Change Hotspots

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

With readOnlyHint=true already covering safety, the description adds meaningful behavioral insight: the correlation with defect density and the requirement for repo_path when the server isn't started in a git repo. This goes beyond annotation-provided information and helps the agent anticipate when the tool may fail or need additional input.

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 three sentences: the first states the purpose, the second provides valuable context, and the third gives a critical usage note. Every sentence earns its place with no fluff, and the front-loaded structure ensures the core function is immediately 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?

Even without an output schema, the description covers what the tool does, why it matters (defect correlation), what actions to take based on results, and a key prerequisite (repo_path). For a read-only analysis tool with four optional parameters documented in the schema, this is complete enough for an agent to select and invoke it effectively.

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%, so the baseline is 3. The description does not add extra parameter semantics beyond the schema; it only reiterates the repo_path note already present in the schema. Therefore, no additional value is provided beyond the schema, resulting in a baseline score.

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 opens with a specific verb and resource: 'Find files that change most frequently,' which unambiguously defines the tool's purpose. The title 'Change Hotspots' reinforces this, and the additional context about defect density distinguishes it from generic change analysis tools like 'churn' by clarifying the analytical focus.

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 gives clear use cases ('identify files that need refactoring, better test coverage, or architectural attention') and a critical prerequisite (repo_path when not in a git repo). However, it does not explicitly contrast with sibling tools like 'churn' or 'complexity_trend', nor state when not to use this tool, so it falls short of a 5.

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