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

Annotations already flag destructiveHint=true and openWorldHint=true, and the description adds real value: a read-back-and-confirm protocol gated on confirmation=true, the irreversibility that a paid class cannot be cancelled, and an account-ownership prerequisite. However it does not say what happens to attendee bookings if a cancel is attempted despite the rule, or whether edits to a booked class are silently restricted to certain fields.

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?

Front-loaded with the usage trigger, then proceeds through action semantics, confirmation protocol, constraints and auth requirement, with no filler sentences. It is somewhat run-on, packing multiple rules per sentence, but every clause carries operational information.

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?

For a 10-parameter mutation tool with destructive semantics, the description covers the confirmation gate, irreversibility caveats and account prerequisite, and an output schema exists so return values need not be described. Remaining gaps are edge behavior: which fields are editable on a booked class and what error a non-owner or unpaid-account caller receives.

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 80%, so the schema documents most parameters; the description adds meaning mainly for confirmation (must be true only after the owner said yes) and action=list being non-mutating. Editing restrictions implied by 'a class people booked keeps its time, length and price' are not mapped to specific fields, leaving which of title/minutes/capacity/starts_at are locked ambiguous.

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 (class schedule) with a clear verb set (see, add, change, cancel) and scopes it to owners editing their own place, which separates it from book_gym_class and find_gym_class. It never names a sibling explicitly, so differentiation is inferred from the owner framing rather than stated.

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?

Opens with an explicit when-to-use trigger ('when an owner wants to...'), explains that action=list is a pure read, and gives the positive/negative conditions: a booked class keeps its time/length/price, and a class members paid for cannot be cancelled here. Payment is redirected away from this tool to Phorme's own payment page.

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