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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, indicating a safe, repeatable read operation. The description adds no further behavioral context such as pagination behavior, multi-chain support, or the meaning of openWorldHint. It is essentially a restatement of the title.

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?

The description is extremely brief and avoids redundancy, but it is under-specified rather than productively concise. A single noun phrase conveys the core idea but lacks the structure of a full sentence like 'Gets the list of NFTs owned by a wallet address.'

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 5 parameters and an output schema, the description is starkly minimal. It gives no guidance on pagination, filtering, chain behavior, or when to use this tool. The output schema covers return values, but the contextual usage and parameter semantics are largely missing.

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 0%, so the description needed to explain parameters. It only hints that 'owner' is an address via the phrase 'by address,' but does not explain 'contracts', 'chain', 'page_key', or 'page_size'. The examples in the schema provide some clues, but the description itself does not compensate.

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 'NFTs owned by address' clearly identifies the resource (NFTs) and scope (by wallet address), distinguishing it from siblings like nft_owners (reverse lookup) and nfts_for_collection. However, it lacks an explicit verb such as 'Gets', so it is not a fully specified purpose.

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 provides no guidance on when to use this tool versus alternatives. It does not mention that this tool is for looking up NFTs held by a wallet, nor does it reference related tools like nft_owners or nfts_for_collection. No exclusions or alternative use cases are indicated.

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