Lesson details

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

readOnlyHint=true and openWorldHint=true already establish the safe-read, external-network profile, so the description adds only the return-content inventory. It says nothing about auth requirements, failure modes for an invalid lesson number, or whether fields like self-test are always present. No contradiction with the annotations.

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?

One front-loaded sentence, with the core purpose first and field details after. The trailing clause 'watchUrl, the link to watch it on the platform' is slightly wordier than necessary but still earns its place.

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?

There is no output schema, so enumerating the returned fields (objectives, teacher, paragraphs with duration/progress, handout URL, self-test, watchUrl) does real work. With only two schema-documented parameters, the definition covers what an agent needs in order to call and interpret the result.

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 coverage is 100% and both parameters are documented, including that the course code comes from list_courses and the lesson number matches list_lessons. The description adds no further parameter meaning, so the 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?

A specific verb-plus-resource ('Full details of one lesson') that is clearly the detail counterpart to list_lessons, and it enumerates what the payload contains. It never explicitly names the sibling, so the distinction is inferred rather than stated.

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?

Usage is only implied: fetch a single lesson's details rather than a listing. There is no explicit when-to-use, no named alternative, and no preconditions such as needing a course from list_courses first.

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