Japanese balance sheet (EDINET)

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

Annotations already declare readOnlyHint and openWorldHint, so the safety profile is covered. The description adds real behavioral context beyond that: figures are in yen, converted via a dated ECB reference rate, sourced from an XBRL filing, and gated on a doc ID. It omits latency, rate limits, or error behavior.

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 opening sentence is front-loaded and load-bearing. The second paragraph is largely persuasive framing ('looking in the wrong market') rather than operational instruction, which spends budget without helping an agent select or invoke the tool.

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 does the work of characterizing the return (line items plus Graham asset tests) and the currency handling, and both parameters are covered. It is complete enough to call correctly, with only minor gaps around return shape detail.

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 documents both parameters, including the ECB rate for `convertTo` and the `edinet_search` source for `docId`. The description largely reinforces rather than extends that, 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 states a specific resource (balance-sheet line items and Graham asset tests for a Japanese filer) and its source (EDINET XBRL filing), so an agent knows exactly what it returns. It clearly distinguishes itself from the sibling `edinet_search`, which supplies the input rather than the figures.

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 gives an explicit prerequisite ('Get a document ID from `edinet_search` first') and frames the use case (Japanese net-nets where the US market is thin). It stops short of stating when NOT to use it or naming what to use for non-Japanese filers, so it is strong but not exhaustive.

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