get_posts

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

No annotations are provided, so the description carries the burden. It states this is a retrieval operation with no side effects, and outlines the available query variants. It does not mention response format or potential limitations, but for a simple read-only tool the description is reasonably transparent.

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, well-structured sentence that front-loads the primary purpose ('Get posts') and efficiently covers all three modes. There is no filler or redundant information.

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?

This is a simple read-only tool with two optional parameters, no output schema, and no nested objects. The description is sufficient for an agent to understand the tool's capabilities and primary use cases, though it omits details like response format or pagination, which are not critical for a basic JSONPlaceholder endpoint.

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 already describes both parameters (id and userId) with 100% coverage. The description essentially paraphrases the schema's semantics by mentioning retrieval by ID and filtering by user ID. It adds no new or deeper meaning beyond what the schema provides.

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 retrieves posts from JSONPlaceholder and explicitly lists the three retrieval modes: all posts, by ID, or by user ID. The verb 'get' plus resource 'posts' distinguishes it from sibling tools like get_users and get_comments.

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 gives clear context on when to use the tool: whenever posts are needed, with optional filtering by ID or user. It does not explicitly mention alternatives (e.g., 'for comments use get_comments'), but the sibling names make the appropriate use obvious.

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