Look up a package across npm, PyPI, Cargo, Go, Maven, NuGet, or RubyGems via deps.dev to get versions, latest release, licenses, links, and deprecation status.
Look up a package across npm, PyPI, Cargo, Go, Maven, NuGet, or RubyGems via deps.dev. Returns versions, latest, licences, links, and deprecation.
| Name | Required | Description | Default |
|---|---|---|---|
| name | Yes | ||
| version | No | ||
| ecosystem | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already cover the safety profile (readOnly, idempotent, non-destructive, open-world), so the bar is lower. The description adds genuinely useful context beyond them: the upstream data source (deps.dev) and an enumeration of returned fields, which matters because no output schema exists. It omits not-found/error behavior for unknown packages, keeping it at 4.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two tight sentences with zero filler: the verb, ecosystem coverage and source come first, the payload second. Every clause carries information an agent cannot get from the schema.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a read-only lookup with no output schema, describing the returned fields is the key compensation, and it does that. The remaining shortfall is the optionality and semantics of the version parameter, which is undocumented in both schema and description.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 0%, so the description carries the burden, and it partially does: the ecosystem list mirrors the enum values and "versions, latest" gestures at the version parameter. But it never says version is optional or that omitting it yields the latest, nor how name is scoped per ecosystem — a notable gap given zero schema documentation.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb and resource ("Look up a package") plus the backing source (deps.dev) and enumerates all seven supported ecosystems, so scope is unambiguous. It also lists what comes back (versions, latest, licences, links, deprecation). It stops short of naming the nearest siblings (get_version, search_packages) to draw the boundary, so a 4 rather than a 5.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Usage is only implied: the returned-fields list hints that you call this when you need package metadata rather than dependency graphs or vulnerabilities. With nine siblings including get_version, search_packages and license_check, no explicit when-to-use-this-vs-that guidance is given, leaving real ambiguity for an agent choosing between them.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.