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

Annotations declare read-only, non-destructive, idempotent, open-world. The description adds substantial behavioral context beyond that: page size (50), ordering ('newest first'), the cursor/limit paging pitfall (no next_cursor if limit is used), and a security warning that contract-provided names are untrusted. This is highly transparent.

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 front-loaded with the core purpose and result shape, then covers paging nuances and a security note. It is dense but every sentence earns its place; slightly verbose on the untrusted warning for a read-only listing.

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?

An agent has everything needed to invoke the tool correctly: what it returns, ordering, paging rules including the limit/cursor interaction, and the untrusted-data caveat. With no output schema and good annotation coverage, this description is complete.

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%, so the schema already documents limit, cursor, and address. The description adds semantic context for limit and cursor (paging behavior) but does not provide syntax or format beyond what the schema already gives. Baseline 3 is appropriate.

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 states a specific verb and resource ('A token's holders, largest first') and immediately enumerates the exact fields returned. It is clearly distinguishable from sibling tools like explorer_token_balances or explorer_address.

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?

It explains the crucial when-to-paging condition: 'leave limit out when paging through everything' and how to use the cursor. It does not name alternatives or say when not to use this tool versus the sibling token tools, but the context is clear for a paginated holder list.

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