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

Annotations already provide readOnlyHint, idempotentHint, and destructiveHint=false, establishing the tool as safe and read-only. The description adds context about using the configured Solana RPC endpoint, routing instructions, and the signer boundary (no keypair bytes), which goes beyond annotations. However, it lacks details on potential rate limits or response size.

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 contains two sentences of functional description followed by a lengthy block of 'SAP MCP execution guidance' that is repetitive (appears again in the schema description). This bloat reduces conciseness; the core purpose could be conveyed in one sentence without the boilerplate.

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 tool's simplicity (read-only, one resource), the annotations, and the presence of an output schema (indicated by context), the description adequately covers the tool's behavior and constraints. The execution guidance adds useful context for the agent's decision-making.

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 input schema has 100% description coverage, so each parameter (pubkey, address, commitment) is adequately documented in the schema. The description adds no extra semantic information about these parameters beyond the schema, so it meets the baseline but does not exceed expectations.

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 it fetches the SOL balance for a wallet or account, using a specific verb ('Fetch') and resource ('SOL balance'). It distinguishes itself from sibling tools like spl-token_getBalance by focusing on native SOL rather than SPL tokens.

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 includes SAP MCP execution guidance that frames the tool as a read/discovery workflow with free pricing, which helps the agent decide when to use it. However, it does not explicitly compare to sibling tools or state when not to use it, leaving some ambiguity.

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