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HALLUX

by blvkware.dev · remote · no sign-in to list tools · v0.1.0 · published by dev.blvkware

Check that a package, module or DOI exists before an agent installs, imports or cites it.

Changes · 4
CompareRegistry entry

4 tools: 4 change things.

Scanned Oct 21, 2026

2 checks matched something in the tool definitions. No finding is not a safety guarantee. How the checks work.

claude mcp add --transport http hallux https://api.blvkware.dev/hallux/mcp

Findings

Matches of fixed checks, with the text they matched.

2 warn
  • Warnhallux_check_command

    The server marks "hallux_check_command" read-only (readOnlyHint: true), and its own name, description or input give the class "write".

    Matched text

    annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The description's first verb is "call": a word for a change.

    What this check looks for
  • Warnhallux_check_manifest

    The server marks "hallux_check_manifest" read-only (readOnlyHint: true), and its own name, description or input give the class "write".

    Matched text

    annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The description's first verb is "call": a word for a change.

    What this check looks for

Tools

Open a tool for its reasons and full description. Descriptions are the publisher's own words, shown as they are.

4 tools

Changes things 4Claude Code: ask
  • hallux_checkDoes this identifier actually exist?No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.
    Description, as the server wrote it
    Does this identifier actually exist? Call before acting on any name you recalled rather than read: a package to install, a module to import, a DOI to cite. Returns one of: exists, deprecated, absent, phantom, squat, unknown. exists - proceed deprecated - proceed, but use `successor` absent - not in the registry. Do not proceed phantom - does not exist AND models repeatedly invent it. Do not proceed squat - was invented by models, then registered by someone. Treat as hostile unknown - could not verify. Never treat this as permission Live namespaces: cite.doi, pkg.crates, pkg.go, pkg.maven, pkg.npm, pkg.nuget, pkg.pypi. An unsupported namespace returns `unknown`, never an error, so it is safe to ask.

    Annotations the server declares

    • destructiveHint: false
    • idempotentHint: true
    • openWorldHint: true
    • readOnlyHint: true
    • title: Check identifiers
  • hallux_check_commandCall this BEFORE running any command that installs a dependency: npm, yarn, pnpm, bun, pip, uv, poetry, pipx, cargo, go get, dotnet add package, nuget.1 finding

    Why it is in this group

    • The description's first verb is "call": a word for a change.
    • The input takes a statement or command to run (input.command), which can change anything it can reach.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.

    Findings

    • Warn

      The server marks "hallux_check_command" read-only (readOnlyHint: true), and its own name, description or input give the class "write".

      Matched text

      annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The description's first verb is "call": a word for a change.

      What this check looks for
    Description, as the server wrote it
    Call this BEFORE running any command that installs a dependency: npm, yarn, pnpm, bun, pip, uv, poetry, pipx, cargo, go get, dotnet add package, nuget. Language models invent plausible package names that have never existed, and attackers register those names because they can predict them. Installing one runs attacker code. You cannot tell the difference by looking at the name, which is why this check exists. Pass the command exactly as you intend to run it. The identifiers are extracted for you. If the result says BLOCK, do not run the command. Use the `successor` if one is given, otherwise tell the user what was found and stop.

    Annotations the server declares

    • destructiveHint: false
    • idempotentHint: true
    • openWorldHint: true
    • readOnlyHint: true
    • title: Check an install command
  • hallux_check_manifestCall this after writing or editing a dependency file, and before committing it.1 finding

    Why it is in this group

    • The description's first verb is "call": a word for a change.
    • The server marks it read-only (readOnlyHint: true), but an annotation never lowers a class.

    Findings

    • Warn

      The server marks "hallux_check_manifest" read-only (readOnlyHint: true), and its own name, description or input give the class "write".

      Matched text

      annotations: {"readOnlyHint":true,"destructiveHint":false,"idempotentHint":true,"openWorldHint":true}; The description's first verb is "call": a word for a change.

      What this check looks for
    Description, as the server wrote it
    Call this after writing or editing a dependency file, and before committing it. Supported: package.json, requirements.txt, pyproject.toml, Cargo.toml, go.mod. Checks every dependency in one pass, including dev and optional groups, which is where an invented name usually arrives.

    Annotations the server declares

    • destructiveHint: false
    • idempotentHint: true
    • openWorldHint: true
    • readOnlyHint: true
    • title: Check a dependency file
  • hallux_watchRegister identifiers for notification when their verdict changes.No findings

    Why it is in this group

    • Nothing in its name or description says what it does, so it is counted as a write.
    Description, as the server wrote it
    Register identifiers for notification when their verdict changes. The transition that matters is phantom to squat: a name models invent that somebody then registers. Use this for a dependency that came back `absent` or `phantom` and that the user intends to use anyway, or for a set of dependencies worth monitoring. Delivered by signed webhook to a URL you supply.

    Annotations the server declares

    • destructiveHint: false
    • idempotentHint: false
    • openWorldHint: true
    • readOnlyHint: false
    • title: Watch for verdict changes

This is not a safety rating, and no finding is not a safety guarantee. The groups and findings come from fixed checks of the tool definitions the server returned on the date shown, not from its code or what it does when called. How the checks work.

Install

Pinned to version 0.1.0. Values in angle brackets are yours to fill in.

claude mcp add --transport http hallux https://api.blvkware.dev/hallux/mcp

Run in a terminal.

Claude Code permissions

Allow the reads, ask before a change, deny the deletes. Paste into .claude/settings.json.

.claude/settings.json
{
  "permissions": {
    "allow": [],
    "ask": [
      "mcp__hallux__hallux_check_command",
      "mcp__hallux__hallux_check",
      "mcp__hallux__hallux_check_manifest",
      "mcp__hallux__hallux_watch"
    ],
    "deny": []
  }
}

Tools that only read are allowed, tools that change things ask first, tools that delete or cancel are denied. It assumes the server is installed as hallux. Review it before you use it.