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

With no annotations, the description carries the full burden and does it well: it discloses the authorization requirement (administrative preview token), the safe read-only nature ("Never publishes or changes state"), the important side-effect caveat that inactive articles stay hidden publicly until the original author publishes them, and the exact return content. It even clarifies this is preview context, not a live public webpage, which preempts a plausible misinterpretation.

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?

Dense but front-loaded – the core action and its scope come first, followed by return contents, then caveats. Every sentence adds information (auth, return fields, hiding behavior, no-state-change), with only mild redundancy between "Context only, not a public webpage" and "Never publishes or changes state."

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 and no annotations, the description usefully enumerates the return payload (shared version, draft_revision, localized title/description/canonical URL, article titles/URLs/flags), which is exactly what an agent needs. The remaining gap is the undefined `slug` parameter and any error/authorization-failure behavior.

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 0% across three required parameters with no titles or descriptions, so the description must compensate. It partially does: "in ru or en" effectively constrains `language`, and "administrative preview authorization" explains what `token` is for. However `slug` is never defined (no format, no indication of which section is identified), so a third of the parameters remain opaque.

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 ("Preview one privately saved materials section") plus the supported languages (ru/en), so the action is unambiguous. It functionally separates itself from the save/publish siblings by declaring it never publishes or changes state, though it never names an alternative tool explicitly, which keeps it just short of a 5.

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: the word "privately saved" and "administrative preview authorization" signal this is for inspecting a draft section rather than reading public content. There is no explicit when-to-use statement, no when-not-to-use, and no pointer to the sibling tools (save/publish/get) that would be the alternatives, leaving the agent to infer the routing.

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