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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world, so the safety profile is covered. The description adds useful context beyond that by describing the returned payload and the ordering constraint against mutations. It omits failure behavior, e.g. what happens when the id or name does not resolve.

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, both load-bearing: the first front-loads the return shape, the second delivers the usage constraint. No repetition of the title or annotations.

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 carries the burden of explaining return values and does so by naming the per-post fields. It does not mention campaign-level metadata (name, status, dates) or pagination/size limits for large campaigns, which leaves a small gap for a read tool.

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% and the schema already documents that the id accepts either an id or a name. The description adds no parameter-level detail beyond that, so the baseline 3 applies — the schema carries the semantics.

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 (read) and resource (one campaign) and enumerates exactly what comes back: planned posts with date, kind, theme, angle, and written status. 'One campaign in full' implicitly contrasts with the sibling list_campaigns, so an agent can distinguish the single-record read from the list read.

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?

'Read it before changing anything about the campaign' gives an explicit read-before-mutate precondition, which is genuinely actionable guidance. It does not name alternative tools (list_campaigns, get_post) or state when not to use it, so it stops short of full routing guidance.

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