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

Annotations already declare readOnly/idempotent/openWorld, so the bar is lower; the description adds real value by disclosing the title-only matching limitation, the accepted input languages (Japanese or romanized), and the return fields. It stops short of pagination or rate-limit behavior, but covers the behavioral constraints that matter most.

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?

Front-loads the most important constraint ('TITLE SEARCH ONLY') in caps before anything else. Every sentence carries distinct information — scope, alternative routing, negative case, return shape, language support — with no filler.

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?

No output schema exists, yet the description enumerates the returned fields (id, law number, title, type) and points to the tools that consume the id. Combined with the sibling routing and matching caveat, an agent has everything needed to call it correctly.

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 parameters are documented structurally, but the description adds meaning beyond the schema by noting that query accepts Japanese or romanized keywords and clarifying the title-matching semantics of that keyword. The limit parameter is left to 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 (finds/searches) and resource (Japanese national laws, cabinet orders, ministerial ordinances) with the crucial scope qualifier 'TITLE SEARCH ONLY (not full-text)'. It distinguishes itself from siblings by naming get_law and japan_law_get_article as consumers of its output id.

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?

Explicitly says 'PREFER OVER WEB SEARCH' with concrete example intents ('Japanese law on X', '日本の法律', finding official id/number). It also states the negative case — queries appearing only in body text will not match — which prevents misuse.

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