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get_package

Read-onlyIdempotent

Every known vulnerability in one open source package, most urgent first, with the affected ranges and fixed versions published for that package. Give a version to learn which advisories affect it and the lowest upgrade that leaves every affecting range.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "ecosystem": "<ecosystem>",
      "name": "<name>"
    },
    "name": "get_package"
  }
}

Input Schema

Name	Required	Description	Default
`name`	Yes	The package name, such as lodash, django, org.apache.logging.log4j:log4j-core or golang.org/x/net.
`sort`	No		priority
`limit`	No
`cursor`	No	next_cursor from the previous page.
`version`	No	Optional exact version to check, such as 4.17.20.
`ecosystem`	Yes	npm, PyPI, Maven, Go, crates.io, RubyGems, Packagist, NuGet, Hex or Pub.
`only_affected`	No	With version, list only the advisories that affect it.

Output Schema

Name	Required	Description
`error`	No
`total`	No
`counts`	No
`package`	No
`version`	No	The version check, when a version was given: affected_by, not_comparable, no_fix_listed and upgrade_to.
`matching`	No
`next_cursor`	No	Pass as cursor, with the same arguments, for the next page.
`index_complete`	No
`vulnerabilities`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedNov 10, 2026

TDQS

A3.7/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare the read-only, idempotent, closed-world safety profile, so the bar is lower, yet the description still adds real context: results are ordered 'most urgent first' and include affected ranges and fixed versions. The version mode's extra output ('the lowest upgrade that leaves every affecting range') is behavior the agent could not infer from annotations.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness4/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two tightly packed sentences that front-load the core purpose and follow with the version-mode behavior. The only soft spot is the slightly redundant phrase 'published for that package', which restates the already-stated scope.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

An output schema exists, so return values need not be explained, and annotations cover safety. The description supplies scope, ordering, and version-mode behavior, which is enough for a 7-parameter tool; only pagination behavior and sibling routing are left unaddressed.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

At 71% schema coverage, the schema already documents name, version, cursor, ecosystem, and only_affected. The description meaningfully expands the version parameter beyond 'Optional exact version to check' by explaining it yields both affecting advisories and the lowest safe upgrade, and it hints that the default ordering is urgency-based. It says nothing about limit, cursor paging, or only_affected beyond what the schema states.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource: 'Every known vulnerability in one open source package', plus the returned fields (affected ranges, fixed versions). This is clearly scoped to a single package, implicitly distinguishing it from get_vulnerability (one advisory) and check_stack (many packages), but it never names an alternative explicitly.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Provides one conditional usage instruction — 'Give a version to learn which advisories affect it' — which tells the agent when to pass the version parameter. It stops short of stating when to prefer get_vulnerability, check_stack, or top_priority instead, or when not to use this tool.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

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