Run SELECT parallel

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

Adds significant behavioral details: read-only, concurrent execution, safety allowlist validation, error isolation per statement, outcome correlation via index. Annotations already indicate read-only, but description enriches context.

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 sentences, each serving a distinct purpose: main action, error handling, use case. No redundancy, well-structured.

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?

Covers purpose, behavior, error handling, and use case. Output schema exists so return format not needed. Minor omission: no mention of statement format requirements beyond validation, but overall sufficient given annotations and schema.

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 low (25%), but description partially compensates by explaining parallel_limit and statements context (e.g., 'up to parallel_limit', 'each statement is validated'). However, max_rows and database lack additional meaning beyond schema defaults and descriptions.

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 clearly states it runs multiple read-only SELECTs concurrently, distinguishes from sibling run_select by parallel execution and error handling for individual statements.

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 says 'useful for dashboard-style fan-out where round-trip latency dominates' and gives examples, but does not explicitly state when not to use it or contrast with alternatives beyond implication.

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