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

The annotations already declare this as a read-only, non-destructive operation. The description adds behavioral context by explaining what the tool returns for different parameters, which is beyond the annotations. No contradiction with 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 two concise sentences, front-loaded with the core function, then optional behavior. No redundant information, perfectly efficient.

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?

Given the complexity of handling multiple token standards and optional params, the description provides adequate coverage of functionality. It doesn't describe the exact output format, but since no output schema exists, it partially compensates by listing what data is read. Minor gaps remain about error handling, but overall it is sufficient for a read 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?

The schema covers all parameters with descriptions, but the tool description adds semantics by explaining how holder and token_id affect the output (balance vs. NFT owner/URI). It also clarifies the network default, exceeding the schema's basic param descriptions.

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 reads token metadata (name, symbol, decimals, total supply) and optionally balance or NFT owner/URI. It uses specific verbs ('read', 'identify') and a clear resource (token), distinguishing it from siblings like account_info or call_contract.

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 explains when to use the optional parameters (holder for balance, token_id for NFT details), giving clear context for usage. However, it does not explicitly compare to alternatives or state when not to use, so it lacks exclusions.

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