Files that change together

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds valuable behavioral context beyond that: it reads git log once per call rather than the scored run, an empty list means no pair cleared thresholds, and both thresholds must be cleared. No contradiction with annotations.

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?

Every sentence earns its place: purpose, use case, sibling distinction, performance behavior, empty-result semantics, and threshold semantics. 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?

For a read-only list tool with an output schema, annotations, and only three optional parameters, the description fully covers when to call it, what it returns at a high level, how to interpret empty results, cost implications, and parameter meanings. Nothing material 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 the description goes further by explaining what each parameter means operationally: min_support 5 requires five shared commits, min_confidence 0.5 means the rarer file moved with its partner half the time, and repo defaults to the server's own root. This helps the agent choose thresholds appropriately rather than treating them as opaque numbers.

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?

States a specific verb and resource: 'Lists file pairs that keep landing in the same commits over the churn window, strongest first, at most 50.' It also differentiates from list_duplicate_functions, so an agent can distinguish this tool from its sibling immediately.

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?

Explicitly tells when to use it: 'Use it before editing a file to learn what an edit drags along.' It also gives a clear alternative and exclusion: 'Use list_duplicate_functions for copied code rather than co-change.'

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