Get Delivery Estimate

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

The description discloses that the tool returns estimated daily outcomes (reach, impressions, actions) and bid suggestion, which adds value beyond the readOnlyHint annotation. There is 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 short and includes a bullet list for arguments, making it easy to scan. It could be slightly more concise by removing the 'Args:' header, but overall it is clear.

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 simple read-only tool with annotations and a well-defined schema, the description adequately covers what the tool does and what it returns. It does not include output schema, but the return value is described in plain terms.

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 description only restates the adset_id parameter's type and role, which is already implied by its name. The response_format parameter has a description in the schema but is not covered in the tool description, so the description adds minimal meaning beyond what the schema provides.

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 it gets a delivery estimate for an existing ad set. However, it does not explicitly differentiate from the sibling tool meta_get_reach_estimate, which is similar in name and purpose.

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?

No guidance is provided on when to use this tool versus alternatives like meta_get_reach_estimate or meta_get_adset_insights. There are no exclusions or context for use.

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