update_campaign

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

With no annotations provided, the description must carry the behavioral burden. It does disclose important non-obvious behavior: omitted optional fields reset to defaults except where noted, and sending null clears description/start_time/end_time. This is meaningful beyond the schema, though it stops short of covering side effects, permissions, or response behavior.

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 front-loaded. The core action is in the first sentence, and each subsequent sentence adds distinct, valuable behavioral information without repetition or 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 tool with 14 parameters, nested objects, no output schema, and no annotations, the description is too thin. It omits details about what the nested objects accept, what the response contains, and how status interactions with pause/archive/activate siblings should be handled. The behavioral notes are valuable, but they don't make the tool adequately comprehensible.

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 only 14%, so the description needs to compensate. It adds semantics for null-clearing on description/start_time/end_time and the general reset-on-omit rule, but it leaves the meaning of budget, targeting, landing_page_configuration, conversion_event_setting_ids, and several other parameters unexplained. The schema's enums and field names help, but the description itself only marginally compensates for the low coverage.

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 a specific verb and resource: 'Update a campaign by ID.' This distinguishes it clearly from create_campaign and from sibling update tools for other resources (update_ad_group, update_ad), and from status-specific tools like pause_campaign, archive_campaign, and activate_campaign.

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 provides clear context for how to use the tool: it updates an existing campaign and only affects provided fields, with omitted fields resetting to defaults. It doesn't explicitly contrast itself with pause_campaign/archive_campaign/activate_campaign or state when not to use it, but the partial-update framing makes the intended usage reasonably clear.

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