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

Annotations already declare readOnly/idempotent/non-destructive, and the description adds value beyond them: it states the call is paid per-invocation, specifies the amount and currency (USDC or prepaid credits), and tells the agent payment must ride in MCP request headers (X-Payment / X-Payment-Tx / Authorization: Bearer fg_…) rather than in arguments. It does not say what happens when payment is missing or invalid, so it stops short of 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 Chinese-English full duplication nearly doubles length without adding information, and the pricing is restated twice with contradictory figures ($0.005 in the header line vs $0.07 USDC in the body). The front-loaded question is well placed, but the rest of the block repeats rather than extends.

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 one-parameter read-only status call with strong annotations and no output schema, the description covers domain, cost, and payment mechanics, which is most of what an agent needs. It omits failure/error behavior and exchange-value format, and the duplicated inconsistent price undermines confidence.

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 0% for the single 'exchange' parameter (nullable, default null, no title help). The description partially compensates by enumerating the covered venues (OKX/Binance/KuCoin/Bybit/Gate), which defines the parameter's domain, but it never states the accepted value format (ticker vs id, casing) or what a null default returns.

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 opening question 'are the exchanges up right now' plus the enumerated outputs (per-exchange latency, maintenance titles, server clock skew) gives a concrete verb+resource picture an agent can act on. It does not name or distinguish itself from the sibling exchange-status.overview, leaving overlap ambiguous.

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 framing implies the usage context (checking live exchange availability/maintenance) but gives no explicit when-to-use vs when-not, and never routes to exchange-status.overview or the listing-intel siblings. The '$0.005' vs '$0.07' price conflict further muddies the cost decision the agent is being asked to make.

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