substack (pmcostadev/substack) is an MCP server listed on the M8ven Trust Index. M8ven has not graded it yet. No publisher has claimed this listing.

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D
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56/100

substack

MCP server for Substack with Streamable HTTP transport. 27 tools: drafts, publish, subscribers, analytics, Notes, comments, reader. Deployed on Vercel.

→ pmcostadev/substack· listed on github_repo_search

Caution. Specific findings reduced this grade. They are listed on the page. Grades reflect the full trust pyramid: code, verification depth, and reputation. New projects cap at C until adoption is earned.

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⚡ Live Monitored: not connected

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Who stands behind it

pmcostadev

Source: github_repo_search

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Install from

GitHub

The grade above is for the source repository. Registries can serve a different version, so we mark the ones we were not able to read.

// key findings
🚨
Known vulnerabilities in dependencies: 3 critical, 12 high
Affects packages this MCP installs at runtime. Upgrade or remove the affected dependency.
🔐
You'll be asked for 1 credential: SUBSTACK_SESSION_TOKEN
These are read from process.env at runtime. Make sure you trust where they’ll be sent.
// known CVEs in dependencies3 critical12 high6 medium9 low

Disclosed vulnerabilities in this server's declared npm dependencies (via OSV). Whether each is reachable depends on the installed versions.

criticalnext@15.3.3GHSA-2xp9-vwfh-vxw4

Next.js: Unauthenticated Remote Code Execution in Image Optimization API when AVIF files are used

criticalnext@15.3.3GHSA-9qr9-h5gf-34mp

Next.js is vulnerable to RCE in React flight protocol

criticalnext@15.3.3GHSA-p293-qw3h-jr36

Next.js: Unauthenticated Remote Code Execution on windows-hosted servers

highnext@15.3.3GHSA-267c-6grr-h53f

Next.js has a Middleware / Proxy bypass in App Router applications via segment-prefetch routes

highnext@15.3.3GHSA-26hh-7cqf-hhc6

Next.js has a Middleware / Proxy bypass in App Router applications via segment-prefetch routes - Incomplete Fix Follow-Up

Depend on this server? Get alerted when its CVEs change.Watch this server free →
// environment variables
To run this server yourself, you supply these values. They go in your own MCP client configuration and stay on your machine. The secret label means the value is sensitive, not that the server mishandles it.
configSUBSTACK_MCP_LOG_LEVEL
🔐 secretSUBSTACK_SESSION_TOKENYour substack.sid cookie from browser devtools
// quality suggestions

License file

No license file

Add a LICENSE file (MIT, Apache-2.0, etc.).

Tests exist

No test files found

Add tests that exercise each declared tool.

Production dependencies are patched

3 critical, 12 high severity in production deps — next@15.3.3 (critical), next@15.3.3 (critical)

Run npm audit fix, or upgrade the affected packages to a non-vulnerable version.

Claim the listing to review these findings one by one and send us a correction where you disagree, straight to the team. Claiming also means we tell you when the grade moves, and reach you first if we find anything urgent.

// full audit trail
The findings above are the summary. The full trail, every check we ran, each deduction, the network hosts observed and the dependency advisories, goes to verified publishers, along with an alert whenever a new one lands. Verified publishers can also review each finding and dispute it in one click. Publisher corrections have sharpened several of our checks this month, because the maintainer knows the codebase better than any scanner.
// improvement guidance — verified publishers only
We have 3 concrete improvements we can share with the publisher of this MCP. Each comes with specific guidance to raise the trust score.
// embed badge in your README
[![M8ven Verified](https://m8ven.ai/badge/mcp/pmcostadev/substack?variant=verified)](https://m8ven.ai/mcp/pmcostadev/substack)
Shows verification status without the grade. Want the grade badge instead? Remove ?variant=verified from the URL.
commit: 7f5c0ac6bfe1a905887420c0e92bbf7a51773f6a
code hash: 9e4878fc3b699e0fc7af7d401e93a05a6cee63005a704f143125d9b555a26e99
view raw JSON →
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