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

Annotations already declare readOnlyHint=true, destructiveHint=false and openWorldHint=true, so the safety profile is covered; the description's 'Read-only' is largely redundant. It does add genuinely new behavioral context: the native-coin address must come from list_chains, and Solana mints are case-sensitive base58. It says nothing about rate limits, quote expiry, or freshness.

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?

Three short sentences, front-loaded with the core action and the non-committal guarantee, then the chain-specific caveats. No filler or repetition.

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 no output schema, the description should indicate what a quote contains (rate, expected buy amount, route, fees, expiry), but it only says it prices a swap. Combined with the undocumented chainId and sellAmount parameters, an agent can call it but cannot anticipate the response shape.

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 description coverage is 0% across five parameters, so the description must compensate and only partly does: it explains buyChainId (cross-chain pricing), the sellToken/buyToken formats for native coins and Solana mints. chainId and sellAmount (a string matching ^\d{1,78}$, presumably base units) are left entirely unexplained.

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?

States a specific verb and resource ('Price a swap') and immediately scopes it as non-committal, which implicitly separates it from execute_swap and prepare_swap. It stops short of naming those siblings explicitly, so the differentiation is inferred rather than stated.

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?

Gives clear when-to-use context ('without committing to it') and adds chain-specific applicability: native coin via list_chains address, EVM cross-chain via buyChainId, Solana base58 mints. It does not explicitly say when to prefer prepare_swap or execute_swap instead, so the routing guidance is incomplete.

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