get_diff_stats

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

No annotations are provided, so the description must disclose behavioral traits. It states the tool retrieves stats from the 'latest VRT run,' implying a dependency on a recent run, but does not mention whether it is read-only, requires authentication, or any side effects.

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, concise but lacking detail. It omits essential information about parameters and output, so it is not optimally structured for comprehensive guidance.

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?

With no output schema, no parameter descriptions, and no annotations, the tool description fails to provide sufficient context. An agent cannot determine what the returned stats look like, how to construct a request, or any constraints (e.g., valid values for parameters).

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?

Input schema has four parameters (project, environment, scenarioLabel, viewport) with 0% schema description coverage. The description does not explain any parameter meaning, format, or usage, leaving the agent with no help beyond the parameter names.

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 returns 'detailed diff stats for one scenario from the latest VRT run,' identifying the specific resource (diff stats), scope (one scenario), and context (latest VRT run). However, it does not differentiate from siblings like 'get_scenario_details' that might also provide scenario information.

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 on when to use this tool versus alternatives such as 'get_scenario_details' or 'get_run_failures.' There is no mention of prerequisites (e.g., a VRT run must exist) or any exclusions.

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