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

Annotations already declare readOnlyHint/openWorldHint/destructiveHint, and the description adds meaningful behavior beyond them: it discloses the routing mechanism (Jupiter aggregator, all known pools) and the failure mode ('routable (false + error if the size can't be routed at all)'). That failure disclosure is genuinely useful and not in the annotations.

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?

Front-loaded with the core mechanic, then usage triggers, then the return list. The return enumeration is somewhat dense but earns its place since there is no output schema. No filler sentences.

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 usefully enumerates the return fields and the routable failure case, and annotations cover the safety profile. It is complete for calling the tool correctly, though it omits any note on response timing/refresh ('live') or rate limits.

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 100% and all three parameters are documented there, including the human-units caveat and the outputAsset default. The description adds nothing parameter-specific, so the baseline 3 is correct.

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 gives a specific verb+resource ('live price-impact quote for a Solana token swap') and immediately distinguishes its method from rivals: routed through Jupiter across every pool, 'not a single-pool estimate' — which separates it from siblings like run_orderbook_impact and run_impermanent_loss.

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?

It gives two concrete user-question triggers ('how much slippage will I eat...', 'what will I actually get if I sell N tokens?'), making the use case clear. It does not name an alternative tool or state when NOT to use it, so it stops short of full routing guidance.

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