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

Annotations already declare readOnly, idempotent, non-destructive, and closed-world. The description adds genuine value beyond them by clarifying it is a 'read-only text scan, not a guarantee' and therefore best-effort rather than exhaustive — a limitation an agent would otherwise not know.

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 tight sentences, front-loaded with the bug classes and closed with the scope caveat and sibling routing. No sentence is filler.

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 correctly conveys expected findings (blank renders with no error) and sets expectations that results are heuristic, not guaranteed. Nothing needed to invoke it 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 coverage is 100% and there is only one parameter ('code', 'the TSX to check'), so the schema already carries the semantics. The description adds nothing about the input format or size limits, so the baseline 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 ('Scans') and resource ('TSX that uses these components') and enumerates the exact bug classes it detects. It is clearly distinguishable from verify_app, which it explicitly names as the project-wide alternative.

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 frames this as a narrow per-snippet check and routes whole-project validation to verify_app. It stops short of stating explicit exclusions or prerequisites (e.g. what happens if the snippet lacks these components), so it is strong but not fully prescriptive.

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