Explain one query

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

Adds crucial context beyond annotations: with analyze=true, it actually runs the query and reports measured timings and buffer usage, while remaining read-only and rolled back. This clarifies the real-world impact of the tool and aligns with the readOnlyHint and destructiveHint annotations.

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: purpose, analyze behavior, and usage guidance. No redundant or extraneous 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?

The description covers the primary use case, the behavior of the analyze flag, and safety guarantees. While no output schema exists, it hints at what the report includes (execution plan, timings, buffer usage). Could be slightly richer in detailing return structure or limitations, but it is largely complete for agent selection and invocation.

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 67% (sql lacks a description). The description compensates by explaining that sql is the query to analyze and adding detail to analyze (runs the query, reports timings and buffer usage, still rolled back). Database is already described in 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 description explicitly states the tool explains PostgreSQL execution plans for slow queries, with a specific verb and resource. It also distinguishes itself from sibling tools by pointing users to top_queries for which statement to analyze.

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?

Provides clear when-to-use guidance: apply to a specific statement, and directs users to top_queries as the alternative for discovering which statement to examine. Does not explicitly mention other sibling tools or exclusions, but the context is sufficient.

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