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 the 'estimated or actual' execution plan mode, which is useful, but it does not mention that analyze=true will actually execute the query or any other side effects beyond safety. This is a minor addition over what annotations and the schema already convey.

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, focused sentence without redundant words. It front-loads the verb and resource and is appropriately sized for the tool's simplicity at a high level.

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 rich schema (100% coverage), clear annotations, and presence of an output schema, the description suffices to orient an agent toward the tool's core purpose. It does not summarize advanced parameters like parameter binding or raw XML, but these are fully documented in the schema, so the description does not need to carry that burden.

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 100%—every parameter has a detailed description. The main description does not add parameter-specific meaning beyond the 'read-only' qualifier, so the baseline of 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?

The description uses a specific verb ('Generate') and resource ('execution plan') with a clear scope ('for a read-only SQL query'). It distinguishes the tool from siblings like execute_sql (which executes queries) and plan cache tools that retrieve existing plans.

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 use for read-only queries and plan analysis, but it does not explicitly state when to use this tool vs alternatives such as execute_sql or get_plan_cache_analysis. There are no exclusions or alternative tool references, only the 'read-only' qualifier as a soft usage signal.

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