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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered; the description adds genuinely new behavioral context: the accepted credential types, that it is read-only, and that paired access is limited to your own human. It stops short of describing pagination or return shape.

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 dense sentences with the resource and contents front-loaded; the telegraphic 'Unpaired: your own; paired: your human's' phrasing is efficient and readable. Nothing is wasted, though the parenthetical credential clause is slightly compressed.

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 does carry the burden of indicating what comes back, and it enumerates the progress categories. Auth requirements and pairing scope are also covered. Only the distinction from the similar get_progress sibling is missing.

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 100% and the single token parameter is fully documented in the schema, including its fallback role and preference order versus the Authorization header. The description references token/key credentials but adds no syntax or format detail beyond the schema, 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?

States a specific resource (saved learning progress) and enumerates its contents: completed lessons, quiz results, mastered lessons, learning points. It also scopes the result by pairing state (unpaired = your own, paired = your human's). It does not, however, differentiate itself from the sibling get_progress, which an agent would likely confuse with this tool.

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 gives auth context (agent_signup token or paired agent key from pair_agent) and a scope restriction (read-only, your own human only), which implies when the tool is applicable. But it never states when to call this versus get_progress or other progress-related siblings, leaving the selection decision to inference.

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