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

Annotations already declare readOnly, idempotent, non-destructive, and openWorld, so safety is fully covered. The description adds one genuinely new behavioral fact—the $0.10 USDC charge—but discloses nothing about auth requirements, rate limits, or cost behavior on retries.

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?

A single dense sentence that front-loads the scope and lists the returnable signals plus cost. No filler, nothing repetitive.

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 an output schema present, return-value explanation is unnecessary, and the description correctly avoids duplicating it. For a two-boolean read tool whose annotations cover safety, the definition is nearly sufficient, lacking only explicit usage routing against sibling oracles.

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%, so both booleans (includeGasTrends, checkMerchantAccount) are already fully documented. The description adds no extra parameter meaning, which is the expected baseline when the schema does the work.

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 concrete purpose ('Pre-flight Arc Mainnet telemetry') and enumerates the exact signals returned (RPC latency, gas prices, USDC balance, account nonce). This clearly separates it from sibling oracles like arc_dex_oracle or arc_analytics, though 'telemetry' is a noun phrase rather than a crisp verb+resource.

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?

'Pre-flight' implies the usage context (a health/readiness check before acting), and the $0.10 USDC cost hints that it is a deliberate, occasional call. However, no alternatives or when-not conditions are named, so the agent must infer the timing itself.

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