coupling

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

Annotations already mark the tool as read-only and idempotent, and the description goes beyond this by explaining the behavioral basis: the tool relies on commit co-occurrence rather than static import statements. This adds meaningful context about how the analysis works.

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 compact and front-loaded: the first sentence explains the core concept, and the second gives the practical use case. It is economical, though the phrase 'dependencies no import statement reveals' is slightly awkward and could be clearer.

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 read-only tool with three optional, fully documented parameters and no output schema, the description provides enough context for an agent to understand what it does, when to use it, and what kind of results to expect (file pairs). It does not detail the output format, but the concept is straightforward.

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 schema fully documents repo, min_support, and min_confidence. The description does not add parameter-specific guidance, but the baseline of 3 is appropriate since the schema carries the load.

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 core function: identifying file pairs that frequently co-occur in the same commits, revealing implicit dependencies not visible via imports. It is clear enough to distinguish it from a generic 'list files' tool, though it does not explicitly name sibling alternatives.

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 provides a concrete usage context: 'Use it to learn what else an edit usually drags along before touching a file.' This tells an agent when to invoke it, though it does not mention when not to use it or point to alternative tools.

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