explain_query

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

No annotations are provided, so the description must fully disclose behavior. The word 'guarded' hints at restrictions, but it does not explain whether the operation is read-only, what happens on disallowed queries, or any side effects. More detail is needed for a tool with zero annotation coverage.

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, well-structured sentence of 8 words that immediately conveys the core purpose. Every word is necessary and the key information is front-loaded.

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?

Given the tool's simplicity (1 parameter, no output schema, no annotations), the description covers the basic purpose and constraint. However, it lacks details on output format, error handling, and how to specify the table name within the query. A slightly more complete description would improve usability.

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% for the single parameter, which describes the query string as 'EXPLAIN SELECT query.' The description adds the context of 'guarded' and 'allowed tables', which provides additional semantic meaning beyond 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 clearly states the action ('run'), the specific query type ('EXPLAIN SELECT'), and the scope ('against allowed tables'), which distinguishes it from sibling tools like run_readonly_query that run general read-only queries.

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?

The description implies that this tool should be used specifically for EXPLAIN SELECT queries on permitted tables, and not for other query types or tables. It does not explicitly mention when to avoid or provide alternatives, but the context is clear.

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