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

Goes well beyond the annotations: it discloses the billing model (20 points per call, charged only on successful retrieval, not on pending or empty results), the exact status/message values for each outcome, and the 24-hour re-query window with per-lookup charging. This explains why readOnlyHint=false and idempotentHint=false without contradicting them.

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 purpose and cost are front-loaded, and each subsequent sentence covers a distinct outcome (pending / approved / empty). Slight redundancy in restating '과금되지 않습니다' for two cases keeps it from a 5, but nothing is wasted.

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 carries the full burden and does so: it enumerates returned fields (PCCC, address, checked_at), status values, and message strings for each branch. An agent can call this and interpret the response without further information.

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% and the schema already says tx_id is the req_pccc transaction ID, so the description largely repeats it. It does add the behavioral meaning of the parameter — that supplying it returns processing status and that results stay queryable for 24 hours — which is useful framing beyond the schema.

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 ('Retrieve a Korean Personal Customs Clearance Code') and identifies the exact input that scopes it (the tx_id from req_pccc). The pairing with req_pccc makes the division of labor between the two siblings unambiguous.

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?

Clearly establishes the precondition that tx_id comes from a prior req_pccc call, and explains that this tool polls processing status. It stops short of an explicit 'call this only after req_pccc returns a tx_id' directive or stating what to do if the tx_id is unknown/expired beyond the 24h note.

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