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

Annotations already declare read-only, idempotent, closed-world behavior, so the bar is lower. The description adds genuinely useful operational context beyond that: the feed is polled every few minutes and page 1 is refreshed immediately when a new post appears, which tells an agent the data is near-real-time and that results can shift between paginated calls.

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?

Front-loaded with the purpose in the first clause before the field enumeration. The inline field list is dense but pays for itself by describing the return shape in a tool with no output schema; there is little wasted wording.

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 no output schema, the description covers purpose, source, ordering, freshness cadence, and enumerates all returned fields including the `has_blog_post`/`url` interaction. Nothing an agent needs to call it correctly is missing.

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% with both `page` and `per_page` documented (defaults, min/max) in the schema itself. The description adds no parameter-level meaning such as how ordering interacts with paging, so the 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?

Specific verb+resource: every post from rust.facepunch.com/news, newest first, with an explicit scope statement. No sibling tool covers this feed, and the description makes that unambiguous by naming the source domain and content domain (updates/devblogs).

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 rather than stated — an agent can infer this is the tool for Rust news/devblogs, but the description gives no explicit when/when-not cues or pointers to alternatives (e.g., get_data_freshness for cache state). With no closely overlapping siblings, the risk is low, but guidance is absent.

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