get_user_posts

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

Annotations already declare readOnlyHint and openWorldHint, and the description reinforces this with 'Read-only' and 'works anonymously.' It also adds meaningful context by listing the returned post fields and describing the 'after' pagination cursor, which is not visible in annotations or the output schema.

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 compact, front-loaded with the core purpose, and every sentence earns its place by adding purpose, behavioral context, or usage alternatives. It avoids redundant restating of schema details and remains highly scannable.

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 tool with five parameters and no output schema, the description provides a complete operational picture: what it returns, how paging works, its authentication posture, and how it fits among sibling tools. This is sufficient for an agent to select and invoke the tool correctly without further ambiguity.

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 schema description coverage is 100%, so every parameter is already documented in the schema itself. The tool description adds useful context around sort and pagination but does not need to compensate for missing schema detail; therefore, a baseline score of 3 is appropriate.

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 gets posts submitted by a specific user and identifies the resource and supported sort/time-filter capabilities. It also distinguishes itself from sibling tools like get_user_comments and get_user_info, making its purpose 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 explicit guidance on when to use this tool versus alternatives: use get_user_comments for comments, get_user_info for profile stats, and search_reddit or browse_subreddit for subreddit searching. This direct exclusionary guidance is strong and actionable.

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