get_daily_spend

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

The annotations already declare readOnlyHint=true, indicating this is a safe read operation. The description adds some context by specifying 'across all connected ad accounts', which implies it aggregates data, but it doesn't disclose additional behavioral traits like rate limits, authentication needs, or data freshness. With annotations covering safety, the description adds minimal value beyond that.

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 a single, efficient sentence that front-loads the core purpose without unnecessary words. Every part of the sentence earns its place by specifying the action, resource, and scope, making it highly concise and well-structured.

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?

Given the tool's complexity is low (a read operation with two optional parameters), annotations provide safety context, and schema coverage is high, the description is adequate but has gaps. It doesn't explain the output format or any limitations, and with no output schema, this leaves the agent uncertain about return values. It meets minimum viability but lacks completeness for optimal agent use.

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 has 100% description coverage, fully documenting both parameters with details like default values and enum options. The description doesn't add any meaning beyond what the schema provides, such as explaining how 'days' interacts with 'platform' or the format of the breakdown. Baseline 3 is appropriate when the schema does the heavy lifting.

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 verb 'Get' and the resource 'daily spend breakdown across all connected ad accounts', which specifies what the tool does. However, it doesn't explicitly differentiate from sibling tools like 'get_performance' or 'list_campaigns', which might also involve retrieving ad-related data, so it misses full sibling distinction.

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 no guidance on when to use this tool versus alternatives, such as 'get_performance' or other sibling tools. It lacks explicit context, exclusions, or prerequisites, leaving the agent to infer usage based on the tool name alone.

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