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

Annotations already cover read-only, idempotent and non-destructive semantics, and the description goes meaningfully beyond them by disclosing a daily per-caller quota, the exact return composition (listed / unlisted / unreachable exchange lists), and the critical operational detail that X-Payment / X-Payment-Tx / Authorization headers must travel in HTTP headers rather than parameters. What it does not say is what happens when the quota is exhausted or what an unreachable exchange means for result completeness.

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 sentence is well front-loaded, but the definition then restates the same facts in Chinese, then again bilingually with vendor boilerplate ('供应方资产「五所上币与最小下单量」... Args: symbol, quote'), roughly tripling length for no added information. The payment-header warning, which is the most operationally important sentence, is buried last.

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?

For a two-parameter read with no output schema, the description covers purpose, return fields, cost model and auth placement adequately. The remaining gap is input format for symbol and quote, which matters given the tool routes on those values.

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%, so the description carries the full burden; it does state that symbol is required and quote is optional, but it only repeats the schema's own required/default structure. It adds one useful fact (quote is the quote currency, USDT by default — which slightly conflicts with the schema's null default) but gives no symbol format guidance (e.g. 'BTC' vs 'BTCUSDT'), which is the single most likely invocation error.

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 question the tool answers ('which exchanges list this coin') and quantifies the scope (5 exchanges), then enumerates the four returned lists. It is immediately clear what the tool does, but it never distinguishes itself from near-neighbours like listing-status.listing_detail or exchange-listing-intel.exchange_matrix_entry, so an agent must guess which is the aggregate check versus the detail drill-down.

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?

The phrasing 'Ask "which exchanges list this coin"' implies the triggering user intent and notes the free tier, which is helpful context. However there is no explicit statement of when NOT to use it, no pointer to the detail/matrix siblings, and no guidance on the relationship between a free quota-exhausted call and a paid one.

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