course_updates

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

Annotations already declare readOnlyHint, idempotentHint, openWorldHint, and destructiveHint=false, so the safety profile is covered. The description usefully adds what the result contains (changed modules, new announcements, notifications) and the accepted time formats, but says nothing about auth requirements, rate limits, or result limits beyond that.

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 sentences, front-loaded with the scope of changes, then the parameter format, then a plain-language restatement of the use case. The final sentence is somewhat redundant with the first two but functions as a memorable anchor, so little is wasted.

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?

An output schema exists, so return-value shape needn't be explained, and the description covers scope and the main parameter format. The remaining gap is the unexplained course_id parameter, which an agent must guess at (per-course scoping vs. all courses).

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 0%, so the description carries the burden here. It fully documents 'since' (ISO-8601, Unix timestamp, relative values like '24h'/'2d'/'yesterday'), which is valuable since the schema has no description for it. But 'course_id' is never mentioned, and the schema offers no help either — so half the parameter surface is undefined.

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 gives a specific verb+resource ('what changed in the student's courses') and enumerates the change categories covered: module settings/files/grades, new announcements, and Moodle notifications. That scope implicitly separates it from narrower siblings like recent_announcements, but the description never names or contrasts those siblings explicitly.

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 closing line 'Answers "what changed since yesterday?"' situates the tool in a real use case, which is implied guidance. However, there is no explicit when-to-use vs. when-not, and no routing to alternatives such as recent_announcements or daily_briefing, which overlap on change/notification information.

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