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

Annotations already declare this as read-only and idempotent. The description adds meaningful behavioral details beyond annotations: newest-first ordering, default limit of 50, no practical maximum, and case-insensitive search over name, email, or external id.

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?

One tight sentence front-loads the core behavior, then packs defaults, offset, and search behavior with zero filler. Every clause earns its place.

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 an output schema present and annotations covering safety, the description supplies the remaining needed context: ordering, pagination defaults, and search scope. Nothing required to invoke this tool correctly 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 coverage is 100%, so the schema already documents all three parameters. The description mostly restates schema content, only adding 'no maximum' and the newest-first ordering. This is useful but doesn't substantially extend the parameter documentation.

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 states a specific verb ('Lists') and resource ('learners'), plus an ordering guarantee ('newest first'). This clearly distinguishes it from singular tools like get_identity and from related list tools like list_members, which target a different concept.

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 listing context with pagination and search semantics, so an agent knows this is the tool for pageable learner enumeration. It doesn't explicitly name alternatives like get_identity or list_members, but for a simple list tool the context is sufficient and no exclusion is needed.

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