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

Annotations already declare readOnly, idempotent, open-world, non-destructive, so the safety profile is covered. The description adds genuinely non-obvious behavior: it is a paid call at $0.03 USDC or prepaid credits, and payment credentials must travel in MCP headers (X-Payment / X-Payment-Tx / Authorization: Bearer fg_…), not in parameters. It stops short of describing failure modes or what happens on unpaid calls, which keeps it from 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?

The core statement is front-loaded, but the same content is then repeated in a bilingual block — the field list appears twice and the paid-vendor/args/payment information is duplicated in [zh] and [en]. The duplicated payload is not concision, and the full-width pipe separator adds noise.

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, listing the returned fields is a real contribution, and the payment/auth mechanics are spelled out, which is the main risk an agent faces here. What is missing is parameter semantics for all three arguments, which is the largest remaining gap for a tool this simple.

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 0% and the three parameters are only restated by name ('Args: limit, chain, source') with no added meaning. There is no indication of accepted chain values, what 'source' selects, or how limit interacts with a 'full' board, so the description fails to compensate for the empty 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?

The description names the resource concretely — the '新币热度榜 (DexScreener 推广位)' / token heat board — and frames it as 'what tokens are being promoted right now' with a full field list (symbol, chain, address, promo spend, price, liquidity, FDV). That is a specific verb-plus-resource statement an agent can act on. It does not, however, contrast itself with the sibling token-heat.heat_now, so it never states whether this is the full version of that tool.

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?

Usage is only implied: the word 'full' hints this is the comprehensive variant, but no alternative is named and no condition for choosing it over heat_now is given. There is no statement of when not to call it, though the cost disclosure implicitly discourages casual use.

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