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

Annotations already declare a safe read, and the description adds substantial context beyond them: ordering, the exclusion rule for pre-existing items, the five-value status taxonomy with what each means, the 14-day skip threshold, and the required posts.read permission. That is exactly the behavioral detail an agent needs before calling.

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?

Three compact sentences, front-loaded with the core behavior, then the status semantics, then the use case and permission. Every clause carries information; nothing is padding.

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 an output schema present, return values need no explanation, and the description covers what matters for interpretation: status meanings, the postId link to get_post, and the auth requirement. Nothing an agent needs to call or interpret this tool 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 id, limit, and workspaceId all documented including defaults and cross-workspace id cautions. The description adds no further parameter detail (e.g., what happens at limit boundaries or pagination), 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?

States a specific verb and resource ('List the items an RSS feed has seen') plus scope details: newest-first ordering and exclusion of items that predate the feed's creation. This clearly separates it from list_rss_feeds (lists feeds) and preview_rss_feed (tests ingestion).

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?

'Use it to answer why an article was or was not posted' gives a concrete selection scenario tied to the status field. It does not explicitly name alternatives such as preview_rss_feed or check_rss_feed, so it stops short of full when-not guidance.

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