zone | DS | Keys | Algorithms | Outcome |
|---|---|---|---|---|
| . | trust_anchor | 20326, 38696 | 8, 8 | Verified |
| com. | present | 19718 | 13 | Verified |
| nonobench.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 |
Background: How OAuth 2.1 works in the 2026 MCP spec →
Transports 2 probes
| Transport | URL | Outcome | Status | Location |
|---|---|---|---|---|
| streamable-http | https://www.nonobench.com/mcp | Verified | 200 | |
| http (plaintext) | http://www.nonobench.com/mcp | HTTPS enforced | 301 | https://www.nonobench.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 →
check_solution Check solution ~74
Check a grid against a puzzle's clues, using the same rule as the benchmark grader. Reports which rows and columns do not match.
| Name | Type | Req | Description |
|---|---|---|---|
| grid | string | yes | Row-major string of 0 (empty) and 1 (filled), width × height characters |
| id | string | yes | Puzzle id from list_puzzles |
| Name | Type | Req | Description |
|---|---|---|---|
| columnViolations | array | yes | – |
| correct | boolean | yes | – |
| error | string | – | – |
| rowViolations | array | yes | – |
No examples provided.
compare_models Compare models ~69
Side-by-side core overall and per-size accuracy, cost, latency and token results for model or family names.
| Name | Type | Req | Description |
|---|---|---|---|
| models | array | yes | 2 to 20 model variant ids or family names, e.g. claude-opus-5.5 or gpt-6-astra-xhigh |
| Name | Type | Req | Description |
|---|---|---|---|
| models | array | yes | – |
No examples provided.
get_leaderboard Get leaderboard ~185
Models ranked by accuracy; defaults to all effort levels for compatibility.
| Name | Type | Req | Description |
|---|---|---|---|
| effort | string | – | best, all (default), or one effort level; empty means all |
| family | string | – | Comma-separated family ids; empty means no filter |
| min_correct | integer | – | Minimum puzzles solved in the selected tier; default 0 includes unsolved variants |
| open_weights | boolean | – | Only open-weight (true) or closed (false) models |
| provider | string | – | Comma-separated provider ids; empty means no filter |
| reasoning | boolean | – | Only reasoning (true) or non-reasoning (false) variants |
| size | string | – | Grid size to filter on |
| version | string | – | Comma-separated benchmark versions: 1.0, 1.1, 1.2; empty means all |
| Name | Type | Req | Description |
|---|---|---|---|
| models | array | yes | – |
| size | string | yes | – |
| updatedAt | string | yes | – |
No examples provided.
get_model_puzzles Get model puzzles ~55
Which puzzles one model solved, missed, timed out on, or has not run.
| Name | Type | Req | Description |
|---|---|---|---|
| model | string | yes | Model variant id as listed on the leaderboard, e.g. claude-opus-5.5-high |
| Name | Type | Req | Description |
|---|---|---|---|
| attempted | number | yes | – |
| displayName | string | yes | – |
| model | string | yes | – |
| puzzles | array | yes | – |
| solved | number | yes | – |
No examples provided.
get_model_results Get model results ~53
Accuracy, cost, latency and token use for one model, broken down by grid size.
| Name | Type | Req | Description |
|---|---|---|---|
| model | string | yes | Model name as listed on the leaderboard, e.g. gpt-5.4-xhigh |
| Name | Type | Req | Description |
|---|---|---|---|
| accuracy | number | yes | Percentage of puzzles solved |
| bySize | array | yes | – |
| correct | number | yes | – |
| displayName | string | yes | – |
| effort | string|null | yes | – |
| failedRuns | number | yes | – |
| family | string | yes | – |
| model | string | yes | Model variant id, e.g. claude-opus-5.5-high |
| provider | string|null | yes | – |
| reasoning | boolean | yes | – |
| total | number | yes | – |
No examples provided.
get_puzzle Get puzzle ~62
One puzzle, including the clue text models were prompted with. The reference solution is only included on request; some puzzles have several valid solutions.
