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

Annotations already cover the safety profile (readOnlyHint=true, destructiveHint=false), and the description adds real context on top: per-call token consumption ("호출마다 토큰 1소진"), the fact that repeated calls without an idempotency key are treated as new requests, and a warning not to confuse this key with a provider-specific `idempotency_key`. It does not clarify whether initialization creates any server-side state, which is the main ambiguity for an `init` tool marked read-only.

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 prerequisite is helpfully front-loaded, but the idempotency passage is verbose and partly redundant ("Reuse it ... only to recover that request after a lost response" largely restates "Without it, calling again remains a new request"). A Korean sentence about token consumption sits untranslated at the tail, slightly undercutting scanability.

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 zero-required-parameter init tool with full schema coverage and no output schema, the essentials are present. What is missing is what initialization yields and what the agent should do next, which matters because this is one step in a declaration lifecycle and there is no output schema to reveal the returned handle.

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%, so the baseline would be 3, but the description genuinely carries meaning the schema defers on: `request_idempotency_key`'s schema text is literally "see the tool description," and the description explains its recovery-only semantics and reuse rules. The anonymous-call exclusion for that key is also only stated here.

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?

States a specific verb and resource: "Initialize business establishment declaration," which is unambiguous about what the call does. It does not, however, position itself against the many other `__init` siblings in the namespace (e.g. `workplace__withdrawal__init`, `payroll__amount_change__init`) or explain that it is the first step of a multi-step declaration flow.

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?

Gives one hard prerequisite ("REQUIRES prior fourinsure__session__login call with same account_link_id"), which is genuinely useful gating. But it never says when to choose this tool versus an alternative, nor what the expected follow-up call is after initialization, so the agent must infer the flow from the `init` suffix.

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