batch_get_users_by_ids

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

With no annotations, the description carries the full burden. It only says the tool returns a dictionary and provides an argument example. It does not disclose how invalid IDs are handled, whether results are partial, authentication or rate-limit requirements, or any other behavioral traits beyond the basic fetch.

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 concise and well-structured with Args and Returns sections. It includes an example and no irrelevant details, making it easy to parse.

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?

The tool is simple, but given the absence of annotations and an output schema, the description is incomplete. It does not specify the structure of the returned dictionary, behavior on nonexistent IDs, or any guidance on when to use it versus sibling tools, leaving important gaps for an agent.

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 only requires a string user_ids, but the description adds the comma-separated format and a concrete example ('1234567890,1234567891,1234567892'), which significantly clarifies how to construct the argument.

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's function: 'batch get user information by user ID'. It identifies the specific resource (users) and the batch scope via multiple IDs, which distinguishes it from sibling get_user_info_by_username that uses a single username.

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 batch usage by specifying a comma-separated list of user_ids, but it does not explicitly state when to choose this tool over alternatives or exclude scenarios where other tools are more appropriate. No comparison with siblings is provided.

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