blast_radius

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

Annotations already cover read-only, idempotent, non-destructive, closed-world behavior, so the description only needs to add what they cannot. It does: it discloses that matching is textual rather than semantic and that same-name symbols are included, warning the agent about false positives — a genuinely useful caveat beyond structured fields.

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?

Three short sentences, front-loaded with the core purpose, then the kind hint, then the sibling routing. No filler and no repetition of schema content.

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?

With no output schema, the description partially compensates by mentioning counts by kind and totals behavior. It leaves the summary-vs-detailed output shape to the schema, which is acceptable, but a mutation-free read tool with 5 params could say slightly more about result structure.

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%, so the baseline is 3, but the description adds real semantics: it explains what kind:call actually selects (call-containing lines) and that totals aggregate across all kinds. Mode, root, and file_context meaning come entirely from the schema.

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 first sentence states a specific verb and resource ('find textual usage candidates with counts by kind'), which disambiguates the metaphorical tool name. It explicitly distinguishes itself from exact_references. It does not, however, differentiate from the grep/search siblings, which do similar textual lookups.

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?

It names an alternative (exact_references) with the exact condition that selects it — binding-resolved TS/JS rename checks — and gives a concrete usage hint ('use kind:call for call-containing lines'). No guidance on when this tool is the wrong choice versus grep/search, so not a 5.

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