Get User Posts

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

Annotations already cover readOnly/idempotent/destructive safety. The description adds meaningful behavioral context by stating that retweets and replies are excluded, which affects the expected result set. It does not mention pagination or error behavior, but the bar is lower given 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?

The description is a single, front-loaded sentence with no filler. It states the action, resource, and key filter in under 15 words, making it highly concise and structured.

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 simple read-only tool with complete schema coverage and annotations, the description sufficiently covers the main scope and exclusions. It lacks explicit mention of ordering or error handling, but these are not required given the tool's simplicity and the absence of an output schema obligation.

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% with descriptive parameter documentation. The description adds no additional parameter-level detail beyond what the schema already provides, 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 uses a specific verb ('Fetch') with a clear resource ('posts from a user's timeline') and adds explicit exclusions ('Excludes retweets and replies'). This clearly distinguishes it from sibling tools like x_get_my_timeline (which is likely for the authenticated user's home timeline) and x_search_posts (which searches across posts).

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 implies usage for fetching a user's posts by username, but does not explicitly state when to use it over alternatives. No exclusions or alternative tool references are provided, leaving the agent to infer from sibling names.

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