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

Beyond the readOnlyHint and destructiveHint annotations, the description adds valuable behavioral detail: it never signs, spends, or touches a mandate, requires Authorization: Bearer <JWT>, and covers both Token and Token-2022 programs. This goes well beyond what annotations alone convey and contains no contradiction.

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 three tight sentences: the core function comes first, the default no-argument behavior second, and the safety/auth requirements last. Every sentence earns its place with no filler or redundancy.

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 simple one-optional-parameter read-only tool, the description covers purpose, default behavior, authentication, and side-effect safety. The absence of an output schema means an explicit return-shape description would be helpful, but the tool's function is simple enough that the current text is nearly 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%: the only parameter, address, is already described as 'A Solana address to inspect. Omit to report your own Signet session addresses. Balances are public data.' The tool description mostly restates this default behavior rather than adding new parameter-level semantics, so the schema carries the weight and a 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 action and resource: it reports live on-chain balances of native SOL and SPL holdings for an address. It clearly distinguishes itself from the other signet_* siblings by emphasizing it is read-only and never signs, spends, or touches a mandate. The default no-argument behavior is also explicitly described.

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 gives clear context: omit the address to see your own Signet session addresses, pass an address to inspect it, and expect public data. It does not explicitly name alternative tools or say 'use this instead of X', but the read-only framing and safety note imply when this tool is appropriate versus mutation-oriented siblings.

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