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

Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=false, so the safety profile is covered. The description adds only a scope boundary (no medical/crisis use), not behavioral detail such as whether history is scoped to the current month, what happens without a tap token, or how missing data is reported. With annotations carrying the safety burden, this is adequate but thin.

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 with the positive trigger front-loaded and the exclusions after it. Nothing is padded, though the two negative sentences could be compressed into one without losing meaning.

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?

All parameters are optional and fully documented in the schema, there is no output schema to explain, and annotations cover the read-only profile, so the description only needs to establish purpose and scope, which it does. The one gap is that it never tells an agent how this differs from the progress/history siblings when a user asks an ambiguous listening-stats question.

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%: both `tap` and `timezone` are documented in the schema, including the pointer to keep_progress and the IANA format. The description adds no meaning beyond that, so the baseline of 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 concrete resources returned: badges, days listened this month, and what the user has earned. It is not a bare verb+resource statement (it is phrased as a usage trigger), and it does not distinguish itself from nearby siblings such as my_progress or my_history, but the data domain is specific enough that an agent can tell what it retrieves.

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?

It gives explicit when-to-use conditions (badges, days listened this month, earned rewards) and explicit exclusions (medical questions, emergencies, crisis, general meditation chat). It stops short of the top score because it never routes to a sibling for the adjacent cases it excludes, so an agent must guess where a general progress question goes.

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