find_packagesFind nixpkgs packages by exact, prefix, or partial name and see each package's status: failed, outdated, up to date, or vulnerable.
Find nixpkgs packages by name (exact, then starting with, then containing the query), each with its status: failed, outdated, up to date, vulnerable.
| Name | Required | Description | Default |
|---|---|---|---|
| limit | No | At most this many results (default 20). | |
| query | Yes | Part of a name. |
Changes observed during successful MCP inspections.
v0.3.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint and openWorldHint, so the description only needs to add context. It adds the result ordering rule and the fact that each result carries a status label, but says nothing about truncation behavior beyond the schema's limit, case sensitivity, or how statuses are computed.
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?
One dense sentence with no filler; the match strategy and return payload are front-loaded where an agent will read them.
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?
With no output schema, the description usefully enumerates what comes back (name plus status categories). For a two-parameter read-only search this is largely sufficient; only edge-case behavior like empty results or case sensitivity is unstated.
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 coverage is 100%, so baseline is 3; the description earns an extra point by explaining the matching precedence for 'query' (exact → starts-with → contains), which the schema's 'Part of a name' does not convey. The 'limit' parameter is left to the schema, which documents it fully.
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 (find), a specific resource (nixpkgs packages), and even the match strategy and returned fields. It does not explicitly distinguish itself from the sibling 'package' tool (likely a single-package detail lookup), so it falls just short of 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?
The match ordering (exact, then prefix, then contains) implies how to phrase a query, which is implicit usage guidance. However, there is no explicit statement of when to use this versus 'package' or 'needs_attention', and no exclusions or prerequisites.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.