get_last_activity

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

No annotations are provided, so the description carries the full burden. It discloses that the tool returns the most recent activity with summary metrics, but it does not mention whether it can return null/empty, any authentication requirements, or side effects. For a simple zero-param getter, this is minimal but not misleading.

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?

A single sentence with no fluff, front-loading the core function and scope. Every word contributes meaning, making it highly efficient and easy to parse.

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 zero-parameter read tool with an output schema present, the description covers the essential purpose and content. It omits edge cases like missing data or error behavior, but given the simplicity and the schema's availability, it is adequately 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 has zero parameters and 100% coverage, so there is nothing for the description to add. The baseline for zero-parameter tools is 4, and the description does not introduce any parameter-related confusion.

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 resource ('most recent activity') and what it provides ('summary metrics'), distinguishing it from get_recent_activities (plural) by its singular focus. However, it lacks an explicit verb like 'returns' or 'fetches,' and it does not reference sibling tools to aid differentiation.

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?

There is no guidance on when to use this tool versus the many activity-related siblings (e.g., get_recent_activities, get_activity_details). The description implies it is for the latest single activity, but it does not state exclusions or provide routing cues, leaving the agent to infer the appropriate context.

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