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

Annotations already declare readOnlyHint=true and destructiveHint=false, but the description adds meaningful context: report names are in Korean, errors reveal DART status 013 and remedies, the return shape is given, and the agent is routed to get_dart_document with rcept_no. It also warns about the 90-day default and pagination. That is far good beyond the thumbnail-protected annotations.

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 description is long but extremely well-structured: purpose first, then exclusions, then args, examples, return shape, error guidance, and a final routing hint. The only slack is that get_dart_major_events is mentioned both in the 'not this tool' list and in the closing sentence, but even that adds the keyword-filtering nuance. Overall it earns its place.

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 6‑parameter tool with a separate search and document tools, the description covers every needed decision: defaults, formats, type codes with Korean labels, example calls, return object shape, pagination, error conditions with remedies, and a pointer to get_dart_document. It leaves no gap that would force the agent to introspect blindly.

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%, but the description adds real meaning: corps such as Korean names, 6-digit codes, or 8-digit DART corporates; it explicitly says omitting the filter gives a market-wide list; it gives each type code (A–J) with Korean labels and the underlying category. The description explains defaults for from/to and pagination limits. This is added value beyond the bare 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?

First sentence uses a specific verb and resource: 'List corporate disclosure filings from DART', with optional filters. It then names alternatives (get_edgar_filings, get_disclosure_feed, get_dart_major_events), which makes it unambiguous which sibling it is not. The purpose is fully disambiguated.

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 description explicitly says 'Not this tool for: ...' and lists three sibling tools with the conditions that select them. It also ends with 'For major events with keyword filtering use get_dart_major_events.' Examples show typical calls. Nothing is left to inference.

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