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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so safety needs no restating. The description adds genuine substance with no output schema present: it enumerates the returned fields (trigger type, fixed vs percent amount logic, payout type, delivery delay), letting the agent know what data it will get. It omits multiplicity/pagination and empty-result behavior, keeping it short of a 5.

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?

A single dense sentence front-loads the resource and then lists the returned fields, followed by the endpoint for orientation. Nothing is padded, though the field list is somewhat compressed and the parenthetical qualifiers add length without much disambiguation.

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 single-parameter, read-only list tool with no output schema, the description covers what the tool returns and what scopes it, while annotations cover the safety profile. Only minor gaps remain: whether multiple rules can be returned and how they are ordered.

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% and program_id is documented as a GUID with a cross-reference to referralrock_list_programs. The description reinforces scoping ('of one program') but adds no format or constraint 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?

The description names the resource precisely (reward rules of a program) and enumerates its content — trigger conditions, amount calculation, payout type, delivery delay — which separates it from sibling tools returning actual reward or payout records. It lacks an explicit verb like 'list'/'retrieve', so the read action is inferred from the noun phrase plus the endpoint, but the scope is unambiguous.

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?

Usage is implied: this is the per-program configuration lookup, referenced implicitly against siblings like referralrock_list_rewards and referralrock_list_pending_payouts, which return transactional data. However, no explicit when-to-use or when-not-to-use statement or named alternative is given, leaving the agent to infer the config-vs-transaction distinction.

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