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

Annotations already establish readOnlyHint=true, destructiveHint=false and openWorldHint=true, so safety is covered. The description adds genuinely useful context beyond that: results are returned in start order, cancelled classes are omitted unless include_cancelled is true, and an API key with app access is required. It does not describe pagination or result limits.

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?

It is short and front-loaded, leading with scope and return shape. There is mild redundancy between the first sentence ('with teacher, location, bookings and status') and the second sentence restating the same return fields, but nothing is padding.

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 return-value burden and does so reasonably: order, key fields, and cancellation filtering are all stated, and auth requirements are named. For a simple 4-param, zero-required read tool this is essentially complete.

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%, so the baseline is 3. The description goes beyond the schema by disclosing sort order (start order) and the default filtering behavior for include_cancelled ('hidden unless include_cancelled is true'), which the schema's terser parameter notes don't fully convey.

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 states a specific verb and resource ('Scheduled classes in a date range') plus the shape of each item (teacher, location, bookings, status), which is enough to distinguish it from momence_create_class, momence_cancel_class and momence_get_class_roster without opening any schema.

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 implies read/listing usage and adds downstream guidance ('Use class_id from each item in get_class_roster and the write tools'), which tells the agent what to do with results. However it never explicitly states when to choose this over sibling tools like create_class or cancel_class, so the usage guidance is inferred rather than stated.

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