get_test_impact

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

No annotations are provided, so the description must carry the behavioral burden. It discloses the traversal mechanism, the hop limit, and the return format. It implies a read-only operation consistent with the 'get' prefix, though it does not cover edge cases or prerequisites.

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 concise: three sentences covering purpose, method, and output. There is no redundant or filler content, and the most important information is front-loaded.

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 return structure is documented, which compensates for the missing output schema. However, with no annotations and no parameter explanations, the agent cannot confidently construct a correct invocation, especially for the optional base and head parameters. The description is sufficient for understanding the tool's purpose but not for reliable parameter usage.

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 0%, and the description provides no meaning for the repo, base, or head parameters. The term 'changed files' hints at a diff, but the role of base and head is not explained, leaving the agent to guess how to specify the change.

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's function as selecting existing tests for a change, and adds algorithmic detail about walking the reverse-import graph up to 2 hops. However, it does not differentiate itself from sibling tools such as get_blast_radius or find_suspects, which would elevate it to a 5.

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 phrase 'for this change' gives clear context for when the tool should be used. It does not mention explicit alternatives or exclusions, but the intended scenario is reasonably apparent from the opening question.

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