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

Annotations already declare destructiveHint=true, readOnlyHint=false and idempotentHint=false, but the description adds the crucial side effect that sent/resent can fire the reward delivery email to the subscriber. It also surfaces the confirm gate, though it doesn't state whether a prior send can be cleanly undone.

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 the WRITE marker, followed by effects, then prerequisites, then the endpoint. No filler.

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 destructive mutation with full annotations and no output schema, the description covers side effects, the confirm requirement and id sourcing. Only failure behavior or reversibility of a send is left unstated.

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 baseline is 3; the description earns above that by explaining where reward_id must come from and framing status as the mutation target. It doesn't add format detail beyond the schema, which already documents uuid, status enum and confirm.

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?

Opens with a explicit write verb, the resource (an unlocked reward's status), and the exact allowed values (sent, resent, canceled). This clearly separates it from siblings like referralhero_unlock_promoted_reward or the list_* tools that only read rewards.

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 tells the agent the prerequisite for reward_id by naming two source tools (referralhero_list_subscriber_rewards, referralhero_list_unlocked_rewards) and explains the practical difference between the sent/resent and canceled paths. It stops short of an explicit 'do not use this when...' exclusion.

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