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

Annotations already cover the read-only safety profile. The description adds genuine value by disclosing what the return does and does not contain (tracking rules yes, watch-percentage and deadline no), which goes beyond the annotations. Minor gap: no note on output shape or size, though an output schema exists.

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?

Front-loaded with the core statement, then the comparison to get_course_contents. Efficient overall, though the trailing clause on vod modules runs long and could be tightened without losing meaning.

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 one-param read tool with an output schema and clear annotations, the description is complete: it explains what is returned, what is not, and when to route elsewhere. Nothing needed to call it 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?

With a single parameter and 100% schema coverage, the schema fully documents course_id (PLATO/Moodle numeric id from list_courses). The description adds no parameter-level meaning beyond this, so baseline 3 is appropriate.

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: retrieving completion status for every activity/module in a course. It clearly distinguishes itself from get_course_contents by noting it returns richer tracking rules. However, it never addresses the nearly identically named sibling get_course_completion_status, leaving a real ambiguity an agent could stumble on.

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?

Explicitly states when to prefer this tool (richer tracking rules like 'must view' vs 'must spend N minutes') and when to prefer a named alternative (get_course_contents for vod modules with watch-percentage and deadline info). Both the positive and negative routing conditions are stated.

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