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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds that it returns balance and tier info and that either a wallet address or email identifies the customer, which is useful, but says nothing about behavior for unknown customers, error cases, or whether results are live versus cached.

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 front-loaded sentence with the resource and return content before the parenthetical detail. The parenthetical is slightly clunky but nothing is wasted.

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 read-only, two-parameter tool with no output schema, the description adequately covers input shape and hints at the return content ('balance and tier info'). Only marginal gaps remain around error behavior and result freshness.

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 both parameters are documented in the schema, so the schema does the heavy lifting. The description restates the dual identifier option for customer_address but adds no semantics for token_address beyond what the schema already states.

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 verb and resource ('Get loyalty token balance and tier info for a customer'), which is clearly distinct from siblings like mint_loyalty_tokens or transfer_loyalty_tokens. It stops short of naming a sibling alternative, but the purpose 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 by the domain (a read lookup of a customer's balance), but there is no explicit when-to-use, no prerequisites, and no guidance on choosing between this and related tools such as list_loyalty_programs or get_my_profile.

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