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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds real value beyond that: it discloses the exact returned fields and the security-relevant constraint that 'api_key values are never returned', which an agent cannot infer from the structured data.

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?

Three compact sentences that front-load the purpose, then the returned fields, then the security note. The trailing 'GET /users' endpoint is mildly redundant but consumes almost no space and causes no harm.

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?

With no output schema, enumerating the returned fields and the api_key exclusion is exactly the compensation needed, and pagination is handled by the schema's next_page hint in the page parameter. An agent has enough to call it correctly; only explicit alternative-routing guidance is missing.

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?

Schema description coverage is 100%, so page, per_page, email and including_inactive are fully documented in the schema itself. The description says nothing additional about these filters; per the rubric baseline, 3 is correct when the schema does the heavy lifting.

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?

States a specific verb ('List') and resource ('users of the Pipeline CRM account'), and enumerates the returned fields (id, name, email, team, admin flag). This clearly separates it from the sibling get_user (single user) and other list_* tools that target 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?

Provides a downstream usage note—'Use the ids as owners of deals, people and companies'—which implies why an agent would call this. However, it never states when to prefer this over get_user or list_people, nor any preconditions, so the usage guidance is implied rather than explicit.

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