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

No annotations are provided, so the description carries the behavioral burden. It discloses the outcome (returns public URL), the exclusivity constraint, and the binary-asset fallback. It does not mention idempotency, whether an existing subdomain is treated as an error (only in schema), or authentication expectations, leaving some behavior implicit.

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?

Four short sentences, front-loaded with purpose and return value; each sentence adds a constraint or routing hint without redundancy.

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 tool with 5 optional parameters and no output schema, the description covers purpose, source selection, optional subdomain/PIN, and return value. It leaves error semantics (subdomain_taken) to the schema, which is acceptable, but a brief note on response shape beyond 'URL' would be more complete.

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 already documents all five parameters (coverage 100%), so the baseline is 3. The description adds the mutual-exclusion rule across html_content/pdf_base64/files and clarifies that files are for text-only static sites, which is decision-relevant beyond the schema fields.

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 and resource: 'Публикует сайт на htmlkin.ru' and states the return value (public URL). Listing the three accepted source formats (html_content, pdf_base64, files) further defines the operation and distinguishes it from sibling delete/get/update tools.

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 explicitly says 'Принимает ровно один источник' (exactly one source), guiding parameter selection, and routes binary assets to ZIP via REST API or browser, an explicit alternative. It does not, however, contrast with htmlkin_update/delete, so sibling differentiation is incomplete.

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