Substack (postcli) MCP Server
@postcli/substack
npm
v0.2.0
Published by @postcli — no publish provenance, so origin is unverified, but the source is public: the repository link below is self-declared yet readable, so you can inspect the code before adopting it.
Substack plugin for PostCLI - read posts, publish notes, manage your Substack from the terminal
The grade answers one question — how safe is this server for you to adopt — so it is computed in two auditable stages. Nothing below is an opinion or an LLM's guess; every line is a real term the deterministic engine applied, and the same input always yields the same number.
1. Threat score — 100 − 0 = 100. What the published surface and source actually contain:
The deterministic scan raised no scored threat in the surface it inspected — the threat score stayed at 100. Capability observations and advisory notes are recorded but never lower it.
2. Client adoption risk — 100 − 7 = 93. Three small, subtract-only factors that reflect your risk in adopting it — a clean scan proves less on a powerful, unverified or barely-inspectable package, so the grade says so plainly:
| Points | Adoption-risk factor |
|---|---|
| −6 | capability blast radius (high) — client exposure if the model is manipulated |
| −1 | publisher verification (public source) — no provenance, but the source is public and inspectable |
Capability observations and info notes are shown under Findings but never scored.
Open any row's finding below for the file, line and evidence behind a deduction.
Findings 9
high Shell/command execution in server code (dist/cli/chrome-cookies.js)MTC-SRC-002
In the server's implementation (`dist/cli/chrome-cookies.js:1`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.
Evidence: port { execSync } from 'child_process'; import { existsSync } from 'fs'; import { join } from 'path'; import { homedir }
Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.
Location: server dist/cli/chrome-cookies.js
high Shell/command execution in server code (dist/cli/tui/App.js)MTC-SRC-002
In the server's implementation (`dist/cli/tui/App.js:35`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.
Evidence: import('child_process').then(({ execFile }) => { const cmd = process.platform === 'd
Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.
Location: server dist/cli/tui/App.js
high Shell/command execution in server code (dist/cli/tui/views/Comments.js)MTC-SRC-002
In the server's implementation (`dist/cli/tui/views/Comments.js:94`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.
Evidence: }`; import('child_process').then(({ execFile }) => { const cmd = process.platform === 'darwi
Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.
Location: server dist/cli/tui/views/Comments.js
high Shell/command execution in server code (dist/cli/tui/views/Feed.js)MTC-SRC-002
In the server's implementation (`dist/cli/tui/views/Feed.js:30`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.
Evidence: import('child_process').then(({ execFile }) => { const cmd = process.platform === 'd
Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.
Location: server dist/cli/tui/views/Feed.js
high Shell/command execution in server code (dist/cli/tui/views/Notes.js)MTC-SRC-002
In the server's implementation (`dist/cli/tui/views/Notes.js:98`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.
Evidence: }`; import('child_process').then(({ execFile }) => { const cmd = process.platform === 'darwi
Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.
Location: server dist/cli/tui/views/Notes.js
high Shell/command execution in server code (dist/cli/tui/views/PostList.js)MTC-SRC-002
In the server's implementation (`dist/cli/tui/views/PostList.js:47`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.
Evidence: import('child_process').then(({ execFile }) => { const cmd = process.platform === 'd
Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.
Location: server dist/cli/tui/views/PostList.js
high Shell/command execution in server code (dist/cli/tui/views/Profile.js)MTC-SRC-002
In the server's implementation (`dist/cli/tui/views/Profile.js:10`): Spawning a shell/process is command-execution capability; with unsanitized tool input it is command injection / RCE. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.
Evidence: }`; import('child_process').then(({ execFile }) => { const cmd = process.platform === 'darwi
Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.
Location: server dist/cli/tui/views/Profile.js
medium Hardcoded egress to an external endpoint (dist/cli/commands/auth.js)MTC-SRC-003
In the server's implementation (`dist/cli/commands/auth.js:122`): A hardcoded outbound call to a fixed external host inside server code is a classic exfiltration/telemetry channel — especially paired with reads of local data. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.
Evidence: const loginRes = await fetch('https://substack.com/api/v1/email-login', { method: 'POST', headers: { 'C
Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.
Location: server dist/cli/commands/auth.js
medium Hardcoded egress to an external endpoint (dist/lib/substack.js)MTC-SRC-003
In the server's implementation (`dist/lib/substack.js:236`): A hardcoded outbound call to a fixed external host inside server code is a classic exfiltration/telemetry channel — especially paired with reads of local data. This is read from the code itself — not from the tool description — so a poisoned server cannot hide it behind honest-looking metadata.
Evidence: const res = await fetch('https://substack.com/api/v1/reader/feed', { headers }); return res.ok; }
Fix: Review this call path: confirm it never receives unsanitized tool input, constrain it, or remove it. Treat a server whose code reaches these sinks as high-capability regardless of what its tools claim.
Location: server dist/lib/substack.js
What this scan could not see
- No tools were enumerated, so prompt-injection, capability and toxic-flow analysis had no tool surface to inspect. To grade a package’s real runtime tools, scan the running server: --command "npx -y <package>".
Versions 1
Scan history per published version. The engine is deterministic — the same version always yields the same score, so a changed score means the package itself changed.
| Version | Score | Findings | Engine | Scanned |
|---|---|---|---|---|
v0.2.0 latest |
A 93/100 | 9 | 1.13.0 | 2026-09-07 |
Embed this score
Show this server's live Trust Score in your README, docs or website. The badge is served straight from the registry and updates automatically after every rescan — no API key needed. It links back to this page, so anyone who sees the grade can also read the findings behind it instead of taking a number on faith.
Verify this score yourself
The score above is reproducible: the same package version always yields the same result. Run it locally or over the free API — no account, no LLM, fully deterministic.
npx mcptrustchecker scan @postcli/substack --onlineOther implementations of Substack 4
Independent packages implementing the same tool, scanned with the same engine. Compare all 5 side by side →
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