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

Annotations already cover read-only and open-world behavior, so the bar is lower; the description adds the concrete cost model ($0.005 USDC per call via x402) and the payment endpoint, which is material for deciding whether to call it. It does not state whether results are cached or how staleness is handled.

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?

A single front-loaded sentence states what is returned, followed by a compact pricing note. The raw URL is slightly noisy but earns its place as the payment endpoint.

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 only two parameters, full schema coverage and no output schema, the description covers the essential behavior and enumerates the returned fields well enough for an agent to know what it will get back. Missing only edge-case behavior for invalid or non-existent mints.

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%, with the mint address format and the payment header semantics already documented in the schema. The description adds nothing about either parameter, so the baseline 3 applies.

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 names the resource (SPL token mint) and the exact data returned: total supply, decimals, mint authority and freeze authority. That distinguishes it well from balance-oriented siblings such as solana_token_balances and safety-oriented solana_token_safety, though it never names an alternative explicitly.

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?

Usage is implied by the returned fields (metadata/authority lookup rather than holder or balance data), but there is no explicit when-to-use or when-not-to-use guidance, nor any mention of the sibling tools an agent might confuse this with.

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