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

The destructiveHint annotation only signals a mutation; the description goes further by labeling it a WRITE, disclosing the deliberate omission of password/admin-flag fields, and naming the backing endpoint. It still says nothing about duplicate-email behavior, auth requirements, or what failure looks like, so it is helpful but not complete.

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 short clauses, front-loaded with the WRITE marker and the account type, with the endpoint as a compact trailing reference. No filler.

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?

For a create tool with no output schema and only a single destructiveHint annotation, the description covers the essential design (no password, self-service registration) and the sibling-distinguishing purpose. It omits error/duplicate handling and post-creation behavior, which is a minor gap given the rich schema.

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 the schema already documents all seven parameters including the nested fields object. The description reinforces the role of send_registration_email but adds no format or usage detail beyond the schema, so the baseline 3 applies.

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 and resource ('WRITE: create a learner account') and names the API endpoint, which tags it clearly as distinct from learnworlds_update_user, learnworlds_get_user, and the enrollment/group siblings.

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?

Gives actionable how-to guidance ('Deliberately no password or admin flag — set send_registration_email so the learner sets their own password'), which tells the agent the intended flow. It does not explicitly name update_user or state when-not to use this tool, so it stops short of full alternative routing.

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