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

Annotations already declare readOnlyHint, idempotentHint, non-destructive and non-openWorld, so the safety profile is fully covered. The description adds the useful fact that the payload is the full page text in Markdown, but says nothing about error behavior for a bad id/url, missing pages, or language fallback.

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?

Very short and front-loaded: return format first, then identifier guidance. The bilingual duplication ('/ Полный текст услуги') is redundant for an agent reading English, but the whole description is still only two sentences.

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 simple read tool with no output schema and full schema coverage, the description is mostly sufficient, and it does state the Markdown return format. However, with required parameters = 0 it never clarifies that at least one of id/slug/url must be supplied, nor what happens if none is given — a real gap for correct invocation.

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 id, url, slug and lang are already documented in detail (including the lang enum and the 'from a list result' provenance). The description adds only the OR-relationship between id, slug and url, and omits lang entirely; baseline 3 is correct when the schema does the heavy lifting.

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: retrieving the full text of one service page, plus the return format (Markdown). This is clearly distinguishable from list_services and get_blog_post. It stops short of explicitly naming a sibling, so a 5 is not warranted.

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?

The description says which identifiers to pass but never states when to use get_service rather than list_services or search_content. There are no exclusions, prerequisites, or alternative-tool routing, so the agent must infer usage entirely from the name.

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