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

Despite having annotations (readOnlyHint=false, destructiveHint=true), the description adds critical context: it never signs, submits, or broadcasts, never moves funds, and never accepts private keys. This goes beyond what annotations indicate, clarifying the safe nature despite the destructive hint, and is especially valuable for a transaction-building tool.

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 sentences: front-loaded with the core purpose and source, followed by safety disclaimers and usage guidance. Every sentence earns its place with zero waste, making it concise and well-structured.

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 complexity (mutation, destructive hint, output schema present) and rich schema coverage, the description is quite complete—it covers purpose, usage, safety, and routing to sibling tools. It could be a 5, but the body parameter relies on get-endpoint for details, which slightly reduces completeness.

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 provides detailed descriptions for both parameters (path enum with descriptions, body with reference to get-endpoint for exact schema). The description does not add extra parameter semantics beyond pointing to get-endpoint for the body schema, so a baseline of 3 is appropriate given 100% schema coverage.

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 verb 'builds an unsigned Solana transaction' and the resource (Vybe Solana API), and lists the three specific operations it supports (swap, close-token-accounts, withdraw-mev), which distinguishes it from query-vybe-api and other siblings. This is specific and unambiguous.

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 provides explicit guidance on when to use this tool vs alternatives: 'Use query-vybe-api with /v4/trading/swap-quote first when the user only wants a price quote.' This explicitly names the sibling and the condition that selects it, which is excellent.

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