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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the description only needs to add expansion semantics. It does that by explaining that include pulls the routing tree with flows, rules and destinations, plus pixels, postbacks and creatives. It does not describe the base campaign fields returned when include is omitted.

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 short sentences with the core resource lookup front-loaded and the optional expansion second. Nothing is wasted and there is 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?

With no output schema, the description carries the burden of describing return content, and it does so for the include-expanded parts. It falls short only in not characterizing what the base campaign object contains when include is omitted.

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 a baseline of 3 applies, but the description earns a point by explaining that include expands the response into a routing tree with rules and destinations rather than just returning raw ids. That adds meaning beyond the schema's bare comma-separated list.

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: fetch one campaign by numeric id. This clearly separates it from list_campaigns and from get_campaign_preflight, though the description never names those siblings 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 by 'one campaign by numeric id' and the include option. There is no guidance on when to prefer this over list_campaigns, get_campaign_preflight, or get_campaign_blacklist, and no stated prerequisites.

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