List courses

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

Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is covered. The description adds two genuinely useful behavioral facts beyond that: results are sorted by title and each row carries ordered item ids. It says nothing about pagination, result size, or what happens when no band/subject is supplied.

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 sentences with no obvious padding, and the return-shape fact is front-loaded. But the middle sentence is dense domain jargon ('a subject unit's sittings') that costs more reading than it repays, and the ordering detail is split awkwardly from the row-content detail.

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 does useful work by stating the sort order and that rows contain ordered item ids. For a two-parameter filtered list tool, though, the absence of any filter semantics, optionality, or pagination behavior leaves real gaps for correct invocation.

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% for both parameters, so the description must compensate and largely does not. The phrase 'for one band' hints at the band parameter but never explains what a band is, and the subject parameter is not referenced at all; it is also unstated that both filters are optional and that omitting them returns the full catalog.

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 defines the domain concept ('A course is a book or a subject unit's sittings for one band') and says rows include ordered item ids, so the agent can infer it returns course listings in title order. However, it never states the action plainly ('lists all courses') and the opening phrase 'Books and lesson tracks in title order' is ambiguous about whether books and lesson tracks are the returned entities or something else. It does not differentiate itself from siblings like get_course_outline or list_by_age_band.

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?

There is no when-to-use guidance and no mention of alternatives, despite siblings such as get_course_outline, list_by_age_band, search_content, and get_catalog_info that plausibly overlap. The agent is left to guess whether this is the browse-everything call or a filtered one.

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