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

Annotations already declare readOnlyHint=true, openWorldHint=true and destructiveHint=false, so the safety profile is covered. The description adds only the scope of the result set (INN list per date) and adds nothing about result size, limits or freshness — adequate but thin.

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?

Two short sentences, front-loaded with what is returned and then the optional filter — no wasted words.

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 two-parameter read-only list tool with full schema coverage and no output schema, the description is minimally sufficient, but it omits any indication of return volume, pagination or how INNs are ordered — relevant because a full-day EGRUL extract can be very large.

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%: both `date` (yyyy-mm-dd) and `region` (2-digit code, КПП/ОГРНИП semantics, all regions when omitted) are fully documented in the schema. The description only echoes the region filter, so 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?

States a specific verb+resource: the list of INN of organizations registered in EGRUL on a given date, plus an optional region filter. An agent can distinguish it from sibling check_* tools and from new_entrepreneurs/updated_organizations, though those siblings are never named.

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 implied by the phrasing ('registered on the specified date', 'can be filtered by region'), which conveys context but no when/when-not guidance and no explicit routing to siblings like updated_organizations or search_organizations.

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