Add cases to run

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

With no annotations, the description carries the burden of disclosure. It does mention the key side effect that TestExecutions are created, which is useful. However, it omits behavioral details such as idempotency, duplicate handling, required permissions, or error behavior, which limits transparency for a mutating operation.

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 and very concise. The 'TestRun.add_case:' prefix is somewhat redundant with the tool name, but it is not verbose and the core message is front-loaded and 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 tool with only two parameters and no output schema, the description covers the essential purpose and side effect. However, it does not address what happens with invalid or duplicate case IDs, nor the response format, leaving some gaps for an agent to infer.

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%: run_id is described as 'Test run id' and case_ids as 'Comma-separated case ids, e.g. 12,34,56'. The tool description adds no new parameter-specific meaning beyond what the schema provides, so the baseline of 3 applies.

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 uses a specific verb ('add') and resource ('cases to the run'), clearly distinguishing it from run-related siblings like kiwi_run_add_tag or kiwi_run_get_cases. It also explains the underlying effect ('creates TestExecutions'), which further disambiguates from plan-related tools.

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 makes the use case obvious (adding cases to a test run) and the tool name matches the title. However, it does not explicitly state when NOT to use it (e.g., for plans) or name alternatives, though the sibling list implies such distinctions.

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