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

No annotations exist, so the description carries the full burden; it does add value by disclosing the return shape (subjects plus lesson URLs), which is otherwise undocumented since there is no output schema. It says nothing about matching behavior, result limits, ordering, or whether the library requires auth, leaving meaningful behavioral gaps.

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 short sentences with zero filler, and the core action is front-loaded ahead of the return-value note. The brevity is efficient, though it comes at the cost of the missing detail scored elsewhere.

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 one parameter, no annotations, and no output schema, the description covers the essentials of what it does and roughly what comes back. It is still incomplete on query semantics and result behavior, which an agent needs to call it effectively.

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?

There is one required parameter with 0% schema description coverage, so the description must explain it and does not. It never says whether 'query' matches subject names, lesson content, or free-text keywords, nor whether partial or exact terms work.

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 gives a concrete verb and resource: 'Search the Teach Me learning library' returning 'subjects with their lesson URLs.' That is enough to distinguish it from get_course and get_lesson, which are clearly single-item retrievals. It stops short of naming those siblings, so a 5 is not warranted.

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 — an agent can infer 'use this to find subjects' from the verb 'Search,' and the contrast with get_* tools is left implicit. There is no statement of when not to use it, no prerequisite, and no mention of what to do with the returned lesson URLs.

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