update_campaign

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

Annotations already mark this as non-read-only, non-destructive, and idempotent. The description adds meaningful behavior beyond the annotations: only provided fields are updated, status is constrained to ENABLED/PAUSED, target_cpa and target_roas are tied to specific bidding strategies, and dates follow YYYY-MM-DD. No contradiction with annotations.

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?

The description is compact and well-organized: a one-line purpose, one clarifying partial-update rule, then a tidy Args list. Every sentence earns its place, and the most important behavioral note is front-loaded.

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 8 parameters and no schema descriptions, the description covers every parameter, the partial-update behavior, status constraints, bidding-strategy associations, and date formatting. No output schema exists, so return-value detail is not required. The only minor absence is explicit comparison to set_campaign_status, but this is not enough to penalize given the overall completeness.

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 description coverage is 0%, so the description carries the full parameter burden. The Args list documents all 8 parameters with useful details beyond the schema: status values, target strategy context, and date format. This fully compensates for the schema 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 opens with 'Update an existing campaign's properties,' naming the specific verb, resource, and scope. The next sentence clarifies partial-update semantics, which distinguishes it from create/remove campaign and from set_campaign_status.

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?

The phrase 'existing campaign' clearly implies this is for modifying an already-created campaign rather than creating or removing one. However, it does not explicitly mention sibling alternatives like set_campaign_status for status-only changes, so it stops short of full exclusion guidance.

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