get_campaign_forecast

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

With no annotations, the description carries the full burden. It discloses meaningful behavioral traits beyond the schema: the forecast uses 'current or overridden budget' and explicitly calls out the LIFETIME_BUDGET limitation. While it doesn't discuss auth or side effects, 'get' implies a safe read operation, and the disclosed constraints add significant value.

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 three sentences with no redundant content. It front-loads the purpose and efficiently adds the budget basis and the key limitation, every sentence earning its place.

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 get-forecast tool with no output schema, the description explains the return value ('Returns the forecast'), the basis (current or overridden budget), and a critical limitation (LIFETIME_BUDGET unsupported). It lacks explicit guidance on how to pass an overridden budget via the body parameter, but the body parameter description references get_endpoint_definition, partially filling that gap. Overall, it is reasonably complete.

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?

The input schema already describes all 5 parameters with 100% coverage, so the baseline is 3. The description adds budget-related context but does not map that to specific parameters (e.g., how to set an overridden budget in the body). The schema's descriptions of body and campaign_id already provide necessary parameter 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?

The description clearly states the tool's function with a specific verb and resource: 'Get forecast for a campaign.' It distinguishes itself from sibling tools like get_spa_campaign_by_id by focusing on forecasting rather than campaign details, and the LIFETIME_BUDGET note further clarifies scope.

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 description provides clear context for when to use the tool (to obtain a forecast) and explicitly states a key exclusion: forecasting is not supported for LIFETIME_BUDGET campaigns. It does not name alternative tools, but no sibling tool offers forecasting, so the guidance is sufficient.

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