blast_radius

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

Annotations already declare readOnlyHint: true and openWorldHint: false, so the safety profile is known. The description adds the output specifics (fan-in/fan-out/routes/entities) and a workflow hint, but does not disclose additional behavioral traits like cost, side effects, or data sources. With annotations covering the main safety aspect, this is adequate but not rich.

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?

Two sentences, no redundancy. The first sentence front-loads the function, the second gives a crisp usage directive. Every word earns its place.

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?

The tool has one parameter, no output schema, and readable annotations. The description explains what the tool reports (fan-in, fan-out, routes/entities) and when to call it, which is sufficient for a simple read-only analysis command. It could be more explicit about output format, but the overview is adequate.

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?

The schema already provides 100% coverage for the single 'path' parameter with a clear description ('file path or module, relative to repo root'). The description reinforces this by saying 'Given a file or top-level module path' but adds no new semantic detail beyond the schema. Baseline 3 applies due to high schema coverage.

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?

Description states exactly what the tool does: given a path, it reports fan-in, fan-out, and routes/entities. This is a specific verb ('report') with clear resource ('file or top-level module path') and outputs, making it easily distinguishable from sibling analysis tools like xray_scan or arch_summary.

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 clear context: 'Call BEFORE editing anything load-bearing.' This tells the agent when to invoke the tool but does not explicitly name alternatives or state when not to use it. It lacks the 'when-not/alternatives' clarity of a 5.

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