| Name | Type | Req | Description |
|---|---|---|---|
| id | string | yes | Puzzle id from list_puzzles |
| include_solution | boolean | – | Include a reference solution |
| Name | Type | Req | Description |
|---|---|---|---|
| columnClues | array | yes | – |
| height | number | yes | – |
| id | string | yes | – |
| index | number | yes | – |
| prompt | string | yes | Clue text as models received it |
| referenceSolution | string | – | – |
| rowClues | array | yes | – |
| size | string | yes | – |
| url | string | yes | – |
| width | number | yes | – |
No examples provided.
get_puzzle_results Get puzzle results ~142
Per-model outcomes for one puzzle. Answers are omitted unless requested.
| Name | Type | Req | Description |
|---|---|---|---|
| effort | string | – | best, all (default), or one effort level |
| family | string | – | Comma-separated family ids; empty means no filter |
| id | string | yes | Puzzle id from list_puzzles |
| include_answers | boolean | – | Include each model's answer grid |
| open_weights | boolean | – | Only open-weight (true) or closed (false) models |
| provider | string | – | Comma-separated provider ids; empty means no filter |
| reasoning | boolean | – | Only reasoning (true) or non-reasoning (false) variants |
| Name | Type | Req | Description |
|---|---|---|---|
| attempts | number | yes | – |
| index | number | yes | – |
| puzzleId | string | yes | – |
| runs | array | yes | – |
| size | string | yes | – |
| solved | number | yes | – |
| updatedAt | string | yes | – |
No examples provided.
list_families List families ~19
Model families, available efforts and best variants.
Input schema present but exposes no named parameters.
| Name | Type | Req | Description |
|---|---|---|---|
| families | array | yes | – |
No examples provided.
list_providers List providers ~19
Provider ids, names, families and variant counts.
Input schema present but exposes no named parameters.
| Name | Type | Req | Description |
|---|---|---|---|
| providers | array | yes | – |
No examples provided.
list_puzzles List puzzles ~33
The benchmark puzzles with their ids and row/column clues.
| Name | Type | Req | Description |
|---|---|---|---|
| size | string | – | Grid size to filter on |
| Name | Type | Req | Description |
|---|---|---|---|
| puzzles | array | yes | – |
No examples provided.
list_runs List runs ~114
Individual benchmark runs (one model on one puzzle), optionally with the raw prompt and model output.
| Name | Type | Req | Description |
|---|---|---|---|
| include_output | boolean | – | Include raw prompt and model output (large) |
| limit | integer | – | Default 100 |
| model | string | – | Only runs of this model variant id |
| offset | integer | – | Runs to skip, for paging; default 0 |
| puzzle_id | string | – | Only runs on this puzzle id from list_puzzles |
| size | string | – | Grid size to filter on |
| Name | Type | Req | Description |
|---|---|---|---|
| limit | number | yes | – |
| offset | number | yes | – |
| runs | array | yes | – |
| total | number | yes | – |
No examples provided.
How do I install the Nonobench MCP server?
Nonobench is a hosted endpoint at https://www.nonobench.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 · www.nonobench.com
claude mcp add --transport http mauricekleine-nonobench 'https://www.nonobench.com/mcp'
What is the Nonobench MCP server?
Nonobench is an MCP server listed in the public MCP registry as io.github.mauricekleine/nonobench. An open-source benchmark of how well LLMs solve nonogram puzzles, from 5x5 to 20x20. This page covers its hosted endpoint (https://www.nonobench.com/mcp).
Is the Nonobench MCP server safe to use?
Nonobench 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 Nonobench MCP server expose?
Nonobench exposes 11 tools: get_leaderboard, list_providers, list_families, compare_models, get_model_results, and 6 more. Their descriptions and schemas cost roughly 825 tokens of context every time the server is loaded.
Does the Nonobench MCP server require authentication?
No. We connected to Nonobench without credentials and it answered, so anything it exposes is reachable by anyone who knows the address.
Is the Nonobench MCP server still maintained?
Nonobench 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.