get_user_activity

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

No annotations are provided, so the description carries the full burden. It merely states the action but does not disclose important behaviors such as error handling (e.g., nonexistent user), rate limits, ordering of results, or pagination beyond the 'limit' parameter. This lack of detail limits an agent's ability to predict tool behavior.

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 sentence of 8 words, making it extremely concise. However, it could be better structured to include additional context without becoming verbose. The brevity is a strength, but it sacrifices some necessary detail.

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 that an output schema exists (not shown here), the description need not detail return values. However, the tool has 3 parameters and no annotations, and the description fails to cover behavioral aspects like error states or default ordering. It provides the minimum viable context to understand the tool's primary function but leaves 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?

The input schema has 100% coverage, with each parameter described. The description adds the word 'recent', implying chronological ordering, which is not in the schema. However, it does not elaborate on parameter interactions or constraints beyond what the schema provides. Overall, the description adds marginal value over the schema.

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 a user's recent posts and/or comments, which distinguishes it from siblings like 'get_subreddit_posts' and 'get_user_profile'. The verb 'Fetch' and resource 'posts and/or comments' are specific and unambiguous.

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 provides no explicit guidance on when to use this tool versus alternatives. While the purpose is clear, there is no mention of when it should be preferred over sibling tools like 'get_user_profile' or 'get_subreddit_posts'. The context of recent activity is implied but not explicitly contrasted.

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