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

Annotations already declare this is a read-only, non-idempotent operation, so the safety profile is covered. The description adds genuine value by disclosing the return structure (per-validator rewards plus a total), but says nothing about auth requirements, pagination, or why the result is non-idempotent (rewards accrue over time).

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?

Two short sentences, front-loaded with purpose and followed by the concrete return content. No filler, no redundancy.

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 usefully compensates by summarizing the response shape (per-validator and total rewards). For a simple single-parameter read tool this is nearly complete; only guidance on downstream usage or edge cases (e.g. no delegations) is absent.

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 the single parameter already carries its own description ('Delegator address (thor1...)'), including the address format. The description only restates the delegator concept, adding no syntax or format detail beyond the schema, so 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 gives a specific verb+resource: 'Returns delegation rewards for a delegator address,' and the second sentence clarifies the content (per-validator plus total). It is clearly distinct from siblings like get_cosmos_delegations or get_cosmos_balances, though it never names a sibling to reinforce the boundary.

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?

There is no when-to-use guidance, no prerequisites (e.g. the delegator must have an existing delegation), and no mention of alternatives such as get_cosmos_delegations. Usage is only implied by the single-parameter signature.

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