list_users

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

With no annotations, the description carries full burden. It states the tool returns all active and deactivated users in a JSON list with basic profile info, which is transparent about the output. However, it does not disclose any behavioral traits like pagination, rate limits, or performance implications, which could be relevant for a large user list.

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 three short sentences, front-loaded with the core purpose. Every sentence adds value: the first states what it does, the second specifies scope, the third gives return format and usage. No unnecessary words.

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 the tool is a simple list with no parameters and an output schema exists, the description is complete. It mentions the return format and provides a concrete use case. The complexity is low, and the description adequately covers what an agent needs to know to use the tool correctly.

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 zero parameters and coverage is 100%, so the description adds no parameter details. Following the calibration, a baseline of 4 is appropriate when there are no parameters, as the description does not need to provide parameter semantics beyond what the schema offers.

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 it lists all users in the Zulip organization, including active and deactivated. It distinguishes its purpose from siblings like get_user (single user) and other list tools by specifying it returns the full list and is used for finding user IDs or email addresses.

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 explicitly gives a use case: 'Use this to find user IDs or email addresses for filtering messages.' This tells the agent when to use it. However, it does not explicitly mention when not to use it or name alternatives among siblings, though the use case implies differentiation.

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