Skills/npm/just-signal-mcp

just-signal-mcp@1.3.0

VERIFIED

Publisher claims: "Keyless MCP for Just Signal: live quotes, report publishing, scorecard, and Chophouse panel grades." Observed in sandbox: no network, touches nothing outside the project, writes no memory.

Registry npm (MCP server) · listed in the official MCP RegistryPublisher ou-reports · publishing for 131 daysInstalls 0Last detonated 38 h ago
$claude mcp add just-signal-mcp -- npx -y just-signal-mcp
WatchReport an issue

Coverage

Server started and answered tools/list.
Tested
MCP initialize and tools/list · every tool description, for hidden instructions · every file read, file written and host contacted by what ran
Not tested
what the tools do when called with real credentials

Before you give it your token

It will ask for
JS_PUBLISH_TOKENConfiguration, not credentials: JS_BASE_URL
Where it talks to
ou-reports.com (its own)Also gstatic.com, yahoo.com — not the publisher's domain; check what for before connecting.
What the honeypot saw
no credential files read · no network
What we could not test
what the tools do when called with real credentials

Connect it with a scoped credential, under the guard, and read the third-party hosts first. The code names gstatic.com, yahoo.com as well as its own vendor. The guard injects JS_PUBLISH_TOKEN only into requests to ou-reports.com (and its subdomains) and refuses the rest.

$vet-skills run --secrets JS_PUBLISH_TOKEN=ou-reports.com -- npx -y just-signal-mcp

Never paste a credential into a chat, a ticket or a report, including ours. How the guard holds it.

Is [email protected] safe to install?

KillerSkills ran it in the KillerSkills honeypot sandbox (2 scenarios) on 2026-11-13 and scored it 90/100 (Verified). It did what it claims and nothing else we could detect: no undeclared network egress, no credential reads, no persistent instruction writes. Summary: no network, touches nothing outside the project, writes no memory.

Behavior trace

Honeypot run · 25 s · 2 scenarios · 0 deviations
t+CategoryObserved action
0.0sprocessno install scripts in bundle
5.1sprocessdependency install exit 0
25sclaimed5 tools: get_stock_quote, publish_report, list_reports, get_scorecard, get_panel_grade
25sprocessscript backend runs setup only
25sprocessno install scripts to re-run

Static findings

HIGH
URL with embedded credentialslib.js:153 · URL with embedded credentials — may be phishing or credential leaking…link rel="preconnect" href="https://fonts.gstatic.com" crossorigin> <link href="https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Orbitron:wght@400;700;900&family=Syne:wght@300;400;60…Fix: Stop enumerating or reading credential locations; take secrets from a declared environment variable the user sets on purpose.
AST07

No other findings across 713 lines in 5 files.

Cost to the agent

Instructions loaded
≈76 tok
1 file · 5 in bundle
Tool list per prompt
≈1,001 tok
5 tools · 200 per tool
Handshake
437 ms
launch to tools/list, stdio
Undocumented tools
0
description under 20 chars · avg 321

Tokens estimated at four characters each. The tool list is re-read by the agent on every turn, so it is the number to compare between servers that do the same job: ranked across the index.

Known vulnerabilities

No advisories in OSV for just-signal-mcp@1.3.0 as of 38 h ago. This is the package itself, not its dependencies.