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

Annotations already declare readOnlyHint=true, so the safety profile is covered. The description adds genuinely new behavior: newest-first ordering, 50-per-page pagination, and the fact that it doubles as a cheap connectivity/credential check. It does not mention total counts or whether further pages exist, but it goes well beyond the annotation.

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?

Two sentences, zero filler. The listing scope, ordering, page size, and returned fields are front-loaded, with the credential-check tip and the underlying endpoint following compactly.

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 filterable read-only list tool with no output schema, the description supplies ordering, page size, returned field set, one useful use case, and the backing endpoint. Combined with annotations and a fully documented schema, an agent has everything needed to call it 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?

Schema description coverage is 100%, so all three parameters (page, access, categories) are already documented with their semantics. The description repeats access values (paid/free/draft) and mentions filtering by categories, adding little 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 ('List the school's courses') and immediately enumerates the returned fields (title, price, access, categories, author). The plural 'List' plus the school-wide scope cleanly distinguishes it from the singular learnworlds_get_course and from user-scoped siblings like learnworlds_list_user_courses.

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 a concrete use case, 'a cheap way to confirm the credentials work,' which tells the agent when this is a good low-cost call. No explicit when-not or named alternative (e.g., use get_course for a single course), so it stops short of full routing guidance.

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