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

No annotations are provided, so the description must disclose behavioral traits. It only says 'Fetch' which implies a read operation, but it does not explicitly state it is non-destructive, does not require special permissions, or mention any rate limits or side effects. The description also fails to explain how results are aggregated or ordered. With no annotation safety net, this gap is significant.

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?

The description is a single, focused sentence that immediately states the main purpose and source scope. It is front-loaded with the core action ('Fetch recent discussions') and adds only relevant source details. There is no filler or redundant information, achieving efficient communication.

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?

Given the tool's simplicity and the presence of an output schema, the description covers the basics. However, it does not mention that the tool aggregates across multiple sources, how the results are ranked or limited, or how the 'since'/'until' parameters interact with the 'recent' semantics. An agent might need more context to call it appropriately, but the schema and output schema fill some gaps.

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 all parameters (query, limit, since, until) are already documented in the input schema. The description adds marginal value by equating 'topic' with the query parameter, but it does not explain semantics beyond the schema, such as expected format for dates or limits. The baseline of 3 is appropriate given full schema coverage.

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 clearly states the tool fetches recent discussions about a topic, specifying sources (HN, GitHub, papers). The verb 'fetch' and resource 'discussions' are concrete. It does not explicitly differentiate from siblings like hn_search or search_reddit, but the mention of multiple sources and 'recent' provides enough distinction to be clear.

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?

There is no guidance on when to use this tool versus alternatives such as hn_search, search_reddit, or content_brief. The description only states what it does without any context on conditions that favor it over siblings. No exclusions or scenarios are given, leaving the agent to infer usage.

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