nft_tokens_by_address

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

The description adds valuable behavioral context beyond what annotations provide. While annotations declare readOnlyHint=true and destructiveHint=false, the description specifies that results are 'grouped by collection' and provides details about the response structure (collection details and individual token instance data). Most importantly, it explicitly documents pagination behavior with specific instructions about the 'pagination' field and 'next_call', which is critical operational knowledge not captured in annotations.

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 efficiently structured with three focused sentences and a bold pagination note. The first sentence states the core functionality, the second details the response structure, the third provides usage context, and the pagination note delivers critical operational guidance. Every sentence earns its place with no redundant information.

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 tool with good annotations but no output schema, the description provides excellent context about what the tool returns (collection details and token instance data) and critical pagination behavior. It could potentially benefit from mentioning response format specifics or error conditions, but given the annotations cover safety aspects and the description explains the response structure well, it's quite complete for agent use.

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?

With 100% schema description coverage, the input schema already fully documents all three parameters (chain_id, address, cursor). The description doesn't add any parameter-specific information beyond what's in the schema, but the baseline of 3 is appropriate when the schema provides complete parameter documentation.

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 clearly states the tool's purpose with specific verbs ('retrieve NFT tokens owned by an address') and resources (ERC-721, ERC-404, ERC-1155 tokens). It distinguishes from sibling tools like 'get_tokens_by_address' by specifying NFT tokens grouped by collection rather than general tokens, and from 'get_address_info' by focusing on NFT holdings specifically.

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 clear context for when to use this tool: for getting a detailed overview of an address's digital collectibles with collection data. It doesn't explicitly state when NOT to use it or name specific alternatives, but the context is sufficiently clear for an agent to understand this is for NFT holdings analysis rather than general token balances or address metadata.

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