Bus factor and knowledge silos

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), and the description adds substantive behavioral detail beyond them: the silo thresholds (>= 3 commits and > 80% single-author share) and the precise bus-factor definition (>50% of commits). These thresholds tell the agent exactly how results are computed, not just that the call is safe.

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?

Dense but front-loaded: purpose, then outputs, then the bus-factor definition, then the sibling pointer. Every clause carries information an agent needs to interpret the result, with no filler sentences.

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?

An output schema exists, so return-shape explanation is unnecessary, and the description still supplies definitions of the terms it reports (silo, bus factor). Combined with full schema coverage and annotations, nothing an agent needs to call or interpret this tool correctly 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 description coverage is 100%, so the schema already documents repo_path, top, and include_merges in detail. The description adds algorithmic context but no additional meaning about the parameters themselves, so the baseline of 3 applies.

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 ('Analyze knowledge concentration by commits') and enumerates the concrete outputs: per-directory dominant author and share, silo flags, and the global bus factor. It clearly differentiates from the sibling knowledge_risk by naming it as the tool for line-level ownership.

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 routes the agent to an alternative for a related need ('For line-level ownership and inactive authors use knowledge_risk'), giving a clear condition that selects the sibling. It stops short of a full when-to-use/when-not framing for this tool itself, but the routing is unusually concrete.

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