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

Adds context the annotations cannot express: pricing (0.05 USDC per call via x402, with the accepted settlement chains), and failure semantics ('503 if it cannot simulate: not charged') so the agent knows a retry costs nothing. The readOnly/idempotent hints are already covered, but the cost and failure contract are genuinely new information.

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, front-loaded with the usage trigger, then the return payload, then the cost/error contract. Every sentence carries information an agent needs and there is 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?

Returns are covered by an output schema, and the description still summarizes what comes back; chain scope, payment model, and failure behavior are all stated. Nothing essential for correct invocation is missing.

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 each parameter already documents its chain-scoped meaning (to/data/from/value for base, tx for solana). The description adds no parameter-level detail such as base64 vs hex requirements, so the schema does all the work — baseline 3.

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?

Names a specific verb and resource ('see what a Solana or Base transaction does before signing it') plus the concrete return payload (simulated balance changes, approvals, new accounts, warnings). An agent can distinguish this from token-level siblings like get_token_risk or get_honeypot_check without opening a schema.

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?

'Use when an agent needs to see what a ... transaction does before signing it' gives a clear triggering condition and implies the pre-signing step in a workflow. It does not name an alternative tool or state when not to use it, which keeps it below a 5.

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