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

Annotations already cover the read-only/idempotent/non-destructive profile, so the bar is lower, and the description still adds real value: it discloses the exact data source (mainnet mirror node logs), the two possible result shapes, and a trust property ('never a fabricated receipt'). It stops short of noting latency, caching, or failure behavior when the mirror node is unreachable.

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 front-loaded sentences plus 'Read-only.' at the end; the source scan and return contract come before the redundant tail. The trailing 'Read-only.' largely duplicates readOnlyHint, a minor wasted clause, but overall the text is tight.

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?

There is no output schema, so the description has to carry return-value disclosure, and it does: verified=true with listing title and transaction id, or verified=false. Combined with the named contract and network, an agent has everything needed to call and interpret this tool.

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 description coverage is 100%, so wallet and listing_ref are already documented in the schema; the description's mention of 'the wallet as buyer' and 'the listing ref' restates rather than extends that. Baseline 3 applies since the schema does the heavy lifting.

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 (verify) and a specific resource (a wallet's marketplace purchase), then names the exact mechanism: Voicescape Tips contract 0.0.10854060 PurchaseCompleted logs on the Hedera mainnet mirror node. This is clearly separable from sibling tools like verify_tip and my_purchases without opening either schema.

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?

The description makes the verification context clear ('for the wallet as buyer and the listing ref') but never states when an agent should call this instead of a sibling such as my_purchases or verify_tip, nor any prerequisites or exclusions. Usage is implied by the resource it operates on rather than stated.

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