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

Annotations already declare readOnly, idempotent, and non-destructive behavior, so safety is covered. The description adds that results carry a summary preview and that count_only collapses the response to a count, but says nothing about pagination via the before_id/before_published_at cursors or result ordering defaults.

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 sentences, front-loaded with the primary behavior; the compact view list is efficient. Slightly list-heavy but no wasted filler for a 13-parameter tool.

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 usefully names the returned fields, which covers the gap. However, for a 13-parameter list tool it omits pagination behavior and sorting defaults, leaving an agent to guess how to page through results.

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%, so every parameter is already documented, including count_only's semantics and the required feed_id/tag_id/folder_id conditionals. The description's view enumeration and count_only note largely restate the schema rather than adding new meaning.

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 ('List articles') and names the fields returned (title, source, date, summary preview), which is more than a restatement of the title. It does not distinguish itself from closely related siblings like get_saved, get_recently_read, or get_article, whose scopes overlap with the listed views.

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 enumerated views ('newsfeed, by-feed, by-folder, by-tag, tagged, highlighted, noted') imply the available scopes, but the description never says when to prefer this tool over get_saved, get_recently_read, or get_article. Usage must be inferred from the view list rather than stated.

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