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

Annotations already cover the safety profile (readOnly, idempotent, openWorld), so the bar is lower. The description adds genuinely useful behavior that annotations cannot convey: zero rows means the source is non-exhaustive rather than truly 'none', the row data is 'as published', a source notice is carried, and the result is explicitly 'not an official result'. These provenance/coverage caveats are exactly the kind of context an agent needs.

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?

Three sentences, front-loaded with the core question and followed by the return shape and the decisive caveats. Every sentence carries weight; the only minor cost is the dense parenthetical clauses, 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?

An output schema exists, so return-value documentation is not required. Given the read-only nature (annotations) and full schema coverage, the description closes the remaining gaps by explaining the non-exhaustive coverage semantics and provenance. It is complete enough to call correctly without overclaiming.

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 100%, so all three parameters are already documented (limit semantics with total/truncated, ministry filter example, corporate_number check-digit validation). The description adds no parameter-level detail beyond this, so the baseline 3 applies.

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 opens with a specific verb+resource: 'Which notifications and certifications ... does gBizINFO publish for this Japanese corporate number?' It names the source (METI), the entity type (corporate number), and the returned fields (ministry, title, date). This is clearly distinguishable from siblings like gbizinfo_company_basic or gbizinfo_resolve_corporate_number.

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 explains what you get and the key semantic caveat (zero rows = unknown, not none), which implicitly guides interpretation. However, it never states when to prefer this tool over siblings such as gbizinfo_company_basic, nor any prerequisites for selecting it. Usage is implied rather than directed.

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