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Sports Rules

REMOTE · SPORTS-RULES.GUMBALLTOOLS.COM · SCANNED SEP 25

Work an offside call through IFAB Law 11 or NHL Rule 83, step by step.

+3 this week 73 Trust /100
Trust breakdown (7 categories)

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 Security63
Transport & Reachability100
Schema Quality & AI Usability58
  • AI-judged instruction clarity (excellent).Pass
  • Context-footprint check failed: tool/resource definitions use about 1251 tokens (~625/item across 2 items; 2 tools + 0 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 Management67
  • Stability observed for 20 of 30 days with no destabilising changes; credit accrues until the full window elapses.Partial
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
Tool Safety100
  • No prompt-injection markers were found in the server instructions, tool names or descriptions we captured.Pass
  • We read all 2 captured tool definition(s), and no name or description among them implies an irreversible operation.Pass
  • An AI judge read all 2 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
Install

How do I install the Sports Rules MCP server?

Sports Rules is a hosted endpoint at https://sports-rules.gumballtools.com/api/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 · sports-rules.gumballtools.com

# add to Claude Code
claude mcp add --transport http com-gumballtools-sports-rules 'https://sports-rules.gumballtools.com/api/mcp'
// .cursor/mcp.json
{
  "mcpServers": {
    "com-gumballtools-sports-rules": {
      "url": "https://sports-rules.gumballtools.com/api/mcp"
    }
  }
}
// .vscode/mcp.json
{
  "servers": {
    "com-gumballtools-sports-rules": {
      "type": "http",
      "url": "https://sports-rules.gumballtools.com/api/mcp"
    }
  }
}
# ~/.codex/config.toml
[mcp_servers.com-gumballtools-sports-rules]
url = "https://sports-rules.gumballtools.com/api/mcp"
// opencode.json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "com-gumballtools-sports-rules": {
      "type": "remote",
      "url": "https://sports-rules.gumballtools.com/api/mcp",
      "enabled": true
    }
  }
}
# add to OpenClaw
openclaw mcp add com-gumballtools-sports-rules --url 'https://sports-rules.gumballtools.com/api/mcp' --transport streamable-http
# ~/.hermes/config.yaml
mcp_servers:
  com-gumballtools-sports-rules:
    url: "https://sports-rules.gumballtools.com/api/mcp"
// ~/.netclaw/config/netclaw.json
{
  "McpServers": {
    "com-gumballtools-sports-rules": {
      "Transport": "http",
      "Url": "https://sports-rules.gumballtools.com/api/mcp"
    }
  }
}
# add to Vellum
assistant mcp add com-gumballtools-sports-rules -t streamable-http -u 'https://sports-rules.gumballtools.com/api/mcp'
// mcp.json
{
  "mcpServers": {
    "com-gumballtools-sports-rules": {
      "type": "http",
      "url": "https://sports-rules.gumballtools.com/api/mcp"
    }
  }
}

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

Changelog

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.

  • 25 Sept 26 +1
    • We updated how we score, so this day's move reflects our rubric, not a change to the server See what changed → functional
  • 22 Sept 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 53 to 57. That category is still filling its 30-day observation window: 16 days of observed history at the previous scan, 17 at this one. The score rises as the window fills, whether or not the server changes.

  • 20 Sept 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 47 to 50. That category is still filling its 30-day observation window: 14 days of observed history at the previous scan, 15 at this one. The score rises as the window fills, whether or not the server changes.

  • 18 Sept 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 40 to 43. That category is still filling its 30-day observation window: 12 days of observed history at the previous scan, 13 at this one. The score rises as the window fills, whether or not the server changes.

  • 16 Sept 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 33 to 37. That category is still filling its 30-day observation window: 10 days of observed history at the previous scan, 11 at this one. The score rises as the window fills, whether or not the server changes.

  • 14 Sept 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 27 to 30. That category is still filling its 30-day observation window: 8 days of observed history at the previous scan, 9 at this one. The score rises as the window fills, whether or not the server changes.

  • 12 Sept 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 20 to 23. That category is still filling its 30-day observation window: 6 days of observed history at the previous scan, 7 at this one. The score rises as the window fills, whether or not the server changes.

  • 10 Sept 26 +1

    No change was recorded against any check on this day. Stability & Change Management went from 13 to 17. That category is still filling its 30-day observation window: 4 days of observed history at the previous scan, 5 at this one. The score rises as the window fills, whether or not the server changes.

Diagnostics

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 25 Sept 2026 · Probed https://sports-rules.gumballtools.com/api/mcp

TLS valid

Negotiated TLS 1.3 with TLS_AES_128_GCM_SHA256 .

Subject Issuer Valid from Valid until Key Signature Serial
CN=*.gumballtools.com CN=YR2,O=Let's Encrypt,C=US 6 Sept 2026 5 Dec 2026 RSA 2048 SHA256-RSA 60927985e79d22e7a1106139f609d74b0e4
SANs: *.gumballtools.com, gumballtools.com
CN=YR2,O=Let's Encrypt,C=US (CA) CN=Root YR,O=ISRG,C=US 3 Sept 2025 2 Sept 2028 RSA 2048 SHA256-RSA 4ebd24947e24d394802d84a52fd5b319
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 sports-rules.gumballtools.com. — Not signed

Zone DS Keys Algorithms Outcome
. trust_anchor 20326, 38696 8, 8 Verified
com. present 19718 13 Verified
gumballtools.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

