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

Beyond the annotations it adds real behavior: per-call token cost ('호출마다 토큰 1소진'), that a XBOSS job is created and its result persisted, and the explicit warning that '이 호출은 순수 읽기 전용이 아닙니다' — consistent with readOnlyHint=false rather than contradicting it. It also clarifies that the optional key does not apply to anonymous calls and must not be confused with a provider-specific idempotency_key. Return format and pagination are unaddressed, but no output schema exists so the burden is lighter.

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?

Useful content is front-loaded and ordered well (prerequisite, purpose, idempotency, cost/behavior), but the idempotency discussion runs several sentences for an optional key and includes the confusing, likely mistranslated 'anonymous taste calls' line that does not earn its place. The Korean cost/XBOSS sentences are substantive but read as generic boilerplate appended after the core purpose.

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, free-form-payload validation tool, the description covers the essentials an agent needs: auth precondition, cost, that it is not a pure read, and that nothing is submitted. The payload contract (missing_required_fields / field_errors) is carried by the input schema rather than the description, which is acceptable, though the schema note 'Nothing is saved or submitted' sits in mild tension with '결과를 저장합니다' and would benefit from one clarifying clause.

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 baseline would be 3. The description earns above baseline by explaining what request_idempotency_key means operationally (recovery-only key, distinct from the provider's own idempotency_key, unavailable to anonymous calls), adding semantics the schema's one-line description does not carry. It says nothing about account_link_id, though the schema already documents that fully.

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 gives a specific verb and resource: 'Validate business establishment declaration draft without submission.' The 'without submission' clause clearly distinguishes it from a submit step, and 'draft' scopes it to pre-submission validation. It does not, however, name the sibling init tool it must follow (that context lives in the input schema's description, not the tool description).

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?

It states an explicit prerequisite ('REQUIRES prior fourinsure__session__login call with same account_link_id') and unambiguous idempotency-key reuse guidance (reuse to recover a lost response; new key for new execution). It does not explicitly say which sibling to call first or which to call after validation succeeds, so cross-tool routing is left to the schema description.

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