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

Annotations already declare readOnly, idempotent, openWorld and non-destructive, so the safety profile is covered. The description adds genuinely useful return-content context that annotations cannot convey: unlisted companies are included, and the response carries the IsraBase page URL and nesach order URL.

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 key fact (what record, keyed by what) is front-loaded and the whole thing is short. The Hebrew sentence duplicates the English content, but it plausibly serves Hebrew-query matching, so the redundancy is defensible rather than wasteful.

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 must hint at returns, and it does: unlisted-company coverage plus the two URLs. It is slightly thin on what other fields the record contains (status, directors, etc.), but nothing needed to invoke the tool correctly is missing.

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% – the single parameter is fully documented with a 9-digit pattern and integer range. The description only adds the Hebrew term ח.פ as an alias, which is mild value beyond the schema; baseline 3 is appropriate.

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 the full registry record for one Israeli company, keyed by its 9-digit ח.פ. The 'one company by number' framing implicitly separates it from search_companies, though no sibling is named explicitly.

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?

Usage is only implied: an agent infers it should call this when it already holds a company number and wants the detail record. There is no explicit when-not (e.g., 'use search_companies if you only have a name') and no prerequisites stated.

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