Background: How OAuth 2.1 works in the 2026 MCP spec →

Transports 2 probes
Transport URL Outcome Status Location
streamable-http https://sports-rules.gumballtools.com/api/mcp Verified 200
http (plaintext) http://sports-rules.gumballtools.com/api/mcp HTTPS enforced 308 https://sports-rules.gumballtools.com/api/mcp
MCP tools · 2 exposed · ~1,251 tokens

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 →

Tool Tokens
offside ~1,134

Work an offside call through the published decision procedure — association football under IFAB Law 11, or ice hockey under NHL Rule 83 — and return every step, not just the verdict. Use this for any "was that offside" question in either sport. The two rules are structurally OPPOSITE and are routinely conflated, and there are four specific things that get answered wrong: SOCCER: 1. HANDS AND ARMS DO NOT COUNT, for anyone including goalkeepers. Only parts that could legally score are measured, and the boundary is the bottom of the armpit. This tool REFUSES to compute from an arm position rather than guessing where the shoulder was. 2. AN OFFSIDE POSITION IS NOT AN OFFENCE. It becomes one only with involvement in active play. Do not report "he was offside" when the answer is that he was in an offside position and uninvolved. `involvement` is REQUIRED once the geometry makes it decisive — the tool errors rather than assuming, so ask the user what the player actually did, and pass "none" if the answer is nothing. 3. No offside offence direct from a throw-in, goal kick, or corner. Absolute. 4. A DELIBERATE play by an opponent resets it; a deflection or a save does NOT. This is the distinction most arguments turn on. HOCKEY: 5. SKATES decide it. Not the stick, not the body. 6. Since 2021 a skate in the AIR above the blue line is still onside — the line is a plane, and ice contact is irrelevant. BUT this does not apply to tagging up on a delayed offside, where the skate must contact the line. Do not generalise the 2021 change to tag-ups. Input for soccer: positions along the attacking axis in metres, larger being nearer the opponents’ goal line — `attacker`, `ball`, `secondLastDefender`. Any consistent scale works; only the order matters. Optionally `restart`, `foremostPart`, `inOwnHalf`, `involvement`, `lastTouch`. Input for hockey: `rearSkate` in centimetres relative to the LEADING EDGE of the blue line, negative being the neutral-zone side. Optionally `skateOnIce`…

NameTypeReqDescription
attackernumber–SOCCER. Position of the attacker along the attacking axis, larger being nearer the opponents’ goal line. Any consistent scale; only the order matters.
ballnumber–SOCCER. Position of the ball, same scale.
deliberatePlayCriteriaMetarray–SOCCER. Which of IFAB’s five deliberate-play criteria are met. Reported, not scored — there is no pass mark.
foremostPartstring–SOCCER. Which part the attacker position describes. Passing an arm or hand is REFUSED with an explanation: only parts that could legally score count, and the boundary is the bottom of the armpit.
inOwnHalfboolean–SOCCER. A player in their own half cannot be in an offside position.
involvementstring–SOCCER. REQUIRED once the player is in an offside position — the call errors without it rather than assuming. An offside POSITION is not an offence; this is what turns it into one, and "none" is a co…
lastTouchstring–SOCCER. A DELIBERATE play by an opponent resets offside. A deflection, a save, or a rebound off the frame does NOT.
rearSkatenumber–HOCKEY. The trailing skate in centimetres relative to the LEADING EDGE of the blue line — the edge nearer the attacking zone. Negative is the neutral-zone side; positive means it has broken the plane.
restartstring–SOCCER. There is NO offside offence direct from a throw-in, goal kick, or corner. Always ask which restart it was before answering.
secondLastDefendernumber–SOCCER. Position of the SECOND-last opponent, same scale. Usually the last outfield defender, since the goalkeeper is normally the last.
situationstring–HOCKEY. zone-entry (default), or tag-up for clearing a delayed offside. The same skate position can give opposite answers.
skateOnIceboolean–HOCKEY. Since 2021 this does NOT affect a zone entry — a skate above the plane is onside. It is decisive when tagging up, where the skate must contact the line.
sportstringyesWhich rule book. The two are structurally opposite — do not mix them up.
sticknumber–HOCKEY. Ignored, and reported as ignored. Skates decide it.

No output schema declared.

No examples provided.

offside_rule_contrast ~117

Return the structural differences between soccer offside and hockey offside, dimension by dimension. Use this when someone asks how the two compare, or when you are about to reason about one sport using an intuition from the other — which is the commonest way to get either wrong. They differ on what part of the player is measured, when the picture freezes, whether position alone is an offence, what happens at exactly level, what resets the situation, and which restarts are exempt. Takes no arguments. Returns the comparison table.

Input schema present but exposes no named parameters.

No output schema declared.

No examples provided.

Common questions

What is the Sports Rules MCP server?

Sports Rules is an MCP server listed in the public MCP registry as com.gumballtools/sports-rules. Work an offside call through IFAB Law 11 or NHL Rule 83, step by step. This page covers its hosted endpoint (https://sports-rules.gumballtools.com/api/mcp).

Is the Sports Rules MCP server safe to use?

Sports Rules scores 73 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 Sports Rules MCP server expose?

Sports Rules exposes 2 tools: offside, offside_rule_contrast. Their descriptions and schemas cost roughly 1,251 tokens of context every time the server is loaded.

Does the Sports Rules MCP server require authentication?

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

Is the Sports Rules MCP server still maintained?

Sports Rules is still listed as active in the MCP registry. We last reached this channel on 25 September 2026. Those dates come from our own scans of the registry and the channel itself, not from anything the publisher announced.