list_users

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

With no annotations, the description carries the full burden of behavioral disclosure. It only states 'List users', which implies read-only but does not mention potential pagination, required permissions, or any other side effects or return characteristics. The portal/project scoping is the only behavioral nuance disclosed.

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 redundant words. It communicates both the action and the scoping in an efficient manner.

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's simplicity (one optional parameter, no output schema), the description covers the core purpose and scope adequately. However, it lacks any mention of return value structure or pagination, which would be helpful for an agent, so it is not a perfect 5.

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 covers the project_id parameter fully, including its optionality for portal-level, and the tool description reinforces this by mentioning 'portal or project'. No additional parameter-level detail is added beyond the schema, so the 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 uses a specific verb+resource construction, 'List users in a portal or project', clearly identifying the resource and scope. This distinguishes it from sibling tools like list_portals and list_projects, which operate on different resources.

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 clear context that the tool can be used for portal-level or project-level user listing, and the optional project_id parameter aligns with this dual scope. However, it does not explicitly state when not to use it or mention alternatives, though no overlapping user-listing siblings exist.

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