Get Co-Change Clusters

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

Annotations already declare readOnly, idempotent, openWorld, and non-destructive, so safety is covered. The description adds valuable behavioral context the annotations cannot: the ≥3-commit threshold, sweep commit exclusion, and the caveat that clusters are correlation evidence, not static dependency. It doesn't mention performance characteristics or result ordering, keeping it below a 5.

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?

Four tight sentences, each earning its place: definition with thresholds, architectural insight, when-to-use call, and relationship to a sibling. Front-loaded with what the tool actually returns.

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?

Given no output schema, the description does well by explaining what clusters represent and their empirical basis, though it doesn't describe the result shape (e.g., cluster membership fields). The parameter and safety burdens are fully covered by schema and annotations, so the remaining gap is minor.

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 single parameter's description already covers multi-project mode and points to list_projects. The description adds no parameter detail, so the schema fully carries the burden; given zero required parameters and complete coverage, this is appropriately high but not exceptional.

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 resource (groups of symbols that historically change together) with the exact algorithmic basis (≥3 shared commits, sweep commits excluded). It goes on to name the sibling it complements (get_blast_radius) and contrasts static vs empirical reach, so the agent can tell it apart.

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 states when to call it: 'when planning a change or splitting work across agents,' plus the consequence of touching one cluster member. It also positions it against the alternative by naming get_blast_radius and contrasting their types of reach.

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