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

Annotations already mark read-only/non-destructive, and the description adds substantial behavioral context: the reference price source and fallback, the flat-gas-cost assumption, the returned metrics, and the USDC payment. No contradiction with 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?

Three sentences are tightly packed: use case, output, exclusions, and cost. Front-loaded with the most important instruction; no filler.

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 read-only analysis tool with full schema coverage and an output schema, the description provides all necessary selection and invocation context, including payment and scope. It even disambiguates against sibling tools.

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?

Input schema covers all 6 params with descriptions (100% coverage), so baseline 3 applies. The description adds context about the analysis (gross/net spreads, assumed gas) but does not add parameter-level detail beyond the schema.

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 use case (pre-trade arbitrage check), defines the exact comparison (global reference price vs DEX pool price), and explicitly excludes unrelated uses (liquidity depth, contract security), which differentiates it from sibling tools.

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?

Explicitly says when to use ('before executing a cross-venue arbitrage trade') and when not to use ('Do not use for DEX-only liquidity depth checks or contract security'), pointing to alternative categories among siblings. It also mentions the cost and network context.

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