sql_check_nulls

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

No annotations are provided, so the description carries full behavioral burden. It implies a read-only SELECT query (finding rows), which suggests non-destructive behavior. However, it doesn't disclose whether it returns all matching rows, respects any limit, which table context it uses, or the result shape. The non-destructive nature is implied but not explicit, and there's no detail on return size or pagination.

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?

Two sentences, no filler. The first sentence states the action clearly, and the second adds a practical rationale. Every sentence earns its place, though a reader-facing detail like column format or return limit is absent.

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 tool is a query-like operation (SELECT with IS NULL) with two fully-documented parameters and no output schema defined. For a simple data-lookup tool, the description plus schema cover the essentials adequately. However, since there's no output schema, the description could clarify what gets returned (matched row IDs, full rows, counts), and it doesn't address potential large result sets that an agent should anticipate.

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%, so the schema documents both parameters ($table, $columns) fully. The description adds the intent ('find rows with NULL values') that ties the parameters together, but doesn't add syntax or format details beyond what the schema provides. Baseline 3 is appropriate when the schema carries the parameter documentation burden.

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 states a clear verb+resource: 'Find rows with NULL values in specified columns.' It also adds the purpose ('finding missing/incomplete data that might be causing bugs'). While it doesn't explicitly distinguish from siblings, the verb phrase is specific enough to differentiate from sql_run_query, sql_count_and_sample, etc., most of which have broader or different intents.

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 usage ('useful for finding missing/incomplete data that might be causing bugs') by giving a diagnostic intent. However, it provides no explicit comparison to alternatives like sql_find_data or sql_run_query, nor any when-not-to-use guidance. The use case is stated but no exclusions or alternative selections are given.

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