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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the safety profile is covered. The description adds value beyond that by disclosing the aggregate content the call assembles (plan plus named materials plus links), which tells the agent this is a fan-out read rather than a single-record fetch. It does not discuss missing links or partial results, so it is not fully transparent.

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?

Two sentences, no filler, with the returned content stated first and the follow-up action second. The first sentence is a dense comma-separated inventory but each item is informative rather than redundant.

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 carries the burden of describing the return value, and the enumeration does that reasonably well. The gap is that it tells the agent to 'pass its set item' without explaining what a set item is or where it appears in the response, leaving a required handoff underspecified.

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 the schema already explains the grade forms accepted (pk, k, 1-5, 'kindergarten', '3rd grade') and the dotted lesson number format. The description adds no parameter meaning of its own, 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?

The description names the resource (one curriculum lesson) and enumerates the payload precisely: goal, lesson plan page, worksheets, maker settings, tool, quiz, exit ticket, each with a link. That is far more specific than a restatement of the name and lets an agent distinguish it from a plain curriculum listing. It stops short of a clean verb+resource opener, but the scope is unmistakable.

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 second sentence gives one concrete downstream flow — pass the set item to make_set_link to give a teacher the whole lesson in one link — which implicitly frames when this tool is the right entry point. There is no explicit statement of when to use get_lesson versus get_curriculum, nor any exclusion or prerequisite.

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