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

Annotations only tell the agent this is a non-destructive, non-idempotent write; the description goes well beyond that by disclosing inheritance of suite + environment, that each eligible case is seeded BLOCKED, the soft-error condition, and the return payload. These are exactly the behaviors an agent needs before invoking an irreversible create.

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?

Three dense sentences, zero filler, front-loaded with the create action and scope before the inheritance, seeding, and error details. Every clause carries information an agent would otherwise have to guess.

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?

No output schema exists, and the description supplies the return shape (new run id + retried count) as well as the failure mode. For a single-parameter create tool, nothing an agent needs to call it correctly is missing.

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 coverage is 100% and only one parameter exists, so the baseline is 3; the description adds real meaning by explaining that testRunId becomes the parentRunId linking the run chain and drives inheritance of suite and environment, which the schema's "UUID of the parent test run" does not convey.

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?

Specific verb+resource with scope: "Create a child test run seeded with the failed + blocked cases of a parent run." It clearly distinguishes itself from the sibling create_test_run, which creates an unseeded run, by naming the seeded subset and the parent-child link.

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 name and first sentence make the use case (retrying failures from an existing run) obvious, and it gives an explicit when-not: "Soft-errors when the parent had no failing or blocked cases." It stops short of naming create_test_run as the alternative for a fresh unrelated run, so not a 5.

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