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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds useful behavioral context beyond that: the rubric has a descriptor for every level and the tool links to a page with a CSV download, telling the agent what it is really receiving.

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, front-loaded with what the rubric is, then its contents, then the download link and the sibling contrast. Every sentence carries information; nothing is padded.

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 parameters, an output schema present, and read-only annotations, the description does the semantic work of locating this rubric relative to the analysis tools' own rubric. It is complete for invocation, though it could note whether the returned link/CSV is the primary deliverable.

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 are zero parameters, so there is no parameter meaning to add; the baseline of 4 applies. The description correctly refrains from inventing argument semantics.

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?

Names a specific resource (a four-level speaking rubric) and enumerates the exact dimensions it covers (fluency, pronunciation, vocabulary range, task completion), so the agent knows precisely what it will get. It also explicitly distinguishes this rubric from the scoring rubric used by analyze_transcript and analyze_speech.

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 frames this as the teacher-facing homework rubric and contrasts it with the 1-10 scoring rubric used by the analyze_* siblings, which steers selection correctly. It stops short of an explicit 'use this when…' rule, so it falls just below full routing guidance.

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