mailchimp_reports_get_open_details

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

With no annotations, the description must disclose behavioral traits, but it only states the basic action. It does not mention pagination behavior (though parameters imply it), response format, authentication requirements, rate limits, or what 'detailed' means in terms of data scope. This is a significant gap for a read operation with no annotation safety net.

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 sentence with no wasted words, making it easy to parse. While it is brief, it is not under-specified to the point of being a tautology; it communicates the core action effectively, though 'detailed' is somewhat vague.

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?

The tool has 4 parameters, no output schema, and no annotations, yet the description provides only a minimal phrase. It offers no context about the report's structure, how to interpret results, or how it relates to other report tools. The lack of detail leaves the agent with insufficient information to fully understand the tool's behavior and output.

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 100%, so all parameters (count, since, offset, campaign_id) are already described in the schema. The tool description adds no extra semantic meaning beyond 'open information', so the baseline of 3 is appropriate—schema does the heavy lifting without needing further elaboration.

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 'Get detailed open information for a campaign' uses a specific verb ('get') and resource ('open information') tied to a campaign. It clearly indicates the tool's function, and the resource type ('open') distinguishes it from sibling tools like click details, though it doesn't explicitly differentiate itself.

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 such as mailchimp_reports_get_click_details or mailchimp_reports_get_email_activity. There is no mention of context, prerequisites, or exclusions, leaving the agent to infer usage solely from the name.

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