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

Annotations declare the mutation profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), but the description adds traits they do not carry: partial-update semantics ('Only the fields given change'), the blast radius ('posts already made from the feed are not touched'), and an authorization prerequisite (autoPublish 'needs the publish scope'). That is exactly the beyond-annotations context this dimension rewards.

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?

A single dense paragraph that leads with the primary effect, then the partial-update guarantee, then the routing advice. The parenthetical '(autoPublish, publish scope; only when the user asked for it)' compresses an auth requirement and a consent rule into four words with no filler.

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 non-destructive, non-idempotent mutation with full schema coverage, no output schema, and no nested objects, the description covers effect scope, partial-update behavior, auth prerequisites, and the alternative workflow. Nothing an agent needs in order 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%, so the baseline is 3; the description nevertheless adds meaning the schema lacks, tying autoPublish to the publish scope and to user consent, and framing accounts/platforms as the interchangeable 'target accounts' lever. It does not add format or syntax detail beyond that, so it stops short of 5.

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?

The description names a specific verb (changes) and two concrete resources (target accounts of an already-followed feed, approval/publish behavior), and explicitly positions itself against the unfollow/refollow path. An agent can distinguish it from follow_feed, unfollow_feed, and update_post without opening any schema.

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?

It names the alternative workflow explicitly ('Use it instead of unfollowing and following again, which would skip the articles already listed in the feed') and gives the condition that selects it. It also scopes autoPublish with a consent rule ('only when the user asked for it'), which is a when-to-use constraint, not just a field note.

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