hackernews_userGet a Hacker News user's profile data including karma, about text, creation date, and submission count. Use this to retrieve account statistics for any username.
A Hacker News user's karma, about text, creation date and submission count. Use hackernews_submissions or hackernews_comments instead to list what they posted.
| Name | Required | Description | Default |
|---|---|---|---|
| username | Yes | Hacker News username, e.g. pg |
Changes observed during successful MCP inspections.
v0.0.0-developmentDoes the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare the operation read-only and open-world, and the description adds useful context by enumerating the returned fields and warning that it does not list posts. It does not cover edge cases like nonexistent usernames or rate limits, but the safety profile is already carried by annotations.
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 short sentences convey the tool's purpose and direct the agent to the appropriate sibling tools. The distinguishing information is front-loaded, with no wasted words.
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 one-parameter, read-only profile lookup, the description is complete: it states what data is returned and when to use an alternative tool instead. No output schema exists, but the listed fields sufficiently describe the return value for an agent to select and invoke the tool correctly.
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 100%, and the only parameter, username, is documented with a concrete example ('e.g. pg') in the schema. The tool description adds no additional parameter-level guidance, so the baseline of 3 applies.
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?
The description specifies the resource and the fields returned (karma, about text, creation date, submission count), so an agent can infer this is a profile metadata lookup. It lacks an explicit action verb like 'get' or 'fetch', but the resource and data are specific. The second sentence also differentiates it from the submission/comment listing siblings.
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 description explicitly directs the agent to use hackernews_submissions or hackernews_comments when the goal is to list what a user posted. This is a clear when-not condition, and the opening sentence makes the intended use case (accessing profile metadata) unambiguous.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.