Hacker News thread

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety and external-fetch behavior are covered. The description usefully confirms the scope is a thread plus its top comments, but says nothing about rate limits, failure modes for bad IDs, or how the comment tree is shaped.

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?

A single compact sentence with the core action front-loaded and no filler. There is little structure to speak of, but nothing is wasted.

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 could say more about what the returned thread looks like (nested comments, truncation behavior). Annotations cover the safety profile and the schema covers every parameter, so it is adequate but not fully self-sufficient.

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 all three parameters carry their own descriptions and bounds, so the schema does the heavy lifting. The tool description adds nothing about the meaning of 'depth' or 'max_comments' beyond what is already documented.

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 concrete verb ('Read') and resource ('a Hacker News story or Ask HN post with its top comments'), so the agent knows exactly what it returns. It does not distinguish itself from siblings like hackernews_search or hackernews_stories, leaving the agent to infer the boundary.

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 trailing clause 'to summarise what people are saying' implies a use case, but there is no explicit when-to-use guidance, no exclusion rules, and no named alternative for fetching a single item vs. searching or listing stories.

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