explain_query

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

Annotations already declare readOnlyHint=true and destructiveHint=false. The description adds a meaningful behavioral constraint by stating 'never ANALYZE,' which rules out statistics updates, but it does not disclose return format, pagination, or other operational details.

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?

The description is a single front-loaded sentence that states the action and the key constraint. It is appropriately terse for a short tool definition, though its brevity leaves important gaps elsewhere.

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?

Output schema exists and annotations cover safety, so return values need not be explained. However, with 0% parameter description coverage and no alternative routing, the definition is only minimally complete for correct 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 description coverage is 0% and the description does not explain the `sql`, `params`, or `database` parameters. Mentioning SQL dialect support does not clarify how any parameter should be supplied.

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 and resource ('Get an estimated query plan') and lists supported database engines. It does not explicitly differentiate from sibling tools such as query_sql or execute_sql, so it remains clear but not fully routing-aware.

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?

Implies the use case (obtain a query plan) and includes a negative constraint ('never ANALYZE'), but it gives no explicit guidance on when to choose this over query_sql, execute_sql, or suggest_sql. Usage is therefore only implied.

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