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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, openWorldHint, destructiveHint=false), and the description adds genuinely new behavior beyond them: schedules are explicitly unavailable when not published, listed classes do not guarantee remaining seats, and output is English natural-language text with sources, conditions and pagination preserved. These are exactly the partial-result and caveat traits an agent needs.

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 action in the first clause and no filler sentences; the caveats are compressed into short statements. The final sentence about English text, sources and pagination is slightly dense relative to its value, keeping it out of the top band.

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 no output schema, the description usefully sketches what comes back (dates, fees, provider/campus details, pagination) and what does not (unavailable schedules), so an agent knows what to expect. The claim that the endpoint 'returns English natural-language text' sits awkwardly beside a locale enum defaulting to zh-CN, leaving a small ambiguity about result language.

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 both seoId and locale are already documented, including the enum values and URL language-prefix effect. The description only reinforces that seoId must be exact, which the schema already states, and says nothing new about locale; 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 ('Get a published short course by exact seoId'), names the lookup key, and scopes the result (public provider/campus details, class dates, fees). An agent can distinguish it from sibling search_short_courses purely from the text.

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 'exact seoId' phrasing plus the schema note that seoId comes from search_short_courses implies this is a follow-up detail lookup rather than a search, and 'Read-only: use returned website links to apply' tells the agent what to do next instead of attempting a write. No explicit when-not or named alternative appears in the description itself, so it falls short of a 5.

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