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

With no annotations provided, the description must carry the behavioral burden. It discloses that this tool returns a flat list (as opposed to a nested tree) and that it optionally filters by module, which are important behavioral traits. However, it does not mention pagination, ordering, or error behavior. Still, for a simple list operation, this is reasonably transparent and exceeds the minimum.

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?

The description is exceptionally concise: two short sentences that front-load the action and include a valuable alternative pointer. Every word earns its place, with no redundancy or filler.

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 tool with only two parameters, no annotations, and no output schema, the description provides sufficient context. It tells the agent what the tool does, how to optionally restrict scope, and when to use a sibling tool instead. This covers the essential selection and invocation requirements for a list operation.

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 should compensate. It adds meaning to module_id by stating 'optionally filtered to one module,' which clarifies its role as a filter. However, course_id is only implicit from the tool name and required status, and no extra detail is given about parameter formats or relationships. This is modest compensation for the lack of schema description.

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 clearly states the tool's function: 'List lessons of a course, optionally filtered to one module.' It uses a specific verb ('List'), identifies the resource (lessons of a course), and clarifies scope (optionally filtered to one module). It also distinguishes itself from sibling tool hivelearn_get_course_structure by pointing out that the latter provides a nested tree.

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 description provides explicit usage guidance: 'Use hivelearn_get_course_structure for a nested tree' implicitly tells the agent to use this tool for flat lists. It also mentions the optional module filtering, clarifying when that parameter is relevant. This gives clear context for choosing between this and a key alternative.

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