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

Annotations already declare readOnlyHint=true and openWorldHint=true, but the description adds substantial non-annotation context: a per-call price of $0.002 USDC settled via x402 on Base/Solana/Arc and the fact that failures are not charged. It does not cover rate limits or pagination/ordering guarantees beyond "newest", keeping it below a 5.

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 compact clauses, front-loaded with the resource and scope, then exclusions, then cost. Each sentence earns its place; the only slight density is the payment-mechanism detail, which is nonetheless decision-relevant.

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, the description needn't explain return values, and it already covers scope, exclusions, the limit range and the cost/auth model. What it omits — freshness/update cadence of "newest" and any rate limits — is minor for a read-only public-API lookup.

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% for the single `limit` parameter, so the schema already carries the range and default. The description only adds the ordering semantics ("newest N"), which is a modest increment, so the baseline 3 for a fully documented schema is appropriate.

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 names a specific verb and resource (newest N jetton masters from TON Center's public API) and enumerates the returned fields (raw address, total supply, mintable flag, admin address, metadata URI). This clearly distinguishes it from siblings like crypto_solana_token_extensions or crypto_token_holder_concentration, which cover other chains or holder-level data.

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 carves out scope explicitly ("Jetton holder balances and Toncoin staking are not included"), steering the agent away from misuse, and the pricing note tells the caller when a call is cost-bearing. It stops short of naming a specific alternative sibling to use for holder balances or staking, so it is clear context rather than full routing guidance.

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