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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered; the description adds genuinely non-derivable behavior in the metered pricing model ($0.005 USDC per call, x402 on Base), which materially affects invocation. It does not state data freshness/latency or whether an unknown symbol errors or returns empty.

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?

Two sentences plus a pricing clause, with the core resource scoping front-loaded and the prerequisite usage condition second. No filler, and each clause carries distinct information (what, when, cost).

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 compensates by enumerating the result fields (flags, delisting date, suspended networks), and it adds the cost and usage trigger. An agent has everything needed to decide to call it and to send a plausible symbol.

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% for the single required parameter, and the description only implies it is a coin ("for one coin"), adding no format guidance such as whether to pass "BTC" or "KRW-BTC". It gives marginal meaning beyond the bare schema but leaves the identifier convention unresolved.

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?

Names a specific resource (Korean exchange risk status for one coin), scopes it to two named venues (Upbit and Bithumb), and enumerates the returned data classes (warning/caution flags, pending delisting with date, suspended networks). This is clearly distinguishable from nearby siblings like kr_crypto_events without opening either 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?

"Check before trading or routing a transfer to a Korean exchange" gives an explicit triggering condition and the decision it informs. No alternative sibling (e.g. kr_crypto_events) is named or excluded, so it stops short of a full when/when-not routing statement.

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