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

Goes well beyond the readOnly/openWorld annotations by disclosing the cost model ($0.002 USDC per call), the payment rail (x402, USDC on Base/Solana/Polygon/Arbitrum), which clients pay automatically, and the cursor-based stateful behavior across calls. This is exactly the auth/pricing/rate context an agent needs and cannot get from 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 purpose, return fields, then workflow and pricing, with no wasted sentences. The inline sample-input JSON is long but earns its place by showing a free-call path; slightly heavy overall.

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 fully enumerates the return payload (direction, amount, status, time, explorer link, balance) plus the cursor contract and payment requirement. An agent has everything needed to call and continue the watch loop correctly.

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 coverage is 100%, so the baseline is 3, but the description adds real meaning: it explains cursor provenance ('first call returns recent transactions and a cursor; pass the cursor back') and demonstrates limit usage in the sample input. It does not restate the 1-50 range, which the schema already covers.

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 (watch), resource (IOTA mainnet address or IOTA name), and enumerates exactly what is returned: direction, amount, status, time, explorer link, balance. This distinguishes it from siblings like iota_address, iota_tx, and iota_verify without opening any 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?

Names concrete scenarios (deposit detection, treasury and whale watching) and explains the polling workflow: first call returns a cursor, pass it back for only new transactions. It does not explicitly contrast with alternatives such as iota_tx for a one-off lookup, so it stops short of the top score.

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