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

Annotations already declare readOnlyHint=true, idempotentHint=true, and openWorldHint=false, so safety and determinism are covered. The description adds real value by disclosing the return composition (library posts + recent posts grouped by status), but says nothing about pagination, result caps, or whether missing campaign_ids error versus return empty. With annotations carrying the safety profile, a 3 is appropriate.

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 tight sentence with the subject front-loaded and the status enumeration providing useful scanning detail. The phrasing "its library posts and its recent posts" is slightly compressed and leaves the distinction between the two groups unexplained.

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?

No output schema exists, so the description bears the burden of describing the response — it does so at a high level (library posts, recent posts by status) but omits volume limits, pagination, and failure behavior for a bad id. Adequate to call the tool, not complete enough to predict its output.

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?

One parameter (campaign_id) with 0% schema description coverage; the schema only supplies type=string and format=uuid. The description mentions the campaign concept but never explains that the id must be obtained from list_post_campaigns or what happens with an unknown id, so it does not fully compensate for the coverage gap.

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 the resource precisely — a single recurring/evergreen post campaign — and enumerates what comes back: its library posts plus recent posts bucketed as scheduled, published, flagged, or failed. The word "One" implicitly contrasts with the sibling list_post_campaigns, though it never names that sibling explicitly.

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: an agent can infer this is the detail-fetch for a single campaign (as opposed to list_post_campaigns for enumeration), but there is no explicit when-to-use, no prerequisite statement, and no named alternative. Nothing is misleading, but nothing guides selection either.